From 79a678f1625937212a4e0819c58326f2390f5057 Mon Sep 17 00:00:00 2001
From: asrael <asrael@pxl8.org>
Date: Sun, 9 Nov 2025 06:30:17 -0600
Subject: [PATCH] wip procgen

---
 demo/main.fnl         | 131 ++++++------
 demo/mod/worldgen.fnl | 151 ++++++++++++++
 src/lua/pxl8.lua      |  17 ++
 src/pxl8.c            |  11 +
 src/pxl8_bsp.c        | 126 ++++++++++-
 src/pxl8_bsp.h        |   9 +-
 src/pxl8_game.h       |   4 +
 src/pxl8_gfx.c        | 300 ++++++++++++++++++++++-----
 src/pxl8_gfx.h        |   1 +
 src/pxl8_io.c         |   1 +
 src/pxl8_math.c       |  67 ++++++
 src/pxl8_math.h       |  12 ++
 src/pxl8_procgen.c    | 472 ++++++++++++++++++++++++++++++++++++++++++
 src/pxl8_procgen.h    |  56 +++++
 src/pxl8_script.c     |  20 +-
 src/pxl8_sdl3.c       |   2 +
 src/pxl8_world.c      |  59 +++++-
 src/pxl8_world.h      |   5 +-
 18 files changed, 1317 insertions(+), 127 deletions(-)
 create mode 100644 demo/mod/worldgen.fnl
 create mode 100644 src/pxl8_procgen.c
 create mode 100644 src/pxl8_procgen.h

diff --git a/demo/main.fnl b/demo/main.fnl
index 29b73ae..6228e39 100644
--- a/demo/main.fnl
+++ b/demo/main.fnl
@@ -1,9 +1,9 @@
 (local pxl8 (require :pxl8))
-(local bsp_world (require :mod.bsp_world))
 (local cube3d (require :mod.cube3d))
+(local worldgen (require :mod.worldgen))
 
 (var time 0)
-(var current-effect 1)
+(var active-demo :logo)
 (var particles nil)
 (var fire-init false)
 (var rain-init false)
@@ -17,103 +17,96 @@
 (var logo-sprite nil)
 
 (global init (fn []
-  (bsp_world.init)
   (cube3d.init)
+  (worldgen.init)
   (pxl8.load_palette "res/sprites/pxl8_logo.ase")
   (set logo-sprite (pxl8.load_sprite "res/sprites/pxl8_logo.ase"))
   (set particles (pxl8.particles_new 1000))))
 
 (global update (fn [dt]
-  (bsp_world.update dt)
   (set time (+ time dt))
 
-  (when (pxl8.key_pressed "1")
-    (set current-effect 1))
-  (when (pxl8.key_pressed "2")
-    (set current-effect 2))
-  (when (pxl8.key_pressed "3")
-    (set current-effect 3))
-  (when (pxl8.key_pressed "4")
-    (set current-effect 4))
+  (when (pxl8.key_pressed "1") (set active-demo :logo))
+  (when (pxl8.key_pressed "2") (set active-demo :plasma))
+  (when (pxl8.key_pressed "3") (set active-demo :tunnel))
+  (when (pxl8.key_pressed "4") (set active-demo :raster))
   (when (pxl8.key_pressed "5")
-    (set current-effect 5)
+    (set active-demo :fire)
     (set fire-init false))
   (when (pxl8.key_pressed "6")
-    (set current-effect 6)
+    (set active-demo :rain)
     (set rain-init false))
   (when (pxl8.key_pressed "7")
-    (set current-effect 7)
+    (set active-demo :snow)
     (set snow-init false))
-  (when (pxl8.key_pressed "8")
-    (set current-effect 8))
-  (when (pxl8.key_pressed "9")
-    (set current-effect 0))
-  (when (pxl8.key_pressed "0")
+  (when (pxl8.key_pressed "8") (set active-demo :cube3d))
+  (when (pxl8.key_pressed "9") (set active-demo :worldgen))
+  (when (pxl8.key_pressed "=")
     (set use-famicube-palette (not use-famicube-palette))
     (local palette-path (if use-famicube-palette "res/palettes/famicube.ase" "res/sprites/pxl8_logo.ase"))
     (pxl8.load_palette palette-path))
 
-  (case current-effect
-    1 (do
-        (set logo-x (+ logo-x (* logo-dx dt)))
-        (set logo-y (+ logo-y (* logo-dy dt)))
-        (when (or (< logo-x 0) (> logo-x 512))
-          (set logo-dx (- logo-dx)))
-        (when (or (< logo-y 0) (> logo-y 296))
-          (set logo-dy (- logo-dy))))
-    8 (cube3d.update dt)
-    _ nil)
+  (case active-demo
+    :logo (do
+            (set logo-x (+ logo-x (* logo-dx dt)))
+            (set logo-y (+ logo-y (* logo-dy dt)))
+            (when (or (< logo-x 0) (> logo-x 512))
+              (set logo-dx (- logo-dx)))
+            (when (or (< logo-y 0) (> logo-y 296))
+              (set logo-dy (- logo-dy))))
+    :cube3d (cube3d.update dt)
+    :worldgen (worldgen.update dt))
 
   (when particles
     (pxl8.particles_update particles dt))))
 
 (global frame (fn []
-  (case current-effect
-    0 (bsp_world.frame)
+  (case active-demo
+    :logo (do
+            (pxl8.clr 0)
+            (when logo-sprite
+              (pxl8.sprite logo-sprite logo-x logo-y 128 64)))
 
-    1 (do
-        (pxl8.clr 0)
-        (when logo-sprite
-          (pxl8.sprite logo-sprite logo-x logo-y 128 64)))
+    :plasma (pxl8.vfx_plasma time 0.10 0.04 1)
 
-    2 (pxl8.vfx_plasma time 0.10 0.04 1)
+    :tunnel (pxl8.vfx_tunnel time 2.0 0.25)
 
-    3 (pxl8.vfx_tunnel time 2.0 0.25)
+    :raster (do
+              (pxl8.clr 0)
+              (local bars [{:base_y 60 :amplitude 30 :height 16 :speed 2.0 :phase 0 :color 1 :fade_color 18}
+                           {:base_y 180 :amplitude 35 :height 16 :speed 1.8 :phase 2.0 :color 1 :fade_color 27}
+                           {:base_y 300 :amplitude 25 :height 16 :speed 2.2 :phase 4.0 :color 1 :fade_color 24}])
+              (pxl8.vfx_raster_bars bars time))
 
-    4 (do
-        (pxl8.clr 0)
-        (local bars [{:base_y 60 :amplitude 30 :height 16 :speed 2.0 :phase 0 :color 1 :fade_color 18}
-                     {:base_y 180 :amplitude 35 :height 16 :speed 1.8 :phase 2.0 :color 1 :fade_color 27}
-                     {:base_y 300 :amplitude 25 :height 16 :speed 2.2 :phase 4.0 :color 1 :fade_color 24}])
-        (pxl8.vfx_raster_bars bars time))
+    :fire (do
+            (pxl8.clr 0)
+            (when particles
+              (when (not fire-init)
+                (pxl8.particles_clear particles)
+                (pxl8.vfx_fire particles 160 140 100 12)
+                (set fire-init true))
+              (pxl8.particles_render particles)))
 
-    5 (do
-        (pxl8.clr 0)
-        (when particles
-          (when (not fire-init)
-            (pxl8.particles_clear particles)
-            (pxl8.vfx_fire particles 160 140 100 12)
-            (set fire-init true))
-          (pxl8.particles_render particles)))
+    :rain (do
+            (pxl8.clr 0)
+            (when particles
+              (when (not rain-init)
+                (pxl8.particles_clear particles)
+                (pxl8.vfx_rain particles 320 10.0)
+                (set rain-init true))
+              (pxl8.particles_render particles)))
 
-    6 (do
-        (pxl8.clr 0)
-        (when particles
-          (when (not rain-init)
-            (pxl8.particles_clear particles)
-            (pxl8.vfx_rain particles 320 10.0)
-            (set rain-init true))
-          (pxl8.particles_render particles)))
+    :snow (do
+            (pxl8.clr 0)
+            (when particles
+              (when (not snow-init)
+                (pxl8.particles_clear particles)
+                (pxl8.vfx_snow particles 320 5.0)
+                (set snow-init true))
+              (pxl8.particles_render particles)))
 
-    7 (do
-        (pxl8.clr 0)
-        (when particles
-          (when (not snow-init)
-            (pxl8.particles_clear particles)
-            (pxl8.vfx_snow particles 320 5.0)
-            (set snow-init true))
-          (pxl8.particles_render particles)))
+    :cube3d (cube3d.frame)
 
-    8 (cube3d.frame)
+    :worldgen (worldgen.frame)
 
