Fix EXTERNAL_CONFIG_FLAGS being defined even when no custom config is used when building with zig (#5410)

This improvement is just a prove of concept, at this moment `PLATFORM_WEB` is limited in terms of software rendering by `GLFW` that only allows creating a WebGL canvas context with `glfwCreateWindow()`.

We can skip that call but then some GLFW functionality is not available (windowing, inputs). The best solution is replacing GLFW completely by a pure Emscripten implementation for `PLATFORM_WEB`.

build.zig

@@ -155,9 +155,9 @@ fn compileRaylib(b: *std.Build, target: std.Build.ResolvedTarget, optimize: std.
         );
     }
 
-    // Sets a flag indicating the use of a custom `config.h`
-    try raylib_flags_arr.append(b.allocator, "-DEXTERNAL_CONFIG_FLAGS");
     if (options.config.len > 0) {
+        // Sets a flag indicating the use of a custom `config.h`
+        try raylib_flags_arr.append(b.allocator, "-DEXTERNAL_CONFIG_FLAGS");
         // Splits a space-separated list of config flags into multiple flags
         //
         // Note: This means certain flags like `-x c++` won't be processed properly.

src/external/rlsw.h

@@ -2217,7 +2217,7 @@ static inline bool sw_triangle_face_culling(void)
     const float *h2 = RLSW.vertexBuffer[2].homogeneous;
 
     // Compute a value proportional to the signed area in the projected 2D plane,
-    // calculated directly using homogeneous coordinates BEFORE division by w.
+    // calculated directly using homogeneous coordinates BEFORE division by w
     // This is the determinant of the matrix formed by the (x, y, w) components
     // of the vertices, which correctly captures the winding order in homogeneous
     // space and its relationship to the projected 2D winding order, even with
@@ -2235,13 +2235,13 @@ static inline bool sw_triangle_face_culling(void)
     // Discard the triangle if its winding order (determined by the sign
     // of the homogeneous area/determinant) matches the culled direction
     // A positive hSgnArea typically corresponds to a counter-clockwise
-    // winding in the projected space when all w > 0.
+    // winding in the projected space when all w > 0
     // This test is robust for points with w > 0 or w < 0, correctly
     // capturing the change in orientation when crossing the w=0 plane
 
     // The culling logic remains the same based on the signed area/determinant
     // A value of 0 for hSgnArea means the points are collinear in (x, y, w)
-    // space, which corresponds to a degenerate triangle projection.
+    // space, which corresponds to a degenerate triangle projection
     // Such triangles are typically not culled by this test (0 < 0 is false, 0 > 0 is false)
     // and should be handled by the clipper if necessary
     return (RLSW.cullFace == SW_FRONT)? (hSgnArea < 0) : (hSgnArea > 0); // Cull if winding is "clockwise" : "counter-clockwise"
@@ -2602,7 +2602,7 @@ static inline bool sw_quad_face_culling(void)
     // space, which corresponds to a degenerate triangle projection
     // Such quads might also be degenerate or non-planar. They are typically
     // not culled by this test (0 < 0 is false, 0 > 0 is false)
-    // and should be handled by the clipper if necessary.
+    // and should be handled by the clipper if necessary
 
     return (RLSW.cullFace == SW_FRONT)? (hSgnArea < 0.0f) : (hSgnArea > 0.0f); // Cull if winding is "clockwise" : "counter-clockwise"
 }

src/platforms/rcore_desktop_glfw.c

@@ -894,7 +894,8 @@ Vector2 GetMonitorPosition(int monitor)
 
     if ((monitor >= 0) && (monitor < monitorCount))
     {
-        int x, y;
+        int x = 0; 
+        int y = 0;
         glfwGetMonitorPos(monitors[monitor], &x, &y);
 
         return (Vector2){ (float)x, (float)y };

src/platforms/rcore_memory.c

@@ -428,7 +428,7 @@ void SetMouseCursor(int cursor)
     TRACELOG(LOG_WARNING, "SetMouseCursor() not implemented on target platform");
 }
 
