wip: light probes + compute variant

demos/09-envmap.c

@@ -61,21 +61,29 @@ int main(int argc, char** argv) {
 
         static bool first_time = true;
         static bool animate_probe_pos = false;
+        static bool follow_cam = false;
         static vec3 probe_pos;
         if (input_down(KEY_T)) {
             animate_probe_pos = !animate_probe_pos;
         }
+        if (input_down(KEY_F)) {
+            follow_cam = !follow_cam;
+        }
         if (animate_probe_pos) {
             probe_pos = vec3(0, 5, 0);
             probe_pos.x = sinf(window_time()*2)*2.0f;
         }
-        if (input_down(KEY_SPACE) || first_time || animate_probe_pos) {
+        if (input_down(KEY_SPACE) || first_time || animate_probe_pos || follow_cam) {
             first_time = false;
             mat44 probe_proj, probe_view;
             if (!animate_probe_pos) {
                 probe_pos = cam.position;
             }
-            cubemap_bake_begin(&env_probe.cubemap, probe_pos, 1024, 1024);
+            if (follow_cam) {
+                probe_pos = cam.position;
+            }
+            unsigned tex_size = 256;
+            cubemap_bake_begin(&env_probe.cubemap, probe_pos, tex_size, tex_size);
             while (cubemap_bake_step(&env_probe.cubemap, probe_proj, probe_view)) {
                 skybox_render(&sky, probe_proj, probe_view);
                 shader_bind(mdl.program);

engine/art/shaders/cubemap_sh.glsl

@@ -0,0 +1,103 @@
+layout(local_size_x = 16, local_size_y = 16) in;
+
+uniform sampler2D inputTexture;
+layout(std430, binding = 1) buffer SHCoefficients {
+    vec3 sh[9];
+};
+layout(std430, binding = 2) buffer WorkGroupResults {
+    vec3 wg_results[];
+};
+
+uniform float skyIntensity;
+uniform ivec2 textureSize;
+uniform int faceIndex;
+uniform int pass;
+
+shared vec3 sh_local[9];
+
+const float PI = 3.14159265359;
+
+const vec3 skyDir[6] = vec3[6](
+    vec3( 1, 0, 0), vec3(-1, 0, 0),
+    vec3( 0, 1, 0), vec3( 0,-1, 0),
+    vec3( 0, 0, 1), vec3( 0, 0,-1)
+);
+const vec3 skyX[6] = vec3[6](
+    vec3( 0, 0,-1), vec3( 0, 0, 1),
+    vec3( 1, 0, 0), vec3( 1, 0, 0),
+    vec3( 1, 0, 0), vec3(-1, 0, 0)
+);
+const vec3 skyY[6] = vec3[6](
+    vec3( 0, 1, 0), vec3( 0, 1, 0),
+    vec3( 0, 0,-1), vec3( 0, 0, 1),
+    vec3( 0, 1, 0), vec3( 0, 1, 0)
+);
+
+void main() {
+    if (pass == 0) {
+        // First pass: process texels and accumulate in work groups
+        if (gl_LocalInvocationIndex == 0) {
+            for (int i = 0; i < 9; ++i) {
+                sh_local[i] = vec3(0.0);
+            }
+        }
+        barrier();
+
+        ivec2 texel = ivec2(gl_GlobalInvocationID.xy);
+        if (any(greaterThanEqual(texel, textureSize))) return;
+        
+        vec2 uv = (vec2(texel) + 0.5) / vec2(textureSize);
+        vec3 n = normalize(skyDir[faceIndex] +
+                           skyX[faceIndex] * (2.0 * uv.x - 1.0) +
+                           skyY[faceIndex] * (1.0 - 2.0 * uv.y));
+
+        vec3 color = textureLod(inputTexture, uv, 0).rgb;
+        float l = length(n);
+        vec3 light = color * (1.0 / (l * l * l)) * skyIntensity;
+
+        // Accumulate SH coefficients
+        vec3 sh_[9];
+        sh_[0] = light * 0.282095f;
+        sh_[1] = light * (-0.488603f * n.y * 2.0 / 3.0);
+        sh_[2] = light * (0.488603f * n.z * 2.0 / 3.0);
+        sh_[3] = light * (-0.488603f * n.x * 2.0 / 3.0);
+        sh_[4] = light * (1.092548f * n.x * n.y / 4.0);
+        sh_[5] = light * (-1.092548f * n.y * n.z / 4.0);
+        sh_[6] = light * (0.315392f * (3.0f * n.z * n.z - 1.0f) / 4.0);
+        sh_[7] = light * (-1.092548f * n.x * n.z / 4.0);
+        sh_[8] = light * (0.546274f * (n.x * n.x - n.y * n.y) / 4.0);
+        
+        // Add to local SH coefficients
+        for (int i = 0; i < 9; ++i) {
+            sh_local[i] += sh_[i];
+        }
+
+        barrier();
+
+        // Store work group results
+        if (gl_LocalInvocationIndex == 0) {
+            uint wg_index = gl_WorkGroupID.y * gl_NumWorkGroups.x + gl_WorkGroupID.x;
+            for (int i = 0; i < 9; ++i) {
+                wg_results[wg_index * 9 + i] = sh_local[i];
+            }
+        }
+    } else {
+        // Second pass: combine work group results
+        if (gl_WorkGroupID.x == 0 && gl_WorkGroupID.y == 0) {
+            vec3 total_sh[9] = vec3[9](vec3(0), vec3(0), vec3(0), vec3(0), vec3(0), vec3(0), vec3(0), vec3(0), vec3(0));
+            uint num_work_groups = gl_NumWorkGroups.x * gl_NumWorkGroups.y;
+            
+            for (uint i = gl_LocalInvocationIndex; i < num_work_groups; i += gl_WorkGroupSize.x * gl_WorkGroupSize.y) {
+                for (int j = 0; j < 9; ++j) {
+                    total_sh[j] += wg_results[i * 9 + j];
+                }
+            }
+            
+            barrier();
+            
+            if (gl_LocalInvocationIndex < 9) {
+                sh[gl_LocalInvocationIndex] += total_sh[gl_LocalInvocationIndex];
+            }
+        }
+    }
+}