     _ (pxl8.clr 0))))
diff --git a/demo/mod/worldgen.fnl b/demo/mod/worldgen.fnl
new file mode 100644
index 0000000..0519d88
--- /dev/null
+++ b/demo/mod/worldgen.fnl
@@ -0,0 +1,151 @@
+(local pxl8 (require :pxl8))
+(local debug-ui (require :mod.debug_ui))
+
+(var world nil)
+(var cam-x 1000)
+(var cam-y 64)
+(var cam-z 1000)
+(var cam-yaw 0)
+(var cam-pitch 0)
+(var bob-time 0)
+(var show-debug-ui false)
+(var affine false)
+(var fps 0)
+(var fps-accumulator 0)
+(var fps-frame-count 0)
+
+(local move-speed 200)
+(local turn-speed 2.0)
+(local bob-speed 8.0)
+(local bob-amount 4.0)
+
+(fn init []
+  (set world (pxl8.world_new))
+  (let [result (pxl8.world_generate world {
+                 :type pxl8.PROCGEN_CAVE
+                 :width 32
+                 :height 32
+                 :seed 42
+                 :density 0.45
+                 :iterations 4})]
+    (if (< result 0)
+        (pxl8.error (.. "Failed to generate cave - result: " result))
+        (pxl8.info "Generated procedural cave"))))
+
+(fn update [dt]
+  (set fps-accumulator (+ fps-accumulator dt))
+  (set fps-frame-count (+ fps-frame-count 1))
+
+  (when (>= fps-accumulator 0.25)
+    (set fps (/ fps-frame-count fps-accumulator))
+    (set fps-accumulator 0)
+    (set fps-frame-count 0))
+
+  (when (pxl8.key_pressed "F8")
+    (set show-debug-ui (not show-debug-ui))
+    (pxl8.ui_window_set_open "Debug Menu (F8)" show-debug-ui))
+
+  (when (pxl8.world_is_loaded world)
+    (let [forward-x (- (math.sin cam-yaw))
+          forward-z (- (math.cos cam-yaw))
+          right-x (math.cos cam-yaw)
+          right-z (- (math.sin cam-yaw))
+          cell-size 64
+          grid-min 0
+          grid-max (* 32 cell-size)]
+
+      (var moving false)
+      (var new-x cam-x)
+      (var new-z cam-z)
+
+      (when (pxl8.key_down "w")
+        (set new-x (+ new-x (* forward-x move-speed dt)))
+        (set new-z (+ new-z (* forward-z move-speed dt)))
+        (set moving true))
+
+      (when (pxl8.key_down "s")
+        (set new-x (- new-x (* forward-x move-speed dt)))
+        (set new-z (- new-z (* forward-z move-speed dt)))
+        (set moving true))
+
+      (when (pxl8.key_down "q")
+        (set new-x (- new-x (* right-x move-speed dt)))
+        (set new-z (- new-z (* right-z move-speed dt)))
+        (set moving true))
+
+      (when (pxl8.key_down "e")
+        (set new-x (+ new-x (* right-x move-speed dt)))
+        (set new-z (+ new-z (* right-z move-speed dt)))
+        (set moving true))
+
+      (when (and (>= new-x grid-min) (<= new-x grid-max)
+                 (>= new-z grid-min) (<= new-z grid-max))
+        (set cam-x new-x)
+        (set cam-z new-z))
+
+      (when (or (pxl8.key_down "left") (pxl8.key_down "a"))
+        (set cam-yaw (+ cam-yaw (* turn-speed dt))))
+
+      (when (or (pxl8.key_down "right") (pxl8.key_down "d"))
+        (set cam-yaw (- cam-yaw (* turn-speed dt))))
+
+      (when (pxl8.key_down "up")
+        (set cam-pitch (+ cam-pitch (* turn-speed dt)))
+        (when (> cam-pitch 1.5) (set cam-pitch 1.5)))
+
+      (when (pxl8.key_down "down")
+        (set cam-pitch (- cam-pitch (* turn-speed dt)))
+        (when (< cam-pitch -1.5) (set cam-pitch -1.5)))
+
+      (if moving
+          (set bob-time (+ bob-time (* dt bob-speed)))
+          (let [target-phase (* (math.floor (/ bob-time math.pi)) math.pi)]
+            (set bob-time (+ (* bob-time 0.8) (* target-phase 0.2))))))))
+
+(fn frame []
+  (pxl8.clr 0)
+
+  (when (pxl8.world_is_loaded world)
+    (let [bob-offset (* (math.sin bob-time) bob-amount)
+          eye-y (+ cam-y bob-offset)
+          forward-x (- (math.sin cam-yaw))
+          forward-z (- (math.cos cam-yaw))
+          target-x (+ cam-x forward-x)
+          target-y (+ eye-y (math.sin cam-pitch))
+          target-z (+ cam-z forward-z)]
+
+      (pxl8.text (.. "Pos: " (string.format "%.0f" cam-x) ","
+                     (string.format "%.0f" cam-y) ","
+                     (string.format "%.0f" cam-z)) 10 25 12)
+
+      (pxl8.clear_zbuffer)
+      (pxl8.set_backface_culling true)
+      (pxl8.set_wireframe false)
+
+      (let [aspect (/ (pxl8.get_width) (pxl8.get_height))
+            fov 1.047]
+        (pxl8.set_projection (pxl8.mat4_perspective fov aspect 1.0 4096.0)))
+
+      (pxl8.set_view (pxl8.mat4_lookat
+                       [cam-x eye-y cam-z]
+                       [target-x target-y target-z]
+                       [0 1 0]))
+
+      (pxl8.set_model (pxl8.mat4_identity))
+
+      (pxl8.set_affine_textures affine)
+      (pxl8.world_render world [cam-x eye-y cam-z]))
+
+    (let [new-state (debug-ui.render {:show-debug-ui show-debug-ui
+                                      :fps fps
+                                      :wireframe false
+                                      :auto-rotate false
+                                      :orthographic false
+                                      :use-texture true
+                                      :affine affine})]
+      (when (not= new-state.show-debug-ui nil) (set show-debug-ui new-state.show-debug-ui))
+      (when (not= new-state.affine nil) (set affine new-state.affine)))))
+
+{:init init
+ :update update
+ :frame frame}
diff --git a/src/lua/pxl8.lua b/src/lua/pxl8.lua
index fe04eff..65fddfe 100644
--- a/src/lua/pxl8.lua
+++ b/src/lua/pxl8.lua
@@ -459,4 +459,21 @@ function pxl8.world_is_loaded(world)
     return C.pxl8_world_is_loaded(world)
 end
 
+function pxl8.world_generate(world, params)
+    local c_params = ffi.new("pxl8_procgen_params")
+    c_params.type = params.type or C.PXL8_PROCGEN_CAVE
+    c_params.width = params.width or 32
+    c_params.height = params.height or 32
+    c_params.depth = params.depth or 0
+    c_params.seed = params.seed or 0
+    c_params.density = params.density or 0.45
+    c_params.iterations = params.iterations or 4
+    c_params.type_params = nil
+    return C.pxl8_world_generate(world, c_params)
+end
+
+pxl8.PROCGEN_CAVE = C.PXL8_PROCGEN_CAVE
+pxl8.PROCGEN_DUNGEON = C.PXL8_PROCGEN_DUNGEON
+pxl8.PROCGEN_TERRAIN = C.PXL8_PROCGEN_TERRAIN
+
 return pxl8
diff --git a/src/pxl8.c b/src/pxl8.c
index 7d7e4ee..6f7e5ca 100644
--- a/src/pxl8.c
+++ b/src/pxl8.c
@@ -147,6 +147,17 @@ pxl8_game_result pxl8_update(pxl8_game* game) {
     game->last_time = current_time;
     game->time += dt;
 
+    game->fps_accumulator += dt;
+    game->fps_frame_count++;
+    if (game->fps_accumulator >= 1.0f) {
+        game->fps = (f32)game->fps_frame_count / game->fps_accumulator;
+        if (!game->repl_mode) {
+            pxl8_debug("FPS: %.1f (%.2fms)", game->fps, (game->fps_accumulator / game->fps_frame_count) * 1000.0f);
+        }
+        game->fps_accumulator = 0.0f;
+        game->fps_frame_count = 0;
+    }
+
     pxl8_script_check_reload(game->script);
 
     if (game->repl_mode && !game->repl_started) {
diff --git a/src/pxl8_bsp.c b/src/pxl8_bsp.c
index a61d0f8..6b22818 100644
--- a/src/pxl8_bsp.c
+++ b/src/pxl8_bsp.c
@@ -1,3 +1,4 @@
+#include <math.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -331,7 +332,47 @@ bool pxl8_bsp_is_leaf_visible(const pxl8_bsp* bsp, i32 leaf_from, i32 leaf_to) {
     return (bsp->visdata[visofs + byte_idx] & (1 << bit_idx)) != 0;
 }
 
-void pxl8_bsp_render_face(pxl8_gfx* gfx, const pxl8_bsp* bsp, u32 face_id, u32 color) {
+static inline bool face_in_frustum(const pxl8_bsp* bsp, u32 face_id, const pxl8_frustum* frustum) {
+    const pxl8_bsp_face* face = &bsp->faces[face_id];
+
+    f32 min_x = 1e30f, min_y = 1e30f, min_z = 1e30f;
+    f32 max_x = -1e30f, max_y = -1e30f, max_z = -1e30f;
+
+    for (u32 i = 0; i < face->num_edges; i++) {
+        i32 surfedge_idx = face->first_edge + i;
+        if (surfedge_idx >= (i32)bsp->num_surfedges) continue;
+
+        i32 edge_idx = bsp->surfedges[surfedge_idx];
+        u32 vert_idx;
+
+        if (edge_idx >= 0) {
+            if ((u32)edge_idx >= bsp->num_edges) continue;
+            vert_idx = bsp->edges[edge_idx].vertex[0];
+        } else {
+            edge_idx = -edge_idx;
+            if ((u32)edge_idx >= bsp->num_edges) continue;
+            vert_idx = bsp->edges[edge_idx].vertex[1];
+        }
+
+        if (vert_idx >= bsp->num_vertices) continue;
+
+        pxl8_vec3 v = bsp->vertices[vert_idx].position;
+
+        if (v.x < min_x) min_x = v.x;
+        if (v.x > max_x) max_x = v.x;
+        if (v.y < min_y) min_y = v.y;
+        if (v.y > max_y) max_y = v.y;
+        if (v.z < min_z) min_z = v.z;
+        if (v.z > max_z) max_z = v.z;
+    }
+
+    pxl8_vec3 aabb_min = {min_x, min_y, min_z};
+    pxl8_vec3 aabb_max = {max_x, max_y, max_z};
+
+    return pxl8_frustum_test_aabb(frustum, aabb_min, aabb_max);
+}
+
+void pxl8_bsp_render_face(pxl8_gfx* gfx, const pxl8_bsp* bsp, u32 face_id, u32 texture_id) {
     if (!gfx || !bsp || face_id >= bsp->num_faces) return;
 
     const pxl8_bsp_face* face = &bsp->faces[face_id];
@@ -340,6 +381,19 @@ void pxl8_bsp_render_face(pxl8_gfx* gfx, const pxl8_bsp* bsp, u32 face_id, u32 c
     pxl8_vec3 verts[64];
     u32 num_verts = 0;
 
+    const pxl8_bsp_plane* plane = &bsp->planes[face->plane_id];
+
+    u32 color;
+    bool use_texture = false;
+
+    if (fabsf(plane->normal.y) > 0.7f) {
+        color = (plane->normal.y > 0) ? 4 : 3;
+    } else {
+        color = 15;
+        use_texture = (texture_id > 0);
+    }
+
+
     for (u32 i = 0; i < face->num_edges && num_verts < 64; i++) {
         i32 surfedge_idx = face->first_edge + i;
         if (surfedge_idx >= (i32)bsp->num_surfedges) continue;
@@ -362,11 +416,77 @@ void pxl8_bsp_render_face(pxl8_gfx* gfx, const pxl8_bsp* bsp, u32 face_id, u32 c
 
     if (num_verts < 3) return;
 
