Continuation of support for ES3/WebGL2 (#3107)

* Continuation of support for ES3/WebGL2

* GetTouchPointState()

* Amends to the WebGL2 PR

---------

Co-authored-by: root <root@DESKTOP-GLOV9QV>
Co-authored-by: chemguerra <online@chemaguerra.com>

src/Makefile

@@ -246,6 +246,7 @@ endif
 ifeq ($(PLATFORM),PLATFORM_WEB)
     # On HTML5 OpenGL ES 2.0 is used, emscripten translates it to WebGL 1.0
     GRAPHICS = GRAPHICS_API_OPENGL_ES2
+    #GRAPHICS = GRAPHICS_API_OPENGL_ES3      # Uncomment to use ES3/WebGL2 (preliminary support).
 endif
 ifeq ($(PLATFORM),PLATFORM_ANDROID)
     # By default use OpenGL ES 2.0 on Android

src/rlgl.h

@@ -148,7 +148,8 @@
     !defined(GRAPHICS_API_OPENGL_21) && \
     !defined(GRAPHICS_API_OPENGL_33) && \
     !defined(GRAPHICS_API_OPENGL_43) && \
-    !defined(GRAPHICS_API_OPENGL_ES2)
+    !defined(GRAPHICS_API_OPENGL_ES2) && \
+    !defined(GRAPHICS_API_OPENGL_ES3)
         #define GRAPHICS_API_OPENGL_33
 #endif
 
@@ -1711,7 +1712,7 @@ void rlDisableFramebuffer(void)
 // NOTE: One color buffer is always active by default
 void rlActiveDrawBuffers(int count)
 {
-#if (defined(GRAPHICS_API_OPENGL_33) && defined(RLGL_RENDER_TEXTURES_HINT))
+#if ((defined(GRAPHICS_API_OPENGL_33) || defined(GRAPHICS_API_OPENGL_ES3)) && defined(RLGL_RENDER_TEXTURES_HINT))
     // NOTE: Maximum number of draw buffers supported is implementation dependant,
     // it can be queried with glGet*() but it must be at least 8
     //GLint maxDrawBuffers = 0;
@@ -1723,6 +1724,16 @@ void rlActiveDrawBuffers(int count)
         else
         {
             unsigned int buffers[8] = {
+#if defined(GRAPHICS_API_OPENGL_ES3)
+                GL_COLOR_ATTACHMENT0_EXT,
+                GL_COLOR_ATTACHMENT1_EXT,
+                GL_COLOR_ATTACHMENT2_EXT,
+                GL_COLOR_ATTACHMENT3_EXT,
+                GL_COLOR_ATTACHMENT4_EXT,
+                GL_COLOR_ATTACHMENT5_EXT,
+                GL_COLOR_ATTACHMENT6_EXT,
+                GL_COLOR_ATTACHMENT7_EXT,
+#else
                 GL_COLOR_ATTACHMENT0,
                 GL_COLOR_ATTACHMENT1,
                 GL_COLOR_ATTACHMENT2,
@@ -1731,9 +1742,14 @@ void rlActiveDrawBuffers(int count)
                 GL_COLOR_ATTACHMENT5,
                 GL_COLOR_ATTACHMENT6,
                 GL_COLOR_ATTACHMENT7,
+#endif
             };
 
+#if defined(GRAPHICS_API_OPENGL_ES3)
+            glDrawBuffersEXT(count, buffers);
+#else
             glDrawBuffers(count, buffers);
+#endif
         }
     }
     else TRACELOG(LOG_WARNING, "GL: One color buffer active by default");
@@ -2201,7 +2217,29 @@ void rlLoadExtensions(void *loader)
 
 #endif  // GRAPHICS_API_OPENGL_33
 
-#if defined(GRAPHICS_API_OPENGL_ES2)
+#if defined(GRAPHICS_API_OPENGL_ES3)
+    // Register supported extensions flags
+    // OpenGL ES 3.0 extensions supported by default
+    RLGL.ExtSupported.vao = true;
+    RLGL.ExtSupported.instancing = true;
+    RLGL.ExtSupported.texNPOT = true;
+    RLGL.ExtSupported.texFloat32 = true;
+    RLGL.ExtSupported.texDepth = true;
+    RLGL.ExtSupported.texDepthWebGL = true;
+    RLGL.ExtSupported.maxDepthBits = 24;
+    RLGL.ExtSupported.texAnisoFilter = true;
+    RLGL.ExtSupported.texMirrorClamp = true;
+    // TODO: Make sure that the ones above are actually present by default
+    // TODO: Check for these...
+    //       RLGL.ExtSupported.texCompDXT
+    //       RLGL.ExtSupported.texCompETC1
+    //       RLGL.ExtSupported.texCompETC2
+    //       RLGL.ExtSupported.texCompPVRT
+    //       RLGL.ExtSupported.texCompASTC
+    //       RLGL.ExtSupported.computeShader
+    //       RLGL.ExtSupported.ssbo
+    //       RLGL.ExtSupported.maxAnisotropyLevel
+#elif defined(GRAPHICS_API_OPENGL_ES2)
 