-// Get physical key name.
+// Get physical key name
 const char *GetKeyName(int key)
 {
     TRACELOG(LOG_WARNING, "GetKeyName() not implemented on target platform");

src/platforms/rcore_web.c

@@ -78,6 +78,11 @@ typedef struct {
     int unmaximizedHeight;              // Internal var to store the unmaximized window (canvas) height
     
     char canvasId[64];                  // Keep current canvas id where wasm app is running
+                                        // NOTE: Useful when trying to run multiple wasms in different canvases in same webpage
+    
+#if defined(GRAPHICS_API_OPENGL_11_SOFTWARE)
+    unsigned int *pixels;               // Pointer to pixel data buffer (RGBA 32bit format)
+#endif
 } PlatformData;
 
 //----------------------------------------------------------------------------------
@@ -264,7 +269,8 @@ void ToggleFullscreen(void)
             };
             emscripten_enter_soft_fullscreen(platform.canvasId, &strategy);
 
-            int width, height;
+            int width = 0;
+            int height = 0;
             emscripten_get_canvas_element_size(platform.canvasId, &width, &height);
             TRACELOG(LOG_WARNING, "Emscripten: Enter fullscreen: Canvas size: %i x %i", width, height);
 
@@ -883,7 +889,32 @@ void DisableCursor(void)
 // Swap back buffer with front buffer (screen drawing)
 void SwapScreenBuffer(void)
 {
+#if defined(GRAPHICS_API_OPENGL_11_SOFTWARE)
+    // Update framebuffer
+    rlCopyFramebuffer(0, 0, CORE.Window.render.width, CORE.Window.render.height, PIXELFORMAT_UNCOMPRESSED_R8G8B8A8, platform.pixels);
+    
+    // Copy framebuffer data into canvas
+    EM_ASM({
+        const width = $0;
+        const height = $1;
+        const ptr = $2;
+
+        // Get canvas and 2d context created
+        const canvas = Module.canvas;
+        const ctx = canvas.getContext('2d');
+
+        if (!Module.__img || (Module.__img.width !== width) || (Module.__img.height !== height)) {
+            Module.__img = ctx.createImageData(width, height);
+        }
+
+        const src = HEAPU8.subarray(ptr, ptr + width*height*4); // RGBA (4 bytes)
+        Module.__img.data.set(src);
+        ctx.putImageData(Module.__img, 0, 0);
+
+    }, CORE.Window.screen.width, CORE.Window.screen.height, platform.pixels);
+#else
     glfwSwapBuffers(platform.handle);
+#endif
 }
 
 //----------------------------------------------------------------------------------
@@ -974,7 +1005,7 @@ void SetMouseCursor(int cursor)
     }
 }
 
-// Get physical key name.
+// Get physical key name
 const char *GetKeyName(int key)
 {
     TRACELOG(LOG_WARNING, "GetKeyName() not implemented on target platform");
@@ -1214,7 +1245,21 @@ int InitPlatform(void)
 
     // Init fullscreen toggle required var:
     platform.ourFullscreen = false;
-
+    
+#if defined(GRAPHICS_API_OPENGL_11_SOFTWARE)
+    // Avoid creating a WebGL canvas, avoid calling glfwCreateWindow()
+    emscripten_set_canvas_element_size(platform.canvasId, CORE.Window.screen.width, CORE.Window.screen.height);
+    EM_ASM({
+        const canvas = document.getElementById("canvas");
+        Module.canvas = canvas;
+    });
+    
+    // Load memory framebuffer with desired screen size
+    // NOTE: Despite using a software framebuffer for blitting, GLFW still creates a WebGL canvas,
+    // but it is not being used, on SwapScreenBuffer() the pure software renderer is used
+    // TODO: Consider requesting another type of canvas, not a WebGL one --> Replace GLFW-web by Emscripten?
+    platform.pixels = (unsigned int *)RL_CALLOC(CORE.Window.screen.width*CORE.Window.screen.height, sizeof(unsigned int));
+#else
     if (CORE.Window.fullscreen)
     {
         // remember center for switchinging from fullscreen to window
@@ -1289,6 +1334,7 @@ int InitPlatform(void)
         TRACELOG(LOG_WARNING, "GLFW: Failed to initialize Window");
         return -1;
     }
+#endif
 