-    for (u32 i = 1; i < num_verts - 1; i++) {
-        pxl8_3d_draw_triangle_raw(gfx, verts[0], verts[i], verts[i + 1], color);
+    if (use_texture && face->texinfo_id < bsp->num_texinfo) {
+        const pxl8_bsp_texinfo* texinfo = &bsp->texinfo[face->texinfo_id];
+        f32 tex_scale = 64.0f;
+
+        for (u32 tri_idx = 1; tri_idx < num_verts - 1; tri_idx++) {
+            pxl8_vec3 v0 = verts[0];
+            pxl8_vec3 v1 = verts[tri_idx];
+            pxl8_vec3 v2 = verts[tri_idx + 1];
+
+            f32 u0 = (pxl8_vec3_dot(v0, texinfo->u_axis) + texinfo->u_offset) / tex_scale;
+            f32 v0_uv = (pxl8_vec3_dot(v0, texinfo->v_axis) + texinfo->v_offset) / tex_scale;
+            f32 u1 = (pxl8_vec3_dot(v1, texinfo->u_axis) + texinfo->u_offset) / tex_scale;
+            f32 v1_uv = (pxl8_vec3_dot(v1, texinfo->v_axis) + texinfo->v_offset) / tex_scale;
+            f32 u2 = (pxl8_vec3_dot(v2, texinfo->u_axis) + texinfo->u_offset) / tex_scale;
+            f32 v2_uv = (pxl8_vec3_dot(v2, texinfo->v_axis) + texinfo->v_offset) / tex_scale;
+
+            pxl8_3d_draw_triangle_textured(gfx, v0, v1, v2, u0, v0_uv, u1, v1_uv, u2, v2_uv, texture_id);
+        }
+    } else{
+        for (u32 i = 1; i < num_verts - 1; i++) {
+            pxl8_3d_draw_triangle_raw(gfx, verts[0], verts[i], verts[i + 1], color);
+        }
     }
 }
 
+void pxl8_bsp_render_solid(
+    pxl8_gfx* gfx,
+    const pxl8_bsp* bsp,
+    pxl8_vec3 camera_pos,
+    u32 texture_id
+) {
+    if (!gfx || !bsp || bsp->num_faces == 0) return;
+
+    const pxl8_frustum* frustum = pxl8_3d_get_frustum(gfx);
+    if (!frustum) return;
+
+    i32 camera_leaf = pxl8_bsp_find_leaf(bsp, camera_pos);
+
+    static u8* rendered_faces = NULL;
+    static u32 rendered_faces_capacity = 0;
+
+    if (rendered_faces_capacity < bsp->num_faces) {
+        rendered_faces = realloc(rendered_faces, bsp->num_faces);
+        if (!rendered_faces) return;
+        rendered_faces_capacity = bsp->num_faces;
+        pxl8_debug("Allocated face tracking buffer: %u bytes", bsp->num_faces);
+    }
+
+    memset(rendered_faces, 0, bsp->num_faces);
+
+    for (u32 leaf_id = 0; leaf_id < bsp->num_leafs; leaf_id++) {
+        if (camera_leaf >= 0 && !pxl8_bsp_is_leaf_visible(bsp, camera_leaf, leaf_id)) continue;
+
+        const pxl8_bsp_leaf* leaf = &bsp->leafs[leaf_id];
+
+        for (u32 i = 0; i < leaf->num_marksurfaces; i++) {
+            u32 surf_idx = leaf->first_marksurface + i;
+            if (surf_idx >= bsp->num_marksurfaces) continue;
+
+            u32 face_id = bsp->marksurfaces[surf_idx];
+            if (face_id >= bsp->num_faces) continue;
+
+            if (rendered_faces[face_id]) continue;
+            rendered_faces[face_id] = 1;
+
+            pxl8_bsp_render_face(gfx, bsp, face_id, texture_id);
+        }
+    }
+
+}
+
 void pxl8_bsp_render_wireframe(
     pxl8_gfx* gfx,
     const pxl8_bsp* bsp,
diff --git a/src/pxl8_bsp.h b/src/pxl8_bsp.h
index 5fc1273..74cfbc1 100644
--- a/src/pxl8_bsp.h
+++ b/src/pxl8_bsp.h
@@ -115,7 +115,14 @@ void pxl8_bsp_render_face(
     pxl8_gfx* gfx,
     const pxl8_bsp* bsp,
     u32 face_id,
-    u32 color
+    u32 texture_id
+);
+
+void pxl8_bsp_render_solid(
+    pxl8_gfx* gfx,
+    const pxl8_bsp* bsp,
+    pxl8_vec3 camera_pos,
+    u32 texture_id
 );
 
 void pxl8_bsp_render_wireframe(
diff --git a/src/pxl8_game.h b/src/pxl8_game.h
index 8d9b865..0077915 100644
--- a/src/pxl8_game.h
+++ b/src/pxl8_game.h
@@ -27,6 +27,10 @@ typedef struct pxl8_game {
     u64 last_time;
     f32 time;
 
+    f32 fps_accumulator;
+    i32 fps_frame_count;
+    f32 fps;
+
     bool repl_mode;
     bool repl_started;
     bool running;
diff --git a/src/pxl8_gfx.c b/src/pxl8_gfx.c
index 668dd34..1089c64 100644
--- a/src/pxl8_gfx.c
+++ b/src/pxl8_gfx.c
@@ -42,12 +42,18 @@ struct pxl8_gfx {
     pxl8_mat4 model;
     pxl8_mat4 projection;
     pxl8_mat4 view;
+    pxl8_mat4 mvp;
+    bool mvp_dirty;
+    pxl8_frustum frustum;
     bool wireframe;
     f32* zbuffer;
     i32 zbuffer_height;
     i32 zbuffer_width;
 
     bool affine_textures;
+
+    u32 frame_triangle_count;
+    u32 frame_pixel_count;
 };
 
 static inline void pxl8_color_unpack(u32 color, u8* r, u8* g, u8* b, u8* a) {
@@ -191,6 +197,7 @@ pxl8_gfx* pxl8_gfx_create(
     gfx->model = pxl8_mat4_identity();
     gfx->projection = pxl8_mat4_identity();
     gfx->view = pxl8_mat4_identity();
+    gfx->mvp_dirty = true;
     gfx->wireframe = false;
     gfx->zbuffer = NULL;
     gfx->zbuffer_height = 0;
@@ -403,10 +410,23 @@ void pxl8_gfx_project(pxl8_gfx* gfx, f32 left, f32 right, f32 top, f32 bottom) {
 
 void pxl8_clr(pxl8_gfx* gfx, u32 color) {
     if (!gfx || !gfx->framebuffer) return;
-    
+
+    static u32 frame_count = 0;
+    if (gfx->frame_triangle_count > 0) {
+        if (frame_count % 60 == 0) {
+            i32 fb_pixels = gfx->framebuffer_width * gfx->framebuffer_height;
+            f32 overdraw = (f32)gfx->frame_pixel_count / (f32)fb_pixels;
+            pxl8_debug("Frame triangles: %u, pixels: %u, overdraw: %.2fx",
+                      gfx->frame_triangle_count, gfx->frame_pixel_count, overdraw);
+        }
+        frame_count++;
+    }
+    gfx->frame_triangle_count = 0;
+    gfx->frame_pixel_count = 0;
+
     i32 bytes_per_pixel = (gfx->color_mode == PXL8_COLOR_MODE_HICOLOR) ? 4 : 1;
     i32 size = gfx->framebuffer_width * gfx->framebuffer_height;
-    
+
     if (bytes_per_pixel == 4) {
         u32* fb32 = (u32*)gfx->framebuffer;
         for (i32 i = 0; i < size; i++) {
@@ -786,9 +806,33 @@ static bool pxl8_3d_init_zbuffer(pxl8_gfx* gfx) {
 
 void pxl8_3d_clear_zbuffer(pxl8_gfx* gfx) {
     if (!gfx || !gfx->zbuffer) return;
-    for (i32 i = 0; i < gfx->zbuffer_width * gfx->zbuffer_height; i++) {
-        gfx->zbuffer[i] = 1e30f;
+
+    i32 count = gfx->zbuffer_width * gfx->zbuffer_height;
+    const f32 far_z = 1e30f;
+
+#if defined(PXL8_SIMD_NEON)
+    float32x4_t far_vec = vdupq_n_f32(far_z);
+    i32 i = 0;
+    for (; i + 3 < count; i += 4) {
+        vst1q_f32(&gfx->zbuffer[i], far_vec);
     }
+    for (; i < count; i++) {
+        gfx->zbuffer[i] = far_z;
+    }
+#elif defined(PXL8_SIMD_SSE2)
+    __m128 far_vec = _mm_set1_ps(far_z);
+    i32 i = 0;
+    for (; i + 3 < count; i += 4) {
+        _mm_store_ps(&gfx->zbuffer[i], far_vec);
+    }
+    for (; i < count; i++) {
+        gfx->zbuffer[i] = far_z;
+    }
+#else
+    for (i32 i = 0; i < count; i++) {
+        gfx->zbuffer[i] = far_z;
+    }
+#endif
 }
 
 void pxl8_3d_set_backface_culling(pxl8_gfx* gfx, bool culling) {
@@ -799,16 +843,19 @@ void pxl8_3d_set_backface_culling(pxl8_gfx* gfx, bool culling) {
 void pxl8_3d_set_model(pxl8_gfx* gfx, pxl8_mat4 mat) {
     if (!gfx) return;
     gfx->model = mat;
+    gfx->mvp_dirty = true;
 }
 
 void pxl8_3d_set_projection(pxl8_gfx* gfx, pxl8_mat4 mat) {
     if (!gfx) return;
     gfx->projection = mat;
+    gfx->mvp_dirty = true;
 }
 
 void pxl8_3d_set_view(pxl8_gfx* gfx, pxl8_mat4 mat) {
     if (!gfx) return;
     gfx->view = mat;
+    gfx->mvp_dirty = true;
 }
 
 void pxl8_3d_set_wireframe(pxl8_gfx* gfx, bool wireframe) {
@@ -821,7 +868,27 @@ void pxl8_3d_set_affine_textures(pxl8_gfx* gfx, bool affine) {
     gfx->affine_textures = affine;
 }
 
