Corrected issue with texture flip X

src/textures.c

@@ -2573,7 +2573,7 @@ void DrawTextureEx(Texture2D texture, Vector2 position, float rotation, float sc
 // Draw a part of a texture (defined by a rectangle)
 void DrawTextureRec(Texture2D texture, Rectangle sourceRec, Vector2 position, Color tint)
 {
-    Rectangle destRec = { position.x, position.y, sourceRec.width, (float)fabs(sourceRec.height) };
+    Rectangle destRec = { position.x, position.y, (float)fabs(sourceRec.width), (float)fabs(sourceRec.height) };
     Vector2 origin = { 0.0f, 0.0f };
 
     DrawTexturePro(texture, sourceRec, destRec, origin, 0.0f, tint);
@@ -2599,8 +2599,10 @@ void DrawTexturePro(Texture2D texture, Rectangle sourceRec, Rectangle destRec, V
     {
         float width = (float)texture.width;
         float height = (float)texture.height;
-
-        if (sourceRec.width < 0) sourceRec.x -= sourceRec.width;
+        
+        bool flipX = false;
+        
+        if (sourceRec.width < 0) { flipX = true; sourceRec.width *= -1; }
         if (sourceRec.height < 0) sourceRec.y -= sourceRec.height;
 
         rlEnableTexture(texture.id);
@@ -2615,19 +2617,23 @@ void DrawTexturePro(Texture2D texture, Rectangle sourceRec, Rectangle destRec, V
                 rlNormal3f(0.0f, 0.0f, 1.0f);                          // Normal vector pointing towards viewer
 
                 // Bottom-left corner for texture and quad
-                rlTexCoord2f(sourceRec.x/width, sourceRec.y/height);
+                if (flipX) rlTexCoord2f((sourceRec.x + sourceRec.width)/width, sourceRec.y/height);
+                else rlTexCoord2f(sourceRec.x/width, sourceRec.y/height);
                 rlVertex2f(0.0f, 0.0f);
 
                 // Bottom-right corner for texture and quad
-                rlTexCoord2f(sourceRec.x/width, (sourceRec.y + sourceRec.height)/height);
+                if (flipX) rlTexCoord2f((sourceRec.x + sourceRec.width)/width, (sourceRec.y + sourceRec.height)/height);
+                else rlTexCoord2f(sourceRec.x/width, (sourceRec.y + sourceRec.height)/height);
                 rlVertex2f(0.0f, destRec.height);
 
                 // Top-right corner for texture and quad
-                rlTexCoord2f((sourceRec.x + sourceRec.width)/width, (sourceRec.y + sourceRec.height)/height);
+                if (flipX) rlTexCoord2f(sourceRec.x/width, (sourceRec.y + sourceRec.height)/height);
+                else rlTexCoord2f((sourceRec.x + sourceRec.width)/width, (sourceRec.y + sourceRec.height)/height);
                 rlVertex2f(destRec.width, destRec.height);
 
                 // Top-left corner for texture and quad
-                rlTexCoord2f((sourceRec.x + sourceRec.width)/width, sourceRec.y/height);
+                if (flipX) rlTexCoord2f(sourceRec.x/width, sourceRec.y/height);
+                else rlTexCoord2f((sourceRec.x + sourceRec.width)/width, sourceRec.y/height);
                 rlVertex2f(destRec.width, 0.0f);
             rlEnd();
         rlPopMatrix();