     // WARNING: glfwCreateWindow() title doesn't work with emscripten
     emscripten_set_window_title((CORE.Window.title != 0)? CORE.Window.title : " ");

src/rcore.c

@@ -117,7 +117,7 @@
 #include <time.h>                   // Required for: time() [Used in InitTimer()]
 #include <math.h>                   // Required for: tan() [Used in BeginMode3D()], atan2f() [Used in LoadVrStereoConfig()]
 
-#if defined(PLATFORM_MEMORY)
+#if defined(PLATFORM_MEMORY) || defined(PLATFORM_WEB)
     #define SW_GL_FRAMEBUFFER_COPY_BGRA false
 #endif
 #define RLGL_IMPLEMENTATION

src/rmodels.c

@@ -3655,7 +3655,7 @@ void GenMeshTangents(Mesh *mesh)
     for (int t = 0; t < mesh->triangleCount; t++)
     {
         // Get triangle vertex indices
-        int i0, i1, i2;
+        int i0 = 0, i1 = 0, i2 = 0;
 
         if (mesh->indices != NULL)
         {
@@ -4150,7 +4150,9 @@ RayCollision GetRayCollisionMesh(Ray ray, Mesh mesh, Matrix transform)
         // Test against all triangles in mesh
         for (int i = 0; i < triangleCount; i++)
         {
-            Vector3 a, b, c;
+            Vector3 a = { 0 }; 
+            Vector3 b = { 0 };
+            Vector3 c = { 0 };
             Vector3 *vertdata = (Vector3 *)mesh.vertices;
 
             if (mesh.indices)
@@ -4193,8 +4195,10 @@ RayCollision GetRayCollisionTriangle(Ray ray, Vector3 p1, Vector3 p2, Vector3 p3
     RayCollision collision = { 0 };
     Vector3 edge1 = { 0 };
     Vector3 edge2 = { 0 };
-    Vector3 p, q, tv;
-    float det, invDet, u, v, t;
+    Vector3 p = { 0 };
+    Vector3 q = { 0 };
+    Vector3 tv = { 0 };
+    float det = 0.0f, invDet = 0.0f, u = 0.0f, v = 0.0f, t = 0.0f;
 
     // Find vectors for two edges sharing V1
     edge1 = Vector3Subtract(p2, p1);

src/rtext.c

@@ -649,7 +649,9 @@ GlyphInfo *LoadFontData(const unsigned char *fileData, int dataSize, int fontSiz
 
             // Calculate font basic metrics
             // NOTE: ascent is equivalent to font baseline
-            int ascent, descent, lineGap;
+            int ascent = 0;
+            int descent = 0;
+            int lineGap = 0;
             stbtt_GetFontVMetrics(&fontInfo, &ascent, &descent, &lineGap);
 
             // In case no chars count provided, default to 95
@@ -2483,7 +2485,15 @@ static Font LoadBMFont(const char *fileName)
     font.glyphs = (GlyphInfo *)RL_MALLOC(glyphCount*sizeof(GlyphInfo));
     font.recs = (Rectangle *)RL_MALLOC(glyphCount*sizeof(Rectangle));
 
-    int charId, charX, charY, charWidth, charHeight, charOffsetX, charOffsetY, charAdvanceX, pageID;
+    int charId = 0;
+    int charX = 0;
+    int charY = 0;
+    int charWidth = 0; 
+    int charHeight = 0;
+    int charOffsetX = 0;
+    int charOffsetY = 0;
+    int charAdvanceX = 0;
+    int pageID = 0;
 
     for (int i = 0; i < glyphCount; i++)
     {

src/rtextures.c

@@ -1727,7 +1727,8 @@ void ImageResizeNN(Image *image, int newWidth, int newHeight)
     int xRatio = (int)((image->width << 16)/newWidth) + 1;
     int yRatio = (int)((image->height << 16)/newHeight) + 1;
 