     #if defined(PLATFORM_DESKTOP)
     // TODO: Support OpenGL ES 3.0
@@ -3057,7 +3095,7 @@ unsigned int rlLoadTextureDepth(int width, int height, bool useRenderBuffer)
     // Possible formats: GL_DEPTH_COMPONENT16, GL_DEPTH_COMPONENT24, GL_DEPTH_COMPONENT32 and GL_DEPTH_COMPONENT32F
     unsigned int glInternalFormat = GL_DEPTH_COMPONENT;
 
-#if defined(GRAPHICS_API_OPENGL_ES2)
+#if (defined(GRAPHICS_API_OPENGL_ES2) || defined(GRAPHICS_API_OPENGL_ES3))
     // WARNING: WebGL platform requires unsized internal format definition (GL_DEPTH_COMPONENT)
     // while other platforms using OpenGL ES 2.0 require/support sized internal formats depending on the GPU capabilities
     if (!RLGL.ExtSupported.texDepthWebGL || useRenderBuffer)
@@ -3214,10 +3252,16 @@ void rlGetGlTextureFormats(int format, unsigned int *glInternalFormat, unsigned
         case RL_PIXELFORMAT_UNCOMPRESSED_R4G4B4A4: *glInternalFormat = GL_RGBA; *glFormat = GL_RGBA; *glType = GL_UNSIGNED_SHORT_4_4_4_4; break;
         case RL_PIXELFORMAT_UNCOMPRESSED_R8G8B8A8: *glInternalFormat = GL_RGBA; *glFormat = GL_RGBA; *glType = GL_UNSIGNED_BYTE; break;
         #if !defined(GRAPHICS_API_OPENGL_11)
+        #if defined(GRAPHICS_API_OPENGL_ES3)
+        case RL_PIXELFORMAT_UNCOMPRESSED_R32: if (RLGL.ExtSupported.texFloat32) *glInternalFormat = GL_R32F_EXT; *glFormat = GL_RED_EXT; *glType = GL_FLOAT; break;
+        case RL_PIXELFORMAT_UNCOMPRESSED_R32G32B32: if (RLGL.ExtSupported.texFloat32) *glInternalFormat = GL_RGB32F_EXT; *glFormat = GL_RGB; *glType = GL_FLOAT; break;
+        case RL_PIXELFORMAT_UNCOMPRESSED_R32G32B32A32: if (RLGL.ExtSupported.texFloat32) *glInternalFormat = GL_RGBA32F_EXT; *glFormat = GL_RGBA; *glType = GL_FLOAT; break;
+        #else
         case RL_PIXELFORMAT_UNCOMPRESSED_R32: if (RLGL.ExtSupported.texFloat32) *glInternalFormat = GL_LUMINANCE; *glFormat = GL_LUMINANCE; *glType = GL_FLOAT; break;   // NOTE: Requires extension OES_texture_float
         case RL_PIXELFORMAT_UNCOMPRESSED_R32G32B32: if (RLGL.ExtSupported.texFloat32) *glInternalFormat = GL_RGB; *glFormat = GL_RGB; *glType = GL_FLOAT; break;         // NOTE: Requires extension OES_texture_float
         case RL_PIXELFORMAT_UNCOMPRESSED_R32G32B32A32: if (RLGL.ExtSupported.texFloat32) *glInternalFormat = GL_RGBA; *glFormat = GL_RGBA; *glType = GL_FLOAT; break;    // NOTE: Requires extension OES_texture_float
         #endif
+        #endif
     #elif defined(GRAPHICS_API_OPENGL_33)
         case RL_PIXELFORMAT_UNCOMPRESSED_GRAYSCALE: *glInternalFormat = GL_R8; *glFormat = GL_RED; *glType = GL_UNSIGNED_BYTE; break;
         case RL_PIXELFORMAT_UNCOMPRESSED_GRAY_ALPHA: *glInternalFormat = GL_RG8; *glFormat = GL_RG; *glType = GL_UNSIGNED_BYTE; break;