+static inline void pxl8_update_mvp(pxl8_gfx* gfx) {
+    if (!gfx->mvp_dirty) return;
+
+    gfx->mvp = pxl8_mat4_multiply(gfx->projection,
+                pxl8_mat4_multiply(gfx->view, gfx->model));
+
+    pxl8_mat4 vp = pxl8_mat4_multiply(gfx->projection, gfx->view);
+    gfx->frustum = pxl8_frustum_from_matrix(vp);
+
+    gfx->mvp_dirty = false;
+}
+
+const pxl8_frustum* pxl8_3d_get_frustum(pxl8_gfx* gfx) {
+    if (!gfx) return NULL;
+    pxl8_update_mvp(gfx);
+    return &gfx->frustum;
+}
+
 static inline pxl8_vec4 pxl8_transform_vertex(pxl8_gfx* gfx, pxl8_vec3 pos) {
+    pxl8_update_mvp(gfx);
+
     pxl8_vec4 v = {
         .x = pos.x,
         .y = pos.y,
@@ -829,10 +896,7 @@ static inline pxl8_vec4 pxl8_transform_vertex(pxl8_gfx* gfx, pxl8_vec3 pos) {
         .w = 1.0f,
     };
 
-    pxl8_mat4 mvp = pxl8_mat4_multiply(gfx->projection,
-                    pxl8_mat4_multiply(gfx->view, gfx->model));
-
-    return pxl8_mat4_multiply_vec4(mvp, v);
+    return pxl8_mat4_multiply_vec4(gfx->mvp, v);
 }
 
 static inline void pxl8_project_to_screen(pxl8_gfx* gfx, pxl8_vec4 clip, i32* x, i32* y, f32* z) {
@@ -865,23 +929,82 @@ void pxl8_3d_draw_line_3d(pxl8_gfx* gfx, pxl8_vec3 p0, pxl8_vec3 p1, u32 color)
     pxl8_line(gfx, x0, y0, x1, y1, color);
 }
 
-static inline void pxl8_fill_scanline(pxl8_gfx* gfx, i32 y, i32 xs, i32 xe, f32 z0, f32 z1, u32 color) {
+static inline void pxl8_fill_scanline_hicolor(pxl8_gfx* gfx, i32 y, i32 xs, i32 xe, f32 z0, f32 z1, u32 color) {
     if (y < 0 || y >= gfx->framebuffer_height) return;
     if (xs > xe) {
         i32 tmp = xs; xs = xe; xe = tmp;
+        f32 tmpz = z0; z0 = z1; z1 = tmpz;
     }
 
-    for (i32 x = xs; x <= xe; x++) {
-        if (x >= 0 && x < gfx->framebuffer_width) {
-            f32 t = (xe == xs) ? 0.0f : (f32)(x - xs) / (f32)(xe - xs);
-            f32 z = z0 + t * (z1 - z0);
+    if (xs < 0) xs = 0;
+    if (xe >= gfx->framebuffer_width) xe = gfx->framebuffer_width - 1;
+    if (xs > xe) return;
 
-            i32 idx = y * gfx->zbuffer_width + x;
-            if (z <= gfx->zbuffer[idx]) {
-                gfx->zbuffer[idx] = z;
-                pxl8_pixel(gfx, x, y, color);
-            }
+    i32 width = xe - xs;
+    if (width == 0) {
+        i32 idx = y * gfx->zbuffer_width + xs;
+        if (z0 <= gfx->zbuffer[idx]) {
+            gfx->zbuffer[idx] = z0;
+            i32 fb_idx = y * gfx->framebuffer_width + xs;
+            ((u32*)gfx->framebuffer)[fb_idx] = color;
         }
+        return;
+    }
+
+    f32 dz = (z1 - z0) / (f32)width;
+    f32 z = z0;
+
+    i32 zbuf_offset = y * gfx->zbuffer_width;
+    i32 fb_offset = y * gfx->framebuffer_width;
+    u32* fb = (u32*)gfx->framebuffer;
+
+    for (i32 x = xs; x <= xe; x++) {
+        i32 idx = zbuf_offset + x;
+        if (z <= gfx->zbuffer[idx]) {
+            gfx->zbuffer[idx] = z;
+            fb[fb_offset + x] = color;
+        }
+        z += dz;
+    }
+}
+
+static inline void pxl8_fill_scanline_indexed(pxl8_gfx* gfx, i32 y, i32 xs, i32 xe, f32 z0, f32 z1, u32 color) {
+    if (y < 0 || y >= gfx->framebuffer_height) return;
+    if (xs > xe) {
+        i32 tmp = xs; xs = xe; xe = tmp;
+        f32 tmpz = z0; z0 = z1; z1 = tmpz;
+    }
+
+    if (xs < 0) xs = 0;
+    if (xe >= gfx->framebuffer_width) xe = gfx->framebuffer_width - 1;
+    if (xs > xe) return;
+
+    i32 width = xe - xs;
+    u8 idx_color = color & 0xFF;
+
+    if (width == 0) {
+        i32 idx = y * gfx->zbuffer_width + xs;
+        if (z0 <= gfx->zbuffer[idx]) {
+            gfx->zbuffer[idx] = z0;
+            i32 fb_idx = y * gfx->framebuffer_width + xs;
+            gfx->framebuffer[fb_idx] = idx_color;
+        }
+        return;
+    }
+
+    f32 dz = (z1 - z0) / (f32)width;
+    f32 z = z0;
+
+    i32 zbuf_offset = y * gfx->zbuffer_width;
+    i32 fb_offset = y * gfx->framebuffer_width;
+
+    for (i32 x = xs; x <= xe; x++) {
+        i32 idx = zbuf_offset + x;
+        if (z <= gfx->zbuffer[idx]) {
+            gfx->zbuffer[idx] = z;
+            gfx->framebuffer[fb_offset + x] = idx_color;
+        }
+        z += dz;
     }
 }
 
@@ -927,47 +1050,117 @@ static inline void pxl8_fill_scanline_textured(
         tmpf = w0; w0 = w1; w1 = tmpf;
     }
 
-    for (i32 x = xs; x <= xe; x++) {
-        if (x >= 0 && x < gfx->framebuffer_width) {
-            f32 t = (xe == xs) ? 0.0f : (f32)(x - xs) / (f32)(xe - xs);
-            f32 z = z0 + t * (z1 - z0);
-
-            i32 idx = y * gfx->zbuffer_width + x;
-            if (z <= gfx->zbuffer[idx]) {
-                f32 u = u0 + t * (u1 - u0);
-                f32 v = v0 + t * (v1 - v0);
-
-                if (!gfx->affine_textures) {
-                    f32 w = w0 + t * (w1 - w0);
-                    if (fabsf(w) > 1e-6f) {
-                        u /= w;
-                        v /= w;
-                    }
+    i32 span = xe - xs;
+    if (span <= 0) {
+        if (xs >= 0 && xs < gfx->framebuffer_width) {
+            i32 idx = y * gfx->zbuffer_width + xs;
+            if (z0 <= gfx->zbuffer[idx]) {
+                gfx->frame_pixel_count++;
+                f32 u = u0, v = v0;
+                if (!gfx->affine_textures && fabsf(w0) > 1e-6f) {
+                    u /= w0;
+                    v /= w0;
                 }
-
                 u32 color = pxl8_sample_texture(gfx, texture_id, u, v);
-                if (gfx->color_mode == PXL8_COLOR_MODE_HICOLOR) {
-                    if (color & 0xFF000000) {
-                        gfx->zbuffer[idx] = z;
-                        pxl8_pixel(gfx, x, y, color);
-                    }
-                } else {
-                    if (color != 0) {
+                if ((gfx->color_mode == PXL8_COLOR_MODE_HICOLOR && (color & 0xFF000000)) ||
+                    (gfx->color_mode != PXL8_COLOR_MODE_HICOLOR && color != 0)) {
+                    gfx->zbuffer[idx] = z0;
+                    pxl8_pixel(gfx, xs, y, color);
+                }
+            }
+        }
+        return;
+    }
+
+    f32 inv_span = 1.0f / (f32)span;
+    f32 dz = (z1 - z0) * inv_span;
+    f32 du = (u1 - u0) * inv_span;
+    f32 dv = (v1 - v0) * inv_span;
+    f32 dw = (w1 - w0) * inv_span;
+
+    f32 z = z0;
+    f32 u = u0;
+    f32 v = v0;
+    f32 w = w0;
+
+    if (gfx->affine_textures) {
+        for (i32 x = xs; x <= xe; x++) {
+            if (x >= 0 && x < gfx->framebuffer_width) {
+                i32 idx = y * gfx->zbuffer_width + x;
+                if (z <= gfx->zbuffer[idx]) {
+                    gfx->frame_pixel_count++;
+                    u32 color = pxl8_sample_texture(gfx, texture_id, u, v);
+                    if ((gfx->color_mode == PXL8_COLOR_MODE_HICOLOR && (color & 0xFF000000)) ||
+                        (gfx->color_mode != PXL8_COLOR_MODE_HICOLOR && color != 0)) {
                         gfx->zbuffer[idx] = z;
                         pxl8_pixel(gfx, x, y, color);
                     }
                 }
             }
+            z += dz;
+            u += du;
+            v += dv;
+        }
+    } else {
+        i32 x = xs;
+        while (x <= xe) {
+            f32 w_inv = (fabsf(w) > 1e-6f) ? (1.0f / w) : 0.0f;
+            f32 u_corrected = u * w_inv;
+            f32 v_corrected = v * w_inv;
+
+            i32 span_end = (x + 16 <= xe) ? (x + 16) : (xe + 1);
+            i32 span_len = span_end - x;
+
+            f32 next_u, next_v, affine_du, affine_dv;
+            if (span_len > 1) {
+                f32 next_w = w + span_len * dw;
+                f32 next_w_inv = (fabsf(next_w) > 1e-6f) ? (1.0f / next_w) : 0.0f;
+                next_u = (u + span_len * du) * next_w_inv;
+                next_v = (v + span_len * dv) * next_w_inv;
+                f32 inv_span = 1.0f / (f32)span_len;
+                affine_du = (next_u - u_corrected) * inv_span;
+                affine_dv = (next_v - v_corrected) * inv_span;
+            } else {
+                affine_du = 0;
+                affine_dv = 0;
+            }
+
+            f32 affine_u = u_corrected;
+            f32 affine_v = v_corrected;
+
+            for (; x < span_end; x++) {
+                if (x >= 0 && x < gfx->framebuffer_width) {
+                    i32 idx = y * gfx->zbuffer_width + x;
+                    if (z <= gfx->zbuffer[idx]) {
+                        gfx->frame_pixel_count++;
+                        u32 color = pxl8_sample_texture(gfx, texture_id, affine_u, affine_v);
+                        if ((gfx->color_mode == PXL8_COLOR_MODE_HICOLOR && (color & 0xFF000000)) ||
+                            (gfx->color_mode != PXL8_COLOR_MODE_HICOLOR && color != 0)) {
+                            gfx->zbuffer[idx] = z;
+                            pxl8_pixel(gfx, x, y, color);
+                        }
+                    }
+                }
+                z += dz;
+                u += du;
+                v += dv;
+                w += dw;
+                affine_u += affine_du;
+                affine_v += affine_dv;
+            }
         }
     }
 }
 