-    int x2, y2;
+    int x2 = 0;
+    int y2 = 0;
     for (int y = 0; y < newHeight; y++)
     {
         for (int x = 0; x < newWidth; x++)
@@ -2488,8 +2489,13 @@ void ImageDither(Image *image, int rBpp, int gBpp, int bBpp, int aBpp)
         Color oldPixel = WHITE;
         Color newPixel = WHITE;
 
-        int rError, gError, bError;
-        unsigned short rPixel, gPixel, bPixel, aPixel;   // Used for 16bit pixel composition
+        int rError = 0;
+        int gError = 0;
+        int bError = 0;
+        unsigned short rPixel = 0;   // Used for 16bit pixel composition
+        unsigned short gPixel = 0;
+        unsigned short bPixel = 0;
+        unsigned short aPixel = 0;
 
         #define MIN(a,b) (((a)<(b))?(a):(b))
 
@@ -4006,7 +4012,9 @@ void ImageDraw(Image *dst, Image src, Rectangle srcRec, Rectangle dstRec, Color
         //    [-] GetPixelColor(): Get Vector4 instead of Color, easier for ColorAlphaBlend()
         //    [ ] TODO: Support 16bit and 32bit (float) channels drawing
 
-        Color colSrc, colDst, blend;
+        Color colSrc = { 0 };
+        Color colDst = { 0 };
+        Color blend = { 0 };
         bool blendRequired = true;
 
         // Fast path: Avoid blend if source has no alpha to blend
@@ -4681,17 +4689,23 @@ void DrawTextureNPatch(Texture2D texture, NPatchInfo nPatchInfo, Rectangle dest,
             bottomBorder = patchHeight - topBorder;
         }
 
-        Vector2 vertA, vertB, vertC, vertD;
-        vertA.x = 0.0f;                             // outer left
-        vertA.y = 0.0f;                             // outer top
-        vertB.x = leftBorder;                       // inner left
-        vertB.y = topBorder;                        // inner top
-        vertC.x = patchWidth  - rightBorder;        // inner right
-        vertC.y = patchHeight - bottomBorder;       // inner bottom
-        vertD.x = patchWidth;                       // outer right
-        vertD.y = patchHeight;                      // outer bottom
+        Vector2 vertA = { 0 };
+        Vector2 vertB = { 0 };
+        Vector2 vertC = { 0 };
+        Vector2 vertD = { 0 };
+        vertA.x = 0.0f;                             // Outer left
+        vertA.y = 0.0f;                             // Outer top
+        vertB.x = leftBorder;                       // Inner left
+        vertB.y = topBorder;                        // Inner top
+        vertC.x = patchWidth  - rightBorder;        // Inner right
+        vertC.y = patchHeight - bottomBorder;       // Inner bottom
+        vertD.x = patchWidth;                       // Outer right
+        vertD.y = patchHeight;                      // Outer bottom
 
-        Vector2 coordA, coordB, coordC, coordD;
+        Vector2 coordA = { 0 };
+        Vector2 coordB = { 0 };
+        Vector2 coordC = { 0 };
+        Vector2 coordD = { 0 };
         coordA.x = nPatchInfo.source.x/width;
         coordA.y = nPatchInfo.source.y/height;
         coordB.x = (nPatchInfo.source.x + leftBorder)/width;
@@ -4907,7 +4921,9 @@ Vector3 ColorToHSV(Color color)
 {
     Vector3 hsv = { 0 };
     Vector3 rgb = { (float)color.r/255.0f, (float)color.g/255.0f, (float)color.b/255.0f };
-    float min, max, delta;
+    float min = 0.0f;
+    float max = 0.0f;
+    float delta = 0.0f;
 
     min = rgb.x < rgb.y? rgb.x : rgb.y;
     min = min  < rgb.z? min  : rgb.z;