engine/joint/v4k.h

@@ -383709,10 +383709,93 @@ void cubemap_bake_end(cubemap_t *c, float sky_intensity) {
         glDeleteTextures(1, &c->id);
         c->id = 0;
     }
+  
+    #if 0
+    static unsigned sh_shader = -1, sh_buffer = -1, wg_buffer = -1, u_intensity = -1, u_size = -1, u_face_index = -1, u_texture = -1, u_step = -1, u_pass = -1;
+    do_once {
+        sh_shader = compute(vfs_read("shaders/cubemap_sh.glsl"));
+        glGenBuffers(1, &sh_buffer);
+        glBindBuffer(GL_SHADER_STORAGE_BUFFER, sh_buffer);
+        glBufferData(GL_SHADER_STORAGE_BUFFER, 9 * sizeof(vec3), NULL, GL_DYNAMIC_COPY);
+        
+        u_texture = glGetUniformLocation(sh_shader, "cubeFace");
+        u_intensity = glGetUniformLocation(sh_shader, "skyIntensity");
+        u_size = glGetUniformLocation(sh_shader, "textureSize");
+        u_face_index = glGetUniformLocation(sh_shader, "faceIndex");
+        u_step = glGetUniformLocation(sh_shader, "step");
+        u_pass = glGetUniformLocation(sh_shader, "pass");
+    }
 