+typedef void (*pxl8_scanline_func)(pxl8_gfx*, i32, i32, i32, f32, f32, u32);
+
 static void pxl8_draw_flat_bottom_triangle(
     pxl8_gfx* gfx,
     i32 x0, i32 y0, f32 z0,
     i32 x1, i32 y1, f32 z1,
     i32 x2, i32 y2, f32 z2,
-    u32 color
+    u32 color,
+    pxl8_scanline_func fill_scanline
 ) {
     (void)z2;
     if (y1 == y0) return;
@@ -979,7 +1172,7 @@ static void pxl8_draw_flat_bottom_triangle(
     f32 cur_x2 = (f32)x0;
 
     for (i32 y = y0; y <= y1; y++) {
-        pxl8_fill_scanline(gfx, y, (i32)cur_x1, (i32)cur_x2, z0, z1, color);
+        fill_scanline(gfx, y, (i32)cur_x1, (i32)cur_x2, z0, z1, color);
         cur_x1 += inv_slope_1;
         cur_x2 += inv_slope_2;
     }
@@ -990,7 +1183,8 @@ static void pxl8_draw_flat_top_triangle(
     i32 x0, i32 y0, f32 z0,
     i32 x1, i32 y1, f32 z1,
     i32 x2, i32 y2, f32 z2,
-    u32 color
+    u32 color,
+    pxl8_scanline_func fill_scanline
 ) {
     (void)z2;
     if (y2 == y0) return;
@@ -1002,7 +1196,7 @@ static void pxl8_draw_flat_top_triangle(
     f32 cur_x2 = (f32)x2;
 
     for (i32 y = y2; y > y0; y--) {
-        pxl8_fill_scanline(gfx, y, (i32)cur_x1, (i32)cur_x2, z0, z1, color);
+        fill_scanline(gfx, y, (i32)cur_x1, (i32)cur_x2, z0, z1, color);
         cur_x1 -= inv_slope_1;
         cur_x2 -= inv_slope_2;
     }
@@ -1022,6 +1216,8 @@ void pxl8_3d_draw_triangle_raw(pxl8_gfx* gfx, pxl8_vec3 v0, pxl8_vec3 v1, pxl8_v
 void pxl8_3d_draw_triangle(pxl8_gfx* gfx, pxl8_triangle tri) {
     if (!gfx || !pxl8_3d_init_zbuffer(gfx)) return;
 
+    gfx->frame_triangle_count++;
+
     pxl8_vec4 v0 = pxl8_transform_vertex(gfx, tri.v[0].position);
     pxl8_vec4 v1 = pxl8_transform_vertex(gfx, tri.v[1].position);
     pxl8_vec4 v2 = pxl8_transform_vertex(gfx, tri.v[2].position);
@@ -1065,17 +1261,21 @@ void pxl8_3d_draw_triangle(pxl8_gfx* gfx, pxl8_triangle tri) {
 
     u32 color = tri.v[0].color;
 
+    pxl8_scanline_func fill_scanline = (gfx->color_mode == PXL8_COLOR_MODE_HICOLOR)
+        ? pxl8_fill_scanline_hicolor
+        : pxl8_fill_scanline_indexed;
+
     if (y1 == y2) {
-        pxl8_draw_flat_bottom_triangle(gfx, x0, y0, z0, x1, y1, z1, x2, y2, z2, color);
+        pxl8_draw_flat_bottom_triangle(gfx, x0, y0, z0, x1, y1, z1, x2, y2, z2, color, fill_scanline);
     } else if (y0 == y1) {
-        pxl8_draw_flat_top_triangle(gfx, x0, y0, z0, x1, y1, z1, x2, y2, z2, color);
+        pxl8_draw_flat_top_triangle(gfx, x0, y0, z0, x1, y1, z1, x2, y2, z2, color, fill_scanline);
     } else {
         i32 x3 = x0 + (i32)(((f32)(y1 - y0) / (f32)(y2 - y0)) * (x2 - x0));
         i32 y3 = y1;
         f32 z3 = z0 + ((f32)(y1 - y0) / (f32)(y2 - y0)) * (z2 - z0);
 
-        pxl8_draw_flat_bottom_triangle(gfx, x0, y0, z0, x1, y1, z1, x3, y3, z3, color);
-        pxl8_draw_flat_top_triangle(gfx, x1, y1, z1, x3, y3, z3, x2, y2, z2, color);
+        pxl8_draw_flat_bottom_triangle(gfx, x0, y0, z0, x1, y1, z1, x3, y3, z3, color, fill_scanline);
+        pxl8_draw_flat_top_triangle(gfx, x1, y1, z1, x3, y3, z3, x2, y2, z2, color, fill_scanline);
     }
 }
 
diff --git a/src/pxl8_gfx.h b/src/pxl8_gfx.h
index f989445..933d108 100644
--- a/src/pxl8_gfx.h
+++ b/src/pxl8_gfx.h
@@ -101,6 +101,7 @@ void pxl8_3d_draw_line_3d(pxl8_gfx* gfx, pxl8_vec3 p0, pxl8_vec3 p1, u32 color);
 void pxl8_3d_draw_triangle(pxl8_gfx* gfx, pxl8_triangle tri);
 void pxl8_3d_draw_triangle_raw(pxl8_gfx* gfx, pxl8_vec3 v0, pxl8_vec3 v1, pxl8_vec3 v2, u32 color);
 void pxl8_3d_draw_triangle_textured(pxl8_gfx* gfx, pxl8_vec3 v0, pxl8_vec3 v1, pxl8_vec3 v2, f32 u0, f32 v0f, f32 u1, f32 v1f, f32 u2, f32 v2f, u32 texture_id);
+const pxl8_frustum* pxl8_3d_get_frustum(pxl8_gfx* gfx);
 void pxl8_3d_set_affine_textures(pxl8_gfx* gfx, bool affine);
 void pxl8_3d_set_backface_culling(pxl8_gfx* gfx, bool culling);
 void pxl8_3d_set_model(pxl8_gfx* gfx, pxl8_mat4 mat);
diff --git a/src/pxl8_io.c b/src/pxl8_io.c
index b32441f..2eacef1 100644
--- a/src/pxl8_io.c
+++ b/src/pxl8_io.c
@@ -115,6 +115,7 @@ static i32 pxl8_key_code(const char* key_name) {
         {"1", 30}, {"2", 31}, {"3", 32}, {"4", 33}, {"5", 34},
         {"6", 35}, {"7", 36}, {"8", 37}, {"9", 38}, {"0", 39},
         {"return", 40}, {"escape", 41}, {"backspace", 42}, {"tab", 43}, {"space", 44},
+        {"-", 45}, {"=", 46},
         {"left", 80}, {"right", 79}, {"up", 82}, {"down", 81},
         {"f1", 58}, {"f2", 59}, {"f3", 60}, {"f4", 61}, {"f5", 62}, {"f6", 63},
         {"f7", 64}, {"f8", 65}, {"f9", 66}, {"f10", 67}, {"f11", 68}, {"f12", 69},
diff --git a/src/pxl8_math.c b/src/pxl8_math.c
index 60016e2..37b8006 100644
--- a/src/pxl8_math.c
+++ b/src/pxl8_math.c
@@ -250,3 +250,70 @@ pxl8_mat4 pxl8_mat4_lookat(pxl8_vec3 eye, pxl8_vec3 center, pxl8_vec3 up) {
 
     return mat;
 }
+
+pxl8_frustum pxl8_frustum_from_matrix(pxl8_mat4 vp) {
+    pxl8_frustum frustum;
+    const f32* m = vp.m;
+
+    frustum.planes[0].normal.x = m[3] - m[0];
+    frustum.planes[0].normal.y = m[7] - m[4];
+    frustum.planes[0].normal.z = m[11] - m[8];
+    frustum.planes[0].distance = m[15] - m[12];
+
+    frustum.planes[1].normal.x = m[3] + m[0];
+    frustum.planes[1].normal.y = m[7] + m[4];
+    frustum.planes[1].normal.z = m[11] + m[8];
+    frustum.planes[1].distance = m[15] + m[12];
+
+    frustum.planes[2].normal.x = m[3] + m[1];
+    frustum.planes[2].normal.y = m[7] + m[5];
+    frustum.planes[2].normal.z = m[11] + m[9];
+    frustum.planes[2].distance = m[15] + m[13];
+
+    frustum.planes[3].normal.x = m[3] - m[1];
+    frustum.planes[3].normal.y = m[7] - m[5];
+    frustum.planes[3].normal.z = m[11] - m[9];
+    frustum.planes[3].distance = m[15] - m[13];
+
+    frustum.planes[4].normal.x = m[3] - m[2];
+    frustum.planes[4].normal.y = m[7] - m[6];
+    frustum.planes[4].normal.z = m[11] - m[10];
+    frustum.planes[4].distance = m[15] - m[14];
+
+    frustum.planes[5].normal.x = m[3] + m[2];
+    frustum.planes[5].normal.y = m[7] + m[6];
+    frustum.planes[5].normal.z = m[11] + m[10];
+    frustum.planes[5].distance = m[15] + m[14];
+
+    for (i32 i = 0; i < 6; i++) {
+        f32 len = pxl8_vec3_length(frustum.planes[i].normal);
+        if (len > 1e-6f) {
+            f32 inv_len = 1.0f / len;
+            frustum.planes[i].normal = pxl8_vec3_scale(frustum.planes[i].normal, inv_len);
+            frustum.planes[i].distance *= inv_len;
+        }
+    }
+
+    return frustum;
+}
+
+bool pxl8_frustum_test_aabb(const pxl8_frustum* frustum, pxl8_vec3 min, pxl8_vec3 max) {
+    for (i32 i = 0; i < 6; i++) {
+        pxl8_vec3 normal = frustum->planes[i].normal;
+        f32 d = frustum->planes[i].distance;
+
+        pxl8_vec3 p_vertex = {
+            (normal.x >= 0.0f) ? max.x : min.x,
+            (normal.y >= 0.0f) ? max.y : min.y,
+            (normal.z >= 0.0f) ? max.z : min.z
+        };
+
+        f32 dist = pxl8_vec3_dot(normal, p_vertex) + d;
+
+        if (dist < 0.0f) {
+            return false;
+        }
+    }
+
+    return true;
+}
diff --git a/src/pxl8_math.h b/src/pxl8_math.h
index e10f17d..773cb9a 100644
--- a/src/pxl8_math.h
+++ b/src/pxl8_math.h
@@ -18,6 +18,15 @@ typedef struct pxl8_mat4 {
     f32 m[16];
 } pxl8_mat4;
 
