Fixes GL internal format of textures in compute

In compute shaders load/store operations requires sized formats.

source/renderer/PostprocManager.cpp

@@ -215,7 +215,7 @@ void CPostprocManager::InitializePBR()
 			LOGWARNING("%s is unsupported", framebufferFormatName);
 	}
 
-	if (m_Device->GetCapabilities().computeShaders && m_Device->GetCapabilities().storage)
+	if (m_Device->GetCapabilities().computeShaders)
 	{
 		m_ResolvePBRComputeTech = g_Renderer.GetShaderManager().LoadEffect(str_compute_resolve_pbr);
 		if (m_ResolvePBRComputeTech)

source/renderer/backend/gl/Texture.cpp

@@ -174,6 +174,12 @@ std::unique_ptr<CTexture> CTexture::Create(
 		// pixel format.
 		GLenum pixelFormat = GL_RGBA;
 		GLenum pixelType = GL_UNSIGNED_BYTE;
+#if !CONFIG2_GLES
+		// load/store operation requires sized formats. See Table 8.25:
+		//   https://registry.khronos.org/OpenGL/specs/gl/glspec43.core.pdf
+		if (usage & ITexture::Usage::STORAGE)
+			internalFormat = GL_RGBA8;
+#endif
 		switch (format)
 		{
 		case Format::UNDEFINED: