Merge pull request #6141 from JonnyH/WIP/shader-framebuffer-fetch2

Implement dual-source blending in shader

1 files changed, 70 insertions, 45 deletions

diff --git a/Source/Core/VideoBackends/OGL/Render.cpp b/Source/Core/VideoBackends/OGL/Render.cpp
index 428492c72a..9ee96bb724 100644
--- a/Source/Core/VideoBackends/OGL/Render.cpp
+++ b/Source/Core/VideoBackends/OGL/Render.cpp
@@ -508,12 +508,12 @@ Renderer::Renderer()
             1 :
             GLExtensions::Supports("GL_EXT_geometry_point_size") ? 2 : 0;
     g_ogl_config.SupportedESTextureBuffer = GLExtensions::Supports("VERSION_GLES_3_2") ?
-                                                ES_TEXBUF_TYPE::TEXBUF_CORE :
+                                                EsTexbufType::TexbufCore :
                                                 GLExtensions::Supports("GL_OES_texture_buffer") ?
-                                                ES_TEXBUF_TYPE::TEXBUF_OES :
+                                                EsTexbufType::TexbufOes :
                                                 GLExtensions::Supports("GL_EXT_texture_buffer") ?
-                                                ES_TEXBUF_TYPE::TEXBUF_EXT :
-                                                ES_TEXBUF_TYPE::TEXBUF_NONE;
+                                                EsTexbufType::TexbufExt :
+                                                EsTexbufType::TexbufNone;
 
     g_ogl_config.bSupportsGLSLCache = true;
     g_ogl_config.bSupportsGLSync = true;
@@ -522,16 +522,31 @@ Renderer::Renderer()
     // depth clamping.
     g_Config.backend_info.bSupportsDepthClamp = false;
 
+    if (GLExtensions::Supports("GL_EXT_shader_framebuffer_fetch"))
+    {
+      g_ogl_config.SupportedFramebufferFetch = EsFbFetchType::FbFetchExt;
+    }
+    else if (GLExtensions::Supports("GL_ARM_shader_framebuffer_fetch"))
+    {
+      g_ogl_config.SupportedFramebufferFetch = EsFbFetchType::FbFetchArm;
+    }
+    else
+    {
+      g_ogl_config.SupportedFramebufferFetch = EsFbFetchType::FbFetchNone;
+    }
+    g_Config.backend_info.bSupportsFramebufferFetch =
+        g_ogl_config.SupportedFramebufferFetch != EsFbFetchType::FbFetchNone;
+
     if (GLExtensions::Version() == 300)
     {
-      g_ogl_config.eSupportedGLSLVersion = GLSLES_300;
+      g_ogl_config.eSupportedGLSLVersion = GlslEs300;
       g_ogl_config.bSupportsAEP = false;
       g_ogl_config.bSupportsTextureStorage = true;
       g_Config.backend_info.bSupportsGeometryShaders = false;
     }
     else if (GLExtensions::Version() == 310)
     {
-      g_ogl_config.eSupportedGLSLVersion = GLSLES_310;
+      g_ogl_config.eSupportedGLSLVersion = GlslEs310;
       g_ogl_config.bSupportsAEP = GLExtensions::Supports("GL_ANDROID_extension_pack_es31a");
       g_Config.backend_info.bSupportsBindingLayout = true;
       g_ogl_config.bSupportsImageLoadStore = true;
@@ -556,7 +571,7 @@ Renderer::Renderer()
     }
     else
     {
-      g_ogl_config.eSupportedGLSLVersion = GLSLES_320;
+      g_ogl_config.eSupportedGLSLVersion = GlslEs320;
       g_ogl_config.bSupportsAEP = GLExtensions::Supports("GL_ANDROID_extension_pack_es31a");
       g_Config.backend_info.bSupportsBindingLayout = true;
       g_ogl_config.bSupportsImageLoadStore = true;
@@ -589,7 +604,7 @@ Renderer::Renderer()
     }
     else if (GLExtensions::Version() == 300)
     {
-      g_ogl_config.eSupportedGLSLVersion = GLSL_130;
+      g_ogl_config.eSupportedGLSLVersion = Glsl130;
       g_ogl_config.bSupportsImageLoadStore = false;  // layout keyword is only supported on glsl150+
       g_ogl_config.bSupportsConservativeDepth =
           false;  // layout keyword is only supported on glsl150+
@@ -598,7 +613,7 @@ Renderer::Renderer()
     }
     else if (GLExtensions::Version() == 310)
     {
-      g_ogl_config.eSupportedGLSLVersion = GLSL_140;
+      g_ogl_config.eSupportedGLSLVersion = Glsl140;
       g_ogl_config.bSupportsImageLoadStore = false;  // layout keyword is only supported on glsl150+
       g_ogl_config.bSupportsConservativeDepth =
           false;  // layout keyword is only supported on glsl150+
@@ -607,16 +622,16 @@ Renderer::Renderer()
     }
     else if (GLExtensions::Version() == 320)
     {
-      g_ogl_config.eSupportedGLSLVersion = GLSL_150;
+      g_ogl_config.eSupportedGLSLVersion = Glsl150;
     }
     else if (GLExtensions::Version() == 330)
     {
-      g_ogl_config.eSupportedGLSLVersion = GLSL_330;
+      g_ogl_config.eSupportedGLSLVersion = Glsl330;
     }
     else if (GLExtensions::Version() >= 430)
     {
       // TODO: We should really parse the GL_SHADING_LANGUAGE_VERSION token.
-      g_ogl_config.eSupportedGLSLVersion = GLSL_430;
+      g_ogl_config.eSupportedGLSLVersion = Glsl430;
       g_ogl_config.bSupportsTextureStorage = true;
       g_ogl_config.bSupportsImageLoadStore = true;
       g_Config.backend_info.bSupportsSSAA = true;
@@ -628,7 +643,7 @@ Renderer::Renderer()
     }
     else
     {
-      g_ogl_config.eSupportedGLSLVersion = GLSL_400;
+      g_ogl_config.eSupportedGLSLVersion = Glsl400;
       g_Config.backend_info.bSupportsSSAA = true;
 