+typedef struct pxl8_plane {
+    pxl8_vec3 normal;
+    f32 distance;
+} pxl8_plane;
+
+typedef struct pxl8_frustum {
+    pxl8_plane planes[6];
+} pxl8_frustum;
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -49,6 +58,9 @@ pxl8_mat4 pxl8_mat4_rotate_z(f32 angle);
 pxl8_mat4 pxl8_mat4_scale(f32 x, f32 y, f32 z);
 pxl8_mat4 pxl8_mat4_translate(f32 x, f32 y, f32 z);
 
+pxl8_frustum pxl8_frustum_from_matrix(pxl8_mat4 vp);
+bool pxl8_frustum_test_aabb(const pxl8_frustum* frustum, pxl8_vec3 min, pxl8_vec3 max);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/pxl8_procgen.c b/src/pxl8_procgen.c
new file mode 100644
index 0000000..38ff452
--- /dev/null
+++ b/src/pxl8_procgen.c
@@ -0,0 +1,472 @@
+#include "pxl8_procgen.h"
+
+#include "pxl8_macros.h"
+
+#include <math.h>
+#include <stdlib.h>
+#include <string.h>
+
+typedef struct cave_grid {
+    u8* cells;
+    i32 width;
+    i32 height;
+} cave_grid;
+
+static u32 prng_state = 0;
+
+static void prng_seed(u32 seed) {
+    prng_state = seed;
+}
+
+static u32 prng_next(void) {
+    prng_state ^= prng_state << 13;
+    prng_state ^= prng_state >> 17;
+    prng_state ^= prng_state << 5;
+    return prng_state;
+}
+
+static f32 prng_float(void) {
+    return (f32)prng_next() / (f32)0xFFFFFFFF;
+}
+
+static cave_grid* cave_grid_create(i32 width, i32 height) {
+    cave_grid* grid = malloc(sizeof(cave_grid));
+    if (!grid) return NULL;
+
+    grid->width = width;
+    grid->height = height;
+    grid->cells = calloc(width * height, sizeof(u8));
+
+    if (!grid->cells) {
+        free(grid);
+        return NULL;
+    }
+
+    return grid;
+}
+
+static void cave_grid_destroy(cave_grid* grid) {
+    if (!grid) return;
+    free(grid->cells);
+    free(grid);
+}
+
+static u8 cave_grid_get(const cave_grid* grid, i32 x, i32 y) {
+    if (x < 0 || x >= grid->width || y < 0 || y >= grid->height) {
+        return 1;
+    }
+    return grid->cells[y * grid->width + x];
+}
+
+static void cave_grid_set(cave_grid* grid, i32 x, i32 y, u8 value) {
+    if (x < 0 || x >= grid->width || y < 0 || y >= grid->height) {
+        return;
+    }
+    grid->cells[y * grid->width + x] = value;
+}
+
+static i32 cave_grid_count_neighbors(const cave_grid* grid, i32 x, i32 y) {
+    i32 count = 0;
+    for (i32 dy = -1; dy <= 1; dy++) {
+        for (i32 dx = -1; dx <= 1; dx++) {
+            if (dx == 0 && dy == 0) continue;
+            if (cave_grid_get(grid, x + dx, y + dy)) {
+                count++;
+            }
+        }
+    }
+    return count;
+}
+
+static void calculate_texture_axes(const pxl8_vec3 normal, pxl8_vec3* u_axis, pxl8_vec3* v_axis) {
+    if (fabsf(normal.y) > 0.9f) {
+        *u_axis = (pxl8_vec3){1.0f, 0.0f, 0.0f};
+        *v_axis = (pxl8_vec3){0.0f, 0.0f, 1.0f};
+    } else if (fabsf(normal.x) > 0.7f) {
+        *u_axis = (pxl8_vec3){0.0f, 1.0f, 0.0f};
+        *v_axis = (pxl8_vec3){0.0f, 0.0f, 1.0f};
+    } else {
+        *u_axis = (pxl8_vec3){1.0f, 0.0f, 0.0f};
+        *v_axis = (pxl8_vec3){0.0f, 1.0f, 0.0f};
+    }
+}
+
+static void cave_grid_initialize(cave_grid* grid, f32 density) {
+    for (i32 y = 0; y < grid->height; y++) {
+        for (i32 x = 0; x < grid->width; x++) {
+            u8 value = (prng_float() < density) ? 1 : 0;
+            cave_grid_set(grid, x, y, value);
+        }
+    }
+}
+
+static void cave_grid_smooth(cave_grid* grid) {
+    cave_grid* temp = cave_grid_create(grid->width, grid->height);
+    if (!temp) return;
+
+    for (i32 y = 0; y < grid->height; y++) {
+        for (i32 x = 0; x < grid->width; x++) {
+            i32 neighbors = cave_grid_count_neighbors(grid, x, y);
+            u8 value = (neighbors > 4) ? 1 : 0;
+            cave_grid_set(temp, x, y, value);
+        }
+    }
+
+    memcpy(grid->cells, temp->cells, grid->width * grid->height);
+    cave_grid_destroy(temp);
+}
+
+static pxl8_result cave_to_bsp(pxl8_bsp* bsp, const cave_grid* grid) {
+    i32 vertex_count = 0;
+    i32 face_count = 0;
+    i32 floor_ceiling_count = 0;
+
+    for (i32 y = 0; y < grid->height; y++) {
+        for (i32 x = 0; x < grid->width; x++) {
+            if (cave_grid_get(grid, x, y) == 0) {
+                if (cave_grid_get(grid, x - 1, y) == 1) face_count++;
+                if (cave_grid_get(grid, x + 1, y) == 1) face_count++;
+                if (cave_grid_get(grid, x, y - 1) == 1) face_count++;
+                if (cave_grid_get(grid, x, y + 1) == 1) face_count++;
+                floor_ceiling_count++;
+            }
+        }
+    }
+
+    face_count += floor_ceiling_count * 2;
+    vertex_count = face_count * 4;
+
+    pxl8_debug("Cave generation: %dx%d grid -> %d faces, %d vertices",
+               grid->width, grid->height, face_count, vertex_count);
+
+    bsp->vertices = calloc(vertex_count, sizeof(pxl8_bsp_vertex));
+    bsp->faces = calloc(face_count, sizeof(pxl8_bsp_face));
+    bsp->planes = calloc(face_count, sizeof(pxl8_bsp_plane));
+    bsp->edges = calloc(vertex_count, sizeof(pxl8_bsp_edge));
+    bsp->surfedges = calloc(vertex_count, sizeof(i32));
+    bsp->texinfo = calloc(face_count, sizeof(pxl8_bsp_texinfo));
+
+    if (!bsp->vertices || !bsp->faces || !bsp->planes || !bsp->edges || !bsp->surfedges || !bsp->texinfo) {
+        return PXL8_ERROR_OUT_OF_MEMORY;
+    }
+
+    i32 vert_idx = 0;
+    i32 face_idx = 0;
+    i32 edge_idx = 0;
+
+    const f32 cell_size = 64.0f;
+    const f32 wall_height = 128.0f;
+
+    for (i32 y = 0; y < grid->height; y++) {
+        for (i32 x = 0; x < grid->width; x++) {
+            if (cave_grid_get(grid, x, y) == 0) {
+                f32 fx = (f32)x * cell_size;
+                f32 fy = (f32)y * cell_size;
+
+                if (cave_grid_get(grid, x - 1, y) == 1) {
+                    bsp->vertices[vert_idx + 0].position = (pxl8_vec3){fx, 0, fy};
+                    bsp->vertices[vert_idx + 1].position = (pxl8_vec3){fx, wall_height, fy};
+                    bsp->vertices[vert_idx + 2].position = (pxl8_vec3){fx, wall_height, fy + cell_size};
+                    bsp->vertices[vert_idx + 3].position = (pxl8_vec3){fx, 0, fy + cell_size};
+
+                    bsp->planes[face_idx].normal = (pxl8_vec3){-1, 0, 0};
+                    bsp->planes[face_idx].dist = -fx;
+
+                    bsp->faces[face_idx].plane_id = face_idx;
+                    bsp->faces[face_idx].num_edges = 4;
+                    bsp->faces[face_idx].first_edge = edge_idx;
+                    bsp->faces[face_idx].texinfo_id = face_idx;
+
+                    calculate_texture_axes(bsp->planes[face_idx].normal,
+                                          &bsp->texinfo[face_idx].u_axis,
+                                          &bsp->texinfo[face_idx].v_axis);
+                    bsp->texinfo[face_idx].u_offset = 0.0f;
+                    bsp->texinfo[face_idx].v_offset = 0.0f;
+
+                    for (i32 i = 0; i < 4; i++) {
+                        bsp->edges[edge_idx + i].vertex[0] = vert_idx + i;
+                        bsp->edges[edge_idx + i].vertex[1] = vert_idx + ((i + 1) % 4);
+                        bsp->surfedges[edge_idx + i] = edge_idx + i;
+                    }
+
+                    vert_idx += 4;
+                    edge_idx += 4;
+                    face_idx++;
+                }
+
+                if (cave_grid_get(grid, x + 1, y) == 1) {
+                    bsp->vertices[vert_idx + 0].position = (pxl8_vec3){fx + cell_size, 0, fy};
+                    bsp->vertices[vert_idx + 1].position = (pxl8_vec3){fx + cell_size, 0, fy + cell_size};
+                    bsp->vertices[vert_idx + 2].position = (pxl8_vec3){fx + cell_size, wall_height, fy + cell_size};
+                    bsp->vertices[vert_idx + 3].position = (pxl8_vec3){fx + cell_size, wall_height, fy};
+
+                    bsp->planes[face_idx].normal = (pxl8_vec3){1, 0, 0};
+                    bsp->planes[face_idx].dist = fx + cell_size;
+
+                    bsp->faces[face_idx].plane_id = face_idx;
+                    bsp->faces[face_idx].num_edges = 4;
+                    bsp->faces[face_idx].first_edge = edge_idx;
+                    bsp->faces[face_idx].texinfo_id = face_idx;
+
+                    calculate_texture_axes(bsp->planes[face_idx].normal,
+                                          &bsp->texinfo[face_idx].u_axis,
+                                          &bsp->texinfo[face_idx].v_axis);
+                    bsp->texinfo[face_idx].u_offset = 0.0f;
+                    bsp->texinfo[face_idx].v_offset = 0.0f;
+
+                    for (i32 i = 0; i < 4; i++) {
+                        bsp->edges[edge_idx + i].vertex[0] = vert_idx + i;
+                        bsp->edges[edge_idx + i].vertex[1] = vert_idx + ((i + 1) % 4);
+                        bsp->surfedges[edge_idx + i] = edge_idx + i;
+                    }
+
+                    vert_idx += 4;
+                    edge_idx += 4;
+                    face_idx++;
+                }
+
+                if (cave_grid_get(grid, x, y - 1) == 1) {
+                    bsp->vertices[vert_idx + 0].position = (pxl8_vec3){fx, 0, fy};
+                    bsp->vertices[vert_idx + 1].position = (pxl8_vec3){fx + cell_size, 0, fy};
+                    bsp->vertices[vert_idx + 2].position = (pxl8_vec3){fx + cell_size, wall_height, fy};
+                    bsp->vertices[vert_idx + 3].position = (pxl8_vec3){fx, wall_height, fy};
+
+                    bsp->planes[face_idx].normal = (pxl8_vec3){0, 0, -1};
+                    bsp->planes[face_idx].dist = -fy;
+
+                    bsp->faces[face_idx].plane_id = face_idx;
+                    bsp->faces[face_idx].num_edges = 4;
+                    bsp->faces[face_idx].first_edge = edge_idx;
+                    bsp->faces[face_idx].texinfo_id = face_idx;
+
+                    calculate_texture_axes(bsp->planes[face_idx].normal,
+                                          &bsp->texinfo[face_idx].u_axis,
+                                          &bsp->texinfo[face_idx].v_axis);
+                    bsp->texinfo[face_idx].u_offset = 0.0f;
+                    bsp->texinfo[face_idx].v_offset = 0.0f;
+
+                    for (i32 i = 0; i < 4; i++) {
+                        bsp->edges[edge_idx + i].vertex[0] = vert_idx + i;
+                        bsp->edges[edge_idx + i].vertex[1] = vert_idx + ((i + 1) % 4);
+                        bsp->surfedges[edge_idx + i] = edge_idx + i;
+                    }
+
+                    vert_idx += 4;
+                    edge_idx += 4;
+                    face_idx++;
+                }
+
+                if (cave_grid_get(grid, x, y + 1) == 1) {
+                    bsp->vertices[vert_idx + 0].position = (pxl8_vec3){fx, 0, fy + cell_size};
+                    bsp->vertices[vert_idx + 1].position = (pxl8_vec3){fx, wall_height, fy + cell_size};
+                    bsp->vertices[vert_idx + 2].position = (pxl8_vec3){fx + cell_size, wall_height, fy + cell_size};
+                    bsp->vertices[vert_idx + 3].position = (pxl8_vec3){fx + cell_size, 0, fy + cell_size};