+    // Prepare work group buffer
+    glGenBuffers(1, &wg_buffer);
+    glBindBuffer(GL_SHADER_STORAGE_BUFFER, wg_buffer);
+    int num_work_groups = ((c->width + 15) / 16) * ((c->height + 15) / 16);
+    glBufferData(GL_SHADER_STORAGE_BUFFER, num_work_groups * 9 * sizeof(vec3), NULL, GL_DYNAMIC_COPY);
+    glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 2, wg_buffer);
+    
+    // Clear SH buffer
+    vec3 zero = vec3(0,0,0);
+    glBindBuffer(GL_SHADER_STORAGE_BUFFER, sh_buffer);
+    glClearBufferData(GL_SHADER_STORAGE_BUFFER, GL_RGB32F, GL_RGB, GL_FLOAT, &zero);
+    glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 1, sh_buffer);
+
+    // Set up render parameters
+    int step = 16;
+    shader_bind(sh_shader);
+    glUniform1f(u_intensity, sky_intensity);
+    glUniform2i(u_size, c->width, c->height);
+
+    for (int i = 0; i < 6; i++) {
+        // Bind texture to texture unit 0
+        glActiveTexture(GL_TEXTURE0);
+        glBindTexture(GL_TEXTURE_2D, c->textures[i]);
+        glUniform1i(u_texture, 0);
+
+        // Set up face index
+        glUniform1i(u_face_index, i);
+
+        // Dispatch compute shader
+        glUniform1i(u_pass, 0);
+        glDispatchCompute((c->width+step-1)/step, (c->height+step-1)/step, 1);
+        glMemoryBarrier(GL_SHADER_STORAGE_BARRIER_BIT);
+
+        glUniform1i(u_pass, 1);
+        glDispatchCompute((c->width+step-1)/step, (c->height+step-1)/step, 1);
+        glMemoryBarrier(GL_SHADER_STORAGE_BARRIER_BIT);
+    }
+
+    // Copy SH coefficients from buffer to array
+    glGetBufferSubData(GL_SHADER_STORAGE_BUFFER, 0, 9 * sizeof(vec3), c->sh);
+
+    // Normalize SH coefficients
+    int total_samples = 16 * 2 * 6;
+    for (int s = 0; s < 9; s++) {
+        c->sh[s] = scale3(c->sh[s], 32.f / total_samples);
+        // c->sh[s] = scale3(c->sh[s], 4.f * M_PI / total_samples);
+    }
+
+    glDeleteBuffers(1, &wg_buffer);
+
+    // Generate cubemap texture
     glGenTextures(1, &c->id);
     glBindTexture(GL_TEXTURE_CUBE_MAP, c->id);
-  
+
+    // Copy each face of the cubemap to the cubemap texture
+    for (int i = 0; i < 6; ++i) {
+        glCopyImageSubData(c->textures[i], GL_TEXTURE_2D, 0, 0, 0, 0,
+                           c->id, GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, 0, 0, 0,
+                           c->width, c->height, 1);
+    }
+    
+    // Generate mipmaps
+    glGenerateMipmap(GL_TEXTURE_CUBE_MAP);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
+    #else
+
     int samples = 0;
     for (int i = 0; i < 6; i++) {
         glBindFramebuffer(GL_FRAMEBUFFER, c->framebuffers[i]);
@@ -383755,6 +383838,9 @@ void cubemap_bake_end(cubemap_t *c, float sky_intensity) {
     for (int s = 0; s < 9; s++) {
         c->sh[s] = scale3(c->sh[s], 32.f / samples);
     }
+    
+    glGenTextures(1, &c->id);
+    glBindTexture(GL_TEXTURE_CUBE_MAP, c->id);
 
     glGenerateMipmap(GL_TEXTURE_CUBE_MAP);
     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
@@ -383762,6 +383848,7 @@ void cubemap_bake_end(cubemap_t *c, float sky_intensity) {
     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
+    #endif
 
     glBindFramebuffer(GL_FRAMEBUFFER, sky_last_fb);
     glViewport(sky_last_vp[0], sky_last_vp[1], sky_last_vp[2], sky_last_vp[3]);

engine/split/v4k_render.c

@@ -2025,10 +2025,93 @@ void cubemap_bake_end(cubemap_t *c, float sky_intensity) {
         glDeleteTextures(1, &c->id);
         c->id = 0;
     }
+  
+    #if 0
+    static unsigned sh_shader = -1, sh_buffer = -1, wg_buffer = -1, u_intensity = -1, u_size = -1, u_face_index = -1, u_texture = -1, u_step = -1, u_pass = -1;
+    do_once {
+        sh_shader = compute(vfs_read("shaders/cubemap_sh.glsl"));
+        glGenBuffers(1, &sh_buffer);
+        glBindBuffer(GL_SHADER_STORAGE_BUFFER, sh_buffer);
+        glBufferData(GL_SHADER_STORAGE_BUFFER, 9 * sizeof(vec3), NULL, GL_DYNAMIC_COPY);
+        
+        u_texture = glGetUniformLocation(sh_shader, "cubeFace");
+        u_intensity = glGetUniformLocation(sh_shader, "skyIntensity");
+        u_size = glGetUniformLocation(sh_shader, "textureSize");
+        u_face_index = glGetUniformLocation(sh_shader, "faceIndex");
+        u_step = glGetUniformLocation(sh_shader, "step");
+        u_pass = glGetUniformLocation(sh_shader, "pass");
+    }
 
+    // Prepare work group buffer
+    glGenBuffers(1, &wg_buffer);
+    glBindBuffer(GL_SHADER_STORAGE_BUFFER, wg_buffer);
+    int num_work_groups = ((c->width + 15) / 16) * ((c->height + 15) / 16);
+    glBufferData(GL_SHADER_STORAGE_BUFFER, num_work_groups * 9 * sizeof(vec3), NULL, GL_DYNAMIC_COPY);
+    glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 2, wg_buffer);
+    
+    // Clear SH buffer
+    vec3 zero = vec3(0,0,0);
+    glBindBuffer(GL_SHADER_STORAGE_BUFFER, sh_buffer);
+    glClearBufferData(GL_SHADER_STORAGE_BUFFER, GL_RGB32F, GL_RGB, GL_FLOAT, &zero);
+    glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 1, sh_buffer);
+
+    // Set up render parameters
+    int step = 16;
+    shader_bind(sh_shader);
+    glUniform1f(u_intensity, sky_intensity);
+    glUniform2i(u_size, c->width, c->height);
+
+    for (int i = 0; i < 6; i++) {
+        // Bind texture to texture unit 0
+        glActiveTexture(GL_TEXTURE0);
+        glBindTexture(GL_TEXTURE_2D, c->textures[i]);
+        glUniform1i(u_texture, 0);
+
+        // Set up face index
+        glUniform1i(u_face_index, i);
+
+        // Dispatch compute shader
+        glUniform1i(u_pass, 0);
+        glDispatchCompute((c->width+step-1)/step, (c->height+step-1)/step, 1);
+        glMemoryBarrier(GL_SHADER_STORAGE_BARRIER_BIT);
+
+        glUniform1i(u_pass, 1);
+        glDispatchCompute((c->width+step-1)/step, (c->height+step-1)/step, 1);
+        glMemoryBarrier(GL_SHADER_STORAGE_BARRIER_BIT);
+    }
+
+    // Copy SH coefficients from buffer to array
+    glGetBufferSubData(GL_SHADER_STORAGE_BUFFER, 0, 9 * sizeof(vec3), c->sh);
+
+    // Normalize SH coefficients
+    int total_samples = 16 * 2 * 6;
+    for (int s = 0; s < 9; s++) {
+        c->sh[s] = scale3(c->sh[s], 32.f / total_samples);
+        // c->sh[s] = scale3(c->sh[s], 4.f * M_PI / total_samples);
+    }
+
+    glDeleteBuffers(1, &wg_buffer);
+
+    // Generate cubemap texture
     glGenTextures(1, &c->id);
     glBindTexture(GL_TEXTURE_CUBE_MAP, c->id);
-  
+
+    // Copy each face of the cubemap to the cubemap texture
+    for (int i = 0; i < 6; ++i) {
+        glCopyImageSubData(c->textures[i], GL_TEXTURE_2D, 0, 0, 0, 0,
+                           c->id, GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, 0, 0, 0,
+                           c->width, c->height, 1);
+    }
+    
+    // Generate mipmaps
+    glGenerateMipmap(GL_TEXTURE_CUBE_MAP);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
+    #else
+
     int samples = 0;
     for (int i = 0; i < 6; i++) {
         glBindFramebuffer(GL_FRAMEBUFFER, c->framebuffers[i]);
@@ -2071,6 +2154,9 @@ void cubemap_bake_end(cubemap_t *c, float sky_intensity) {
     for (int s = 0; s < 9; s++) {
         c->sh[s] = scale3(c->sh[s], 32.f / samples);
     }
+    
+    glGenTextures(1, &c->id);
+    glBindTexture(GL_TEXTURE_CUBE_MAP, c->id);
 
     glGenerateMipmap(GL_TEXTURE_CUBE_MAP);
     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
@@ -2078,6 +2164,7 @@ void cubemap_bake_end(cubemap_t *c, float sky_intensity) {
     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
+    #endif
 
     glBindFramebuffer(GL_FRAMEBUFFER, sky_last_fb);
     glViewport(sky_last_vp[0], sky_last_vp[1], sky_last_vp[2], sky_last_vp[3]);

engine/v4k.c

@@ -18824,10 +18824,93 @@ void cubemap_bake_end(cubemap_t *c, float sky_intensity) {
         glDeleteTextures(1, &c->id);
         c->id = 0;
     }
+  
+    #if 0
+    static unsigned sh_shader = -1, sh_buffer = -1, wg_buffer = -1, u_intensity = -1, u_size = -1, u_face_index = -1, u_texture = -1, u_step = -1, u_pass = -1;
+    do_once {
+        sh_shader = compute(vfs_read("shaders/cubemap_sh.glsl"));
+        glGenBuffers(1, &sh_buffer);
+        glBindBuffer(GL_SHADER_STORAGE_BUFFER, sh_buffer);
+        glBufferData(GL_SHADER_STORAGE_BUFFER, 9 * sizeof(vec3), NULL, GL_DYNAMIC_COPY);
+        
+        u_texture = glGetUniformLocation(sh_shader, "cubeFace");
+        u_intensity = glGetUniformLocation(sh_shader, "skyIntensity");
+        u_size = glGetUniformLocation(sh_shader, "textureSize");
+        u_face_index = glGetUniformLocation(sh_shader, "faceIndex");
+        u_step = glGetUniformLocation(sh_shader, "step");
+        u_pass = glGetUniformLocation(sh_shader, "pass");
+    }
 
