Merge pull request 'Skybox Implementation' (#1) from feature/skybox into main

Reviewed-on: #1

main.c

@@ -6,6 +6,7 @@
 #include "stdlib.h"
 #include "stdint.h"
 #include "time.h"
+#include "rlgl.h"
 
 //----------------------------------------------------------------------------------
 // Defines and Macros
@@ -214,6 +215,49 @@ int main(void)
     int locCutoff = GetShaderLocation(shAlphaClip, "u_alphaCutoff");
     float cutoff = 0.3f; // tweak to taste; 0.3 - 0.5 works well for tree PNGs
     SetShaderValue(shAlphaClip, locCutoff, &cutoff, SHADER_UNIFORM_FLOAT);    
+
+
+
+    // --- Skybox setup ---
+    // Generate cube mesh
+    Mesh cube = GenMeshCube(1.0f, 1.0f, 1.0f);
+    Model skybox = LoadModelFromMesh(cube);
+
+    // Load skybox shader
+    // Make sure the .vs/.fs are in your resources/shaders/glsl330/ folder
+    Shader skyboxShader = LoadShader(
+        "resources/shaders/skybox.vs",
+        "resources/shaders/skybox.fs"
+    );
+
+    // Attach shader to skybox
+    skybox.materials[0].shader = skyboxShader;
+
+    // Load your cubemap (cross layout image)
+    Image img = LoadImage("resources/cubemap/cubemap.png");
+    // AUTO_DETECT will figure out layout (works for cross 4x3, panorama, etc.)
+    skybox.materials[0].maps[MATERIAL_MAP_CUBEMAP].texture = 
+        LoadTextureCubemap(img, CUBEMAP_LAYOUT_AUTO_DETECT);
+    UnloadImage(img);
+
+    // Tell the shader which material map is the environmentMap
+    int mapType = MATERIAL_MAP_CUBEMAP;
+    SetShaderValue(skyboxShader, 
+        GetShaderLocation(skyboxShader, "environmentMap"), 
+        &mapType, SHADER_UNIFORM_INT);
+
+    // Flip/gamma options (set to 0 for PNG cross)
+    int vflipped = 0;
+    int doGamma  = 0;
+    SetShaderValue(skyboxShader, GetShaderLocation(skyboxShader, "vflipped"), &vflipped, SHADER_UNIFORM_INT);
+    SetShaderValue(skyboxShader, GetShaderLocation(skyboxShader, "doGamma"),  &doGamma,  SHADER_UNIFORM_INT);
+
+    // Done – now you can draw it
+
+
+
+
+
     //--------------------------------------------------------------------------------------
 
     // Main game loop
@@ -333,6 +377,22 @@ int main(void)
                     ClearBackground(BLACK);
 
                     BeginMode3D(g.player.camera);
+
+                        rlDisableBackfaceCulling();
+                        rlDisableDepthMask();
+
+                        // keep it centered on the camera
+                        skybox.transform = MatrixTranslate(
+                            g.player.camera.position.x,
+                            g.player.camera.position.y,
+                            g.player.camera.position.z
+                        );
+
+                        DrawModel(skybox, (Vector3){0}, 1.0f, WHITE);
+
+                        rlEnableDepthMask();
+                        rlEnableBackfaceCulling();
+
                         DrawLevel(mdlTile);
 
                         BeginShaderMode(shAlphaClip);

resources/shaders/skybox.fs

@@ -0,0 +1,30 @@
+#version 330
+
+// Input vertex attributes (from vertex shader)
+in vec3 fragPosition;
+
+// Input uniform values
+uniform samplerCube environmentMap;
+uniform bool vflipped;
+uniform bool doGamma;
+
+// Output fragment color
+out vec4 finalColor;
+
+void main()
+{
+    // Fetch color from texture map
+    vec3 color = vec3(0.0);
+
+    if (vflipped) color = texture(environmentMap, vec3(fragPosition.x, -fragPosition.y, fragPosition.z)).rgb;
+    else color = texture(environmentMap, fragPosition).rgb;
+
+    if (doGamma)// Apply gamma correction
+    {
+        color = color/(color + vec3(1.0));
+        color = pow(color, vec3(1.0/2.2));
+    }
+
+    // Calculate final fragment color
+    finalColor = vec4(color, 1.0);
+}

resources/shaders/skybox.vs

@@ -0,0 +1,24 @@
+#version 330
+
+// Input vertex attributes
+in vec3 vertexPosition;
+
+// Input uniform values
+uniform mat4 matProjection;
+uniform mat4 matView;
+
+// Output vertex attributes (to fragment shader)
+out vec3 fragPosition;
+
+void main()
+{
+    // Calculate fragment position based on model transformations
+    fragPosition = vertexPosition;
+
+    // Remove translation from the view matrix
+    mat4 rotView = mat4(mat3(matView));
+    vec4 clipPos = matProjection*rotView*vec4(vertexPosition, 1.0);
+
+    // Calculate final vertex position
+    gl_Position = clipPos;
+}