+
+                    bsp->planes[face_idx].normal = (pxl8_vec3){0, 0, 1};
+                    bsp->planes[face_idx].dist = fy + cell_size;
+
+                    bsp->faces[face_idx].plane_id = face_idx;
+                    bsp->faces[face_idx].num_edges = 4;
+                    bsp->faces[face_idx].first_edge = edge_idx;
+                    bsp->faces[face_idx].texinfo_id = face_idx;
+
+                    calculate_texture_axes(bsp->planes[face_idx].normal,
+                                          &bsp->texinfo[face_idx].u_axis,
+                                          &bsp->texinfo[face_idx].v_axis);
+                    bsp->texinfo[face_idx].u_offset = 0.0f;
+                    bsp->texinfo[face_idx].v_offset = 0.0f;
+
+                    for (i32 i = 0; i < 4; i++) {
+                        bsp->edges[edge_idx + i].vertex[0] = vert_idx + i;
+                        bsp->edges[edge_idx + i].vertex[1] = vert_idx + ((i + 1) % 4);
+                        bsp->surfedges[edge_idx + i] = edge_idx + i;
+                    }
+
+                    vert_idx += 4;
+                    edge_idx += 4;
+                    face_idx++;
+                }
+            }
+        }
+    }
+
+    for (i32 y = 0; y < grid->height; y++) {
+        for (i32 x = 0; x < grid->width; x++) {
+            if (cave_grid_get(grid, x, y) == 0) {
+                f32 fx = (f32)x * cell_size;
+                f32 fy = (f32)y * cell_size;
+
+                bsp->vertices[vert_idx + 0].position = (pxl8_vec3){fx, 0, fy};
+                bsp->vertices[vert_idx + 1].position = (pxl8_vec3){fx, 0, fy + cell_size};
+                bsp->vertices[vert_idx + 2].position = (pxl8_vec3){fx + cell_size, 0, fy + cell_size};
+                bsp->vertices[vert_idx + 3].position = (pxl8_vec3){fx + cell_size, 0, fy};
+
+                bsp->planes[face_idx].normal = (pxl8_vec3){0, 1, 0};
+                bsp->planes[face_idx].dist = 0;
+
+                bsp->faces[face_idx].plane_id = face_idx;
+                bsp->faces[face_idx].num_edges = 4;
+                bsp->faces[face_idx].first_edge = edge_idx;
+                bsp->faces[face_idx].texinfo_id = face_idx;
+
+                calculate_texture_axes(bsp->planes[face_idx].normal,
+                                      &bsp->texinfo[face_idx].u_axis,
+                                      &bsp->texinfo[face_idx].v_axis);
+                bsp->texinfo[face_idx].u_offset = 0.0f;
+                bsp->texinfo[face_idx].v_offset = 0.0f;
+
+                for (i32 i = 0; i < 4; i++) {
+                    bsp->edges[edge_idx + i].vertex[0] = vert_idx + i;
+                    bsp->edges[edge_idx + i].vertex[1] = vert_idx + ((i + 1) % 4);
+                    bsp->surfedges[edge_idx + i] = edge_idx + i;
+                }
+
+                vert_idx += 4;
+                edge_idx += 4;
+                face_idx++;
+
+                bsp->vertices[vert_idx + 0].position = (pxl8_vec3){fx, wall_height, fy};
+                bsp->vertices[vert_idx + 1].position = (pxl8_vec3){fx + cell_size, wall_height, fy};
+                bsp->vertices[vert_idx + 2].position = (pxl8_vec3){fx + cell_size, wall_height, fy + cell_size};
+                bsp->vertices[vert_idx + 3].position = (pxl8_vec3){fx, wall_height, fy + cell_size};
+
+                bsp->planes[face_idx].normal = (pxl8_vec3){0, -1, 0};
+                bsp->planes[face_idx].dist = -wall_height;
+
+                bsp->faces[face_idx].plane_id = face_idx;
+                bsp->faces[face_idx].num_edges = 4;
+                bsp->faces[face_idx].first_edge = edge_idx;
+                bsp->faces[face_idx].texinfo_id = face_idx;
+
+                calculate_texture_axes(bsp->planes[face_idx].normal,
+                                      &bsp->texinfo[face_idx].u_axis,
+                                      &bsp->texinfo[face_idx].v_axis);
+                bsp->texinfo[face_idx].u_offset = 0.0f;
+                bsp->texinfo[face_idx].v_offset = 0.0f;
+
+                for (i32 i = 0; i < 4; i++) {
+                    bsp->edges[edge_idx + i].vertex[0] = vert_idx + i;
+                    bsp->edges[edge_idx + i].vertex[1] = vert_idx + ((i + 1) % 4);
+                    bsp->surfedges[edge_idx + i] = edge_idx + i;
+                }
+
+                vert_idx += 4;
+                edge_idx += 4;
+                face_idx++;
+            }
+        }
+    }
+
+    bsp->num_vertices = vertex_count;
+    bsp->num_faces = face_count;
+    bsp->num_planes = face_count;
+    bsp->num_edges = vertex_count;
+    bsp->num_surfedges = vertex_count;
+    bsp->num_texinfo = face_count;
+
+    bsp->leafs = calloc(1, sizeof(pxl8_bsp_leaf));
+    bsp->marksurfaces = calloc(face_count, sizeof(u16));
+
+    if (!bsp->leafs || !bsp->marksurfaces) {
+        return PXL8_ERROR_OUT_OF_MEMORY;
+    }
+
+    bsp->num_leafs = 1;
+    bsp->num_marksurfaces = face_count;
+
+    bsp->leafs[0].first_marksurface = 0;
+    bsp->leafs[0].num_marksurfaces = face_count;
+    bsp->leafs[0].contents = -2;
+
+    for (i32 i = 0; i < face_count; i++) {
+        bsp->marksurfaces[i] = i;
+    }
+
+    return PXL8_OK;
+}
+
+static pxl8_result procgen_cave(pxl8_bsp* bsp, const pxl8_procgen_params* params) {
+    prng_seed(params->seed);
+
+    cave_grid* grid = cave_grid_create(params->width, params->height);
+    if (!grid) {
+        return PXL8_ERROR_OUT_OF_MEMORY;
+    }
+
+    cave_grid_initialize(grid, params->density);
+
+    for (i32 i = 0; i < params->iterations; i++) {
+        cave_grid_smooth(grid);
+    }
+
+    pxl8_result result = cave_to_bsp(bsp, grid);
+    cave_grid_destroy(grid);
+
+    return result;
+}
+
+pxl8_result pxl8_procgen(pxl8_bsp* bsp, const pxl8_procgen_params* params) {
+    if (!bsp || !params) {
+        return PXL8_ERROR_NULL_POINTER;
+    }
+
+    switch (params->type) {
+        case PXL8_PROCGEN_CAVE:
+            return procgen_cave(bsp, params);
+
+        case PXL8_PROCGEN_DUNGEON:
+            pxl8_error("Dungeon generation not yet implemented");
+            return PXL8_ERROR_NOT_INITIALIZED;
+
+        case PXL8_PROCGEN_TERRAIN:
+            pxl8_error("Terrain generation not yet implemented");
+            return PXL8_ERROR_NOT_INITIALIZED;
+
+        default:
+            pxl8_error("Unknown procgen type: %d", params->type);
+            return PXL8_ERROR_INVALID_ARGUMENT;
+    }
+}
+
+void pxl8_procgen_tex(u8* buffer, const pxl8_procgen_tex_params* params) {
+    if (!buffer || !params) return;
+
+    prng_seed(params->seed);
+
+    u8 min_val = 255, max_val = 0;
+
+    for (i32 y = 0; y < params->height; y++) {
+        for (i32 x = 0; x < params->width; x++) {
+            i32 ix = (i32)((f32)x * params->scale);
+            i32 iy = (i32)((f32)y * params->scale);
+
+            u32 block_hash = (ix * 374761393 + iy * 668265263) ^ params->seed;
+            block_hash ^= block_hash >> 13;
+            block_hash ^= block_hash << 17;
+            block_hash ^= block_hash >> 5;
+
+            u32 pixel_hash = (x * 1597334677 + y * 3812015801) ^ params->seed;
+            pixel_hash ^= pixel_hash >> 13;
+            pixel_hash ^= pixel_hash << 17;
+            pixel_hash ^= pixel_hash >> 5;
+
+            u32 combined = (block_hash * 3 + pixel_hash) / 4;
+
+            u32 value_range = params->variation + 1;
+            i32 value = params->base_color + (combined % value_range);
+
+            if (value < 0) value = 0;
+            if (value > 15) value = 15;
+
+            u8 final_value = (u8)value;
+            buffer[y * params->width + x] = final_value;
+
+            if (final_value < min_val) min_val = final_value;
+            if (final_value > max_val) max_val = final_value;
+        }
+    }
+
+    pxl8_debug("Generated texture %dx%d: values range %u-%u (base=%u, variation=%u)",
+               params->width, params->height, min_val, max_val,
+               params->base_color, params->variation);
+}
diff --git a/src/pxl8_procgen.h b/src/pxl8_procgen.h
new file mode 100644
index 0000000..9ee1515
--- /dev/null
+++ b/src/pxl8_procgen.h
@@ -0,0 +1,56 @@
+#pragma once
+
+#include "pxl8_bsp.h"
+#include "pxl8_types.h"
+
+typedef enum pxl8_procgen_type {
+    PXL8_PROCGEN_CAVE,
+    PXL8_PROCGEN_DUNGEON,
+    PXL8_PROCGEN_TERRAIN
+} pxl8_procgen_type;
+
+typedef struct pxl8_procgen_params {
+    pxl8_procgen_type type;
+
+    i32 width;
+    i32 height;
+    i32 depth;
+    u32 seed;
+
+    f32 density;
+    i32 iterations;
+
+    void* type_params;
+} pxl8_procgen_params;
+
+typedef struct pxl8_procgen_cave_params {
+    i32 min_cave_size;
+} pxl8_procgen_cave_params;
+
+typedef struct pxl8_procgen_dungeon_params {
+    i32 room_count;
+    i32 min_room_size;
+    i32 max_room_size;
+    i32 corridor_width;
+} pxl8_procgen_dungeon_params;
+
+typedef struct pxl8_procgen_tex_params {
+    u32 seed;
+    i32 width;
+    i32 height;
+    f32 scale;
+    f32 roughness;
+    u8 base_color;
+    u8 variation;
+} pxl8_procgen_tex_params;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+pxl8_result pxl8_procgen(pxl8_bsp* bsp, const pxl8_procgen_params* params);
+void pxl8_procgen_tex(u8* buffer, const pxl8_procgen_tex_params* params);
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/src/pxl8_script.c b/src/pxl8_script.c
index 92d40e8..3192ea8 100644
--- a/src/pxl8_script.c
+++ b/src/pxl8_script.c
@@ -208,13 +208,31 @@ static const char* pxl8_ffi_cdefs =
 "pxl8_mat4 pxl8_mat4_scale(float x, float y, float z);\n"
 "pxl8_mat4 pxl8_mat4_translate(float x, float y, float z);\n"
 "\n"
+"typedef enum pxl8_procgen_type {\n"
+"    PXL8_PROCGEN_CAVE = 0,\n"
+"    PXL8_PROCGEN_DUNGEON = 1,\n"
+"    PXL8_PROCGEN_TERRAIN = 2\n"
+"} pxl8_procgen_type;\n"
+"\n"
+"typedef struct pxl8_procgen_params {\n"
+"    pxl8_procgen_type type;\n"
+"    int width;\n"
+"    int height;\n"
+"    int depth;\n"
+"    unsigned int seed;\n"
+"    float density;\n"
+"    int iterations;\n"
+"    void* type_params;\n"
+"} pxl8_procgen_params;\n"
+"\n"
 "typedef struct pxl8_world pxl8_world;\n"
 "pxl8_world* pxl8_world_create(void);\n"
 "void pxl8_world_destroy(pxl8_world* world);\n"
+"int pxl8_world_generate(pxl8_world* world, const pxl8_procgen_params* params);\n"
+"bool pxl8_world_is_loaded(const pxl8_world* world);\n"
 "int pxl8_world_load(pxl8_world* world, const char* path);\n"
 "void pxl8_world_render(pxl8_world* world, pxl8_gfx* gfx, pxl8_vec3 camera_pos);\n"
 "void pxl8_world_unload(pxl8_world* world);\n"
-"bool pxl8_world_is_loaded(const pxl8_world* world);\n"
 "\n"
 "typedef struct pxl8_ui pxl8_ui;\n"
 "typedef struct { unsigned char bg_color; unsigned int sprite_id; int corner_size; int edge_size; int padding; } pxl8_frame_theme;\n"
diff --git a/src/pxl8_sdl3.c b/src/pxl8_sdl3.c
index 4c0317a..6a72f23 100644
--- a/src/pxl8_sdl3.c
+++ b/src/pxl8_sdl3.c
@@ -294,9 +294,11 @@ SDL_AppResult SDL_AppEvent(void* appstate, SDL_Event* event) {
             break;
 