+    // Prepare work group buffer
+    glGenBuffers(1, &wg_buffer);
+    glBindBuffer(GL_SHADER_STORAGE_BUFFER, wg_buffer);
+    int num_work_groups = ((c->width + 15) / 16) * ((c->height + 15) / 16);
+    glBufferData(GL_SHADER_STORAGE_BUFFER, num_work_groups * 9 * sizeof(vec3), NULL, GL_DYNAMIC_COPY);
+    glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 2, wg_buffer);
+    
+    // Clear SH buffer
+    vec3 zero = vec3(0,0,0);
+    glBindBuffer(GL_SHADER_STORAGE_BUFFER, sh_buffer);
+    glClearBufferData(GL_SHADER_STORAGE_BUFFER, GL_RGB32F, GL_RGB, GL_FLOAT, &zero);
+    glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 1, sh_buffer);
+
+    // Set up render parameters
+    int step = 16;
+    shader_bind(sh_shader);
+    glUniform1f(u_intensity, sky_intensity);
+    glUniform2i(u_size, c->width, c->height);
+
+    for (int i = 0; i < 6; i++) {
+        // Bind texture to texture unit 0
+        glActiveTexture(GL_TEXTURE0);
+        glBindTexture(GL_TEXTURE_2D, c->textures[i]);
+        glUniform1i(u_texture, 0);
+
+        // Set up face index
+        glUniform1i(u_face_index, i);
+
+        // Dispatch compute shader
+        glUniform1i(u_pass, 0);
+        glDispatchCompute((c->width+step-1)/step, (c->height+step-1)/step, 1);
+        glMemoryBarrier(GL_SHADER_STORAGE_BARRIER_BIT);
+
+        glUniform1i(u_pass, 1);
+        glDispatchCompute((c->width+step-1)/step, (c->height+step-1)/step, 1);
+        glMemoryBarrier(GL_SHADER_STORAGE_BARRIER_BIT);
+    }
+
+    // Copy SH coefficients from buffer to array
+    glGetBufferSubData(GL_SHADER_STORAGE_BUFFER, 0, 9 * sizeof(vec3), c->sh);
+
+    // Normalize SH coefficients
+    int total_samples = 16 * 2 * 6;
+    for (int s = 0; s < 9; s++) {
+        c->sh[s] = scale3(c->sh[s], 32.f / total_samples);
+        // c->sh[s] = scale3(c->sh[s], 4.f * M_PI / total_samples);
+    }
+
+    glDeleteBuffers(1, &wg_buffer);
+
+    // Generate cubemap texture
     glGenTextures(1, &c->id);
     glBindTexture(GL_TEXTURE_CUBE_MAP, c->id);
-  
+
+    // Copy each face of the cubemap to the cubemap texture
+    for (int i = 0; i < 6; ++i) {
+        glCopyImageSubData(c->textures[i], GL_TEXTURE_2D, 0, 0, 0, 0,
+                           c->id, GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, 0, 0, 0,
+                           c->width, c->height, 1);
+    }
+    
+    // Generate mipmaps
+    glGenerateMipmap(GL_TEXTURE_CUBE_MAP);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
+    #else
+
     int samples = 0;
     for (int i = 0; i < 6; i++) {
         glBindFramebuffer(GL_FRAMEBUFFER, c->framebuffers[i]);
@@ -18870,6 +18953,9 @@ void cubemap_bake_end(cubemap_t *c, float sky_intensity) {
     for (int s = 0; s < 9; s++) {
         c->sh[s] = scale3(c->sh[s], 32.f / samples);
     }
+    
+    glGenTextures(1, &c->id);
+    glBindTexture(GL_TEXTURE_CUBE_MAP, c->id);
 
     glGenerateMipmap(GL_TEXTURE_CUBE_MAP);
     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
@@ -18877,6 +18963,7 @@ void cubemap_bake_end(cubemap_t *c, float sky_intensity) {
     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
     glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
+    #endif
 
     glBindFramebuffer(GL_FRAMEBUFFER, sky_last_fb);
     glViewport(sky_last_vp[0], sky_last_vp[1], sky_last_vp[2], sky_last_vp[3]);