       if (GLExtensions::Version() == 420)
@@ -1275,44 +1290,54 @@ void Renderer::SetBlendingState(const BlendingState& state)
   bool useDualSource =
       state.usedualsrc && g_ActiveConfig.backend_info.bSupportsDualSourceBlend &&
       (!DriverDetails::HasBug(DriverDetails::BUG_BROKEN_DUAL_SOURCE_BLENDING) || state.dstalpha);
+  // Only use shader blend if we need to and we don't support dual-source blending directly
+  bool useShaderBlend = !useDualSource && state.usedualsrc && state.dstalpha &&
+                        g_ActiveConfig.backend_info.bSupportsFramebufferFetch;
 
-  const GLenum src_factors[8] = {
-      GL_ZERO,
-      GL_ONE,
-      GL_DST_COLOR,
-      GL_ONE_MINUS_DST_COLOR,
-      useDualSource ? GL_SRC1_ALPHA : (GLenum)GL_SRC_ALPHA,
-      useDualSource ? GL_ONE_MINUS_SRC1_ALPHA : (GLenum)GL_ONE_MINUS_SRC_ALPHA,
-      GL_DST_ALPHA,
-      GL_ONE_MINUS_DST_ALPHA};
-  const GLenum dst_factors[8] = {
-      GL_ZERO,
-      GL_ONE,
-      GL_SRC_COLOR,
-      GL_ONE_MINUS_SRC_COLOR,
-      useDualSource ? GL_SRC1_ALPHA : (GLenum)GL_SRC_ALPHA,
-      useDualSource ? GL_ONE_MINUS_SRC1_ALPHA : (GLenum)GL_ONE_MINUS_SRC_ALPHA,
-      GL_DST_ALPHA,
-      GL_ONE_MINUS_DST_ALPHA};
-
-  if (state.blendenable)
+  if (useShaderBlend)
   {
-    glEnable(GL_BLEND);
+    glDisable(GL_BLEND);
   }
   else
   {
-    glDisable(GL_BLEND);
-  }
+    const GLenum src_factors[8] = {
+        GL_ZERO,
+        GL_ONE,
+        GL_DST_COLOR,
+        GL_ONE_MINUS_DST_COLOR,
+        useDualSource ? GL_SRC1_ALPHA : (GLenum)GL_SRC_ALPHA,
+        useDualSource ? GL_ONE_MINUS_SRC1_ALPHA : (GLenum)GL_ONE_MINUS_SRC_ALPHA,
+        GL_DST_ALPHA,
+        GL_ONE_MINUS_DST_ALPHA};
+    const GLenum dst_factors[8] = {
+        GL_ZERO,
+        GL_ONE,
+        GL_SRC_COLOR,
+        GL_ONE_MINUS_SRC_COLOR,
+        useDualSource ? GL_SRC1_ALPHA : (GLenum)GL_SRC_ALPHA,
+        useDualSource ? GL_ONE_MINUS_SRC1_ALPHA : (GLenum)GL_ONE_MINUS_SRC_ALPHA,
+        GL_DST_ALPHA,
+        GL_ONE_MINUS_DST_ALPHA};
+
+    if (state.blendenable)
+    {
+      glEnable(GL_BLEND);
+    }
+    else
+    {
+      glDisable(GL_BLEND);
+    }
 
-  // Always call glBlendEquationSeparate and glBlendFuncSeparate, even when
-  // GL_BLEND is disabled, as a workaround for some bugs (possibly graphics
-  // driver issues?). See https://bugs.dolphin-emu.org/issues/10120 : "Sonic
-  // Adventure 2 Battle: graphics crash when loading first Dark level"
-  GLenum equation = state.subtract ? GL_FUNC_REVERSE_SUBTRACT : GL_FUNC_ADD;
-  GLenum equationAlpha = state.subtractAlpha ? GL_FUNC_REVERSE_SUBTRACT : GL_FUNC_ADD;
-  glBlendEquationSeparate(equation, equationAlpha);
-  glBlendFuncSeparate(src_factors[state.srcfactor], dst_factors[state.dstfactor],
-                      src_factors[state.srcfactoralpha], dst_factors[state.dstfactoralpha]);
+    // Always call glBlendEquationSeparate and glBlendFuncSeparate, even when
+    // GL_BLEND is disabled, as a workaround for some bugs (possibly graphics
+    // driver issues?). See https://bugs.dolphin-emu.org/issues/10120 : "Sonic
+    // Adventure 2 Battle: graphics crash when loading first Dark level"
+    GLenum equation = state.subtract ? GL_FUNC_REVERSE_SUBTRACT : GL_FUNC_ADD;
+    GLenum equationAlpha = state.subtractAlpha ? GL_FUNC_REVERSE_SUBTRACT : GL_FUNC_ADD;
+    glBlendEquationSeparate(equation, equationAlpha);
+    glBlendFuncSeparate(src_factors[state.srcfactor], dst_factors[state.dstfactor],
+                        src_factors[state.srcfactoralpha], dst_factors[state.dstfactoralpha]);
+  }
 
   const GLenum logic_op_codes[16] = {
       GL_CLEAR,         GL_AND,         GL_AND_REVERSE, GL_COPY,  GL_AND_INVERTED, GL_NOOP,