         case SDL_EVENT_KEY_DOWN: {
+#ifdef DEBUG
             if (event->key.key == SDLK_ESCAPE) {
                 game->running = false;
             }
+#endif
 
             SDL_Scancode scancode = event->key.scancode;
             if (scancode < 256) {
diff --git a/src/pxl8_world.c b/src/pxl8_world.c
index 7ccb9e5..dd0ca41 100644
--- a/src/pxl8_world.c
+++ b/src/pxl8_world.c
@@ -3,11 +3,13 @@
 
 #include "pxl8_bsp.h"
 #include "pxl8_macros.h"
+#include "pxl8_procgen.h"
 #include "pxl8_world.h"
 
 struct pxl8_world {
     pxl8_bsp bsp;
     bool loaded;
+    bool wireframe;
     u32 wireframe_color;
 };
 
@@ -34,6 +36,29 @@ void pxl8_world_destroy(pxl8_world* world) {
     free(world);
 }
 
+pxl8_result pxl8_world_generate(pxl8_world* world, const pxl8_procgen_params* params) {
+    if (!world || !params) return PXL8_ERROR_INVALID_ARGUMENT;
+
+    if (world->loaded) {
+        pxl8_bsp_destroy(&world->bsp);
+        world->loaded = false;
+    }
+
+    memset(&world->bsp, 0, sizeof(pxl8_bsp));
+
+    pxl8_result result = pxl8_procgen(&world->bsp, params);
+    if (result != PXL8_OK) {
+        pxl8_error("Failed to generate world");
+        pxl8_bsp_destroy(&world->bsp);
+        return result;
+    }
+
+    world->loaded = true;
+    pxl8_info("Generated world");
+
+    return PXL8_OK;
+}
+
 pxl8_result pxl8_world_load(pxl8_world* world, const char* path) {
     if (!world || !path) return PXL8_ERROR_INVALID_ARGUMENT;
 
@@ -59,7 +84,39 @@ pxl8_result pxl8_world_load(pxl8_world* world, const char* path) {
 void pxl8_world_render(pxl8_world* world, pxl8_gfx* gfx, pxl8_vec3 camera_pos) {
     if (!world || !gfx || !world->loaded) return;
 
-    pxl8_bsp_render_wireframe(gfx, &world->bsp, camera_pos, world->wireframe_color);
+    static bool texture_generated = false;
+    static u32 wall_texture_id = 0;
+    if (!texture_generated) {
+        u8 texture_data[64 * 64];
+
+        pxl8_procgen_tex_params tex_params = {
+            .seed = 12345,
+            .width = 64,
+            .height = 64,
+            .scale = 0.25f,
+            .roughness = 0.5f,
+            .base_color = 1,
+            .variation = 3
+        };
+
+        pxl8_procgen_tex(texture_data, &tex_params);
+
+        pxl8_result result = pxl8_gfx_create_texture(gfx, texture_data, 64, 64);
+        if (result >= 0) {
+            wall_texture_id = (u32)result;
+            pxl8_gfx_upload_atlas(gfx);
+            texture_generated = true;
+            pxl8_info("Generated stone texture with ID: %u", wall_texture_id);
+        } else {
+            pxl8_error("Failed to create wall texture: %d", result);
+        }
+    }
+
+    if (world->wireframe) {
+        pxl8_bsp_render_wireframe(gfx, &world->bsp, camera_pos, world->wireframe_color);
+    } else {
+        pxl8_bsp_render_solid(gfx, &world->bsp, camera_pos, wall_texture_id);
+    }
 }
 
 void pxl8_world_unload(pxl8_world* world) {
diff --git a/src/pxl8_world.h b/src/pxl8_world.h
index 3743be2..15289c1 100644
--- a/src/pxl8_world.h
+++ b/src/pxl8_world.h
@@ -2,6 +2,7 @@
 
 #include "pxl8_gfx.h"
 #include "pxl8_math.h"
+#include "pxl8_procgen.h"
 #include "pxl8_types.h"
 
 typedef struct pxl8_world pxl8_world;
@@ -13,12 +14,12 @@ extern "C" {
 pxl8_world* pxl8_world_create(void);
 void pxl8_world_destroy(pxl8_world* world);
 
+pxl8_result pxl8_world_generate(pxl8_world* world, const pxl8_procgen_params* params);
+bool pxl8_world_is_loaded(const pxl8_world* world);
 pxl8_result pxl8_world_load(pxl8_world* world, const char* path);
 void pxl8_world_render(pxl8_world* world, pxl8_gfx* gfx, pxl8_vec3 camera_pos);
 void pxl8_world_unload(pxl8_world* world);
 
-bool pxl8_world_is_loaded(const pxl8_world* world);
-
 #ifdef __cplusplus
 }
 #endif