Merge pull request #31259 from clayjohn/gles2-depth-allocation

Check for unsigned_short support for gles2 depth buffer allocation

drivers/gles2/rasterizer_storage_gles2.cpp

@@ -5691,21 +5691,49 @@ void RasterizerStorageGLES2::initialize() {
 
 		GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
 
+		glBindFramebuffer(GL_FRAMEBUFFER, system_fbo);
+		glDeleteFramebuffers(1, &fbo);
+		glBindTexture(GL_TEXTURE_2D, 0);
+		glDeleteTextures(1, &depth);
+
 		if (status == GL_FRAMEBUFFER_COMPLETE) {
 			config.depth_internalformat = GL_DEPTH_COMPONENT;
 			config.depth_type = GL_UNSIGNED_INT;
 		} else {
+			// If it fails, test to see if it supports a framebuffer texture using UNSIGNED_SHORT
+			// This is needed because many OSX devices don't support either UNSIGNED_INT or UNSIGNED_SHORT
+
 			config.depth_internalformat = GL_DEPTH_COMPONENT16;
 			config.depth_type = GL_UNSIGNED_SHORT;
-		}
 
-		glBindFramebuffer(GL_FRAMEBUFFER, system_fbo);
-		glDeleteFramebuffers(1, &fbo);
-		glBindTexture(GL_TEXTURE_2D, 0);
-		glDeleteTextures(1, &depth);
+			glGenFramebuffers(1, &fbo);
+			glBindFramebuffer(GL_FRAMEBUFFER, fbo);
 
+			glGenTextures(1, &depth);
+			glBindTexture(GL_TEXTURE_2D, depth);
+			glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT16, 32, 32, 0, GL_DEPTH_COMPONENT16, GL_UNSIGNED_SHORT, NULL);
+
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+
+			glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depth, 0);
+
+			status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
+			if (status != GL_FRAMEBUFFER_COMPLETE) {
+				//if it fails again depth textures aren't supported, use rgba shadows and renderbuffer for depth
+				config.support_depth_texture = false;
+				config.use_rgba_3d_shadows = true;
+			}
+
+			glBindFramebuffer(GL_FRAMEBUFFER, system_fbo);
+			glDeleteFramebuffers(1, &fbo);
+			glBindTexture(GL_TEXTURE_2D, 0);
+			glDeleteTextures(1, &depth);
+		}
 	} else {
-		// Will use renderbuffer for depth
+		// Will use renderbuffer for depth, on mobile check for 24 bit depth support
 		if (config.extensions.has("GL_OES_depth24")) {
 			config.depth_internalformat = _DEPTH_COMPONENT24_OES;
 			config.depth_type = GL_UNSIGNED_INT;