[d3d8] Use D3DPOOL_SCRATCH in CreateImageSurface

src/d3d8/d3d8_device.cpp

@@ -436,14 +436,15 @@ namespace dxvk {
   }
 
   HRESULT STDMETHODCALLTYPE D3D8Device::CreateImageSurface(UINT Width, UINT Height, D3DFORMAT Format, IDirect3DSurface8** ppSurface) {
+    // TODO: Use D3DPOOL_SCRATCH globally, not only for unsupported surface formats (depends on CopyRects support)
+    d3d9::D3DPOOL pool = isUnsupportedSurfaceFormat(Format) ? d3d9::D3DPOOL_SCRATCH : d3d9::D3DPOOL_SYSTEMMEM;
 
     Com<d3d9::IDirect3DSurface9> pSurf = nullptr;
     HRESULT res = GetD3D9()->CreateOffscreenPlainSurface(
       Width,
       Height,
       d3d9::D3DFORMAT(Format),
-      // FIXME: D3DPOOL_SCRATCH is said to be dx8 compatible, but currently won't work with CopyRects
-      d3d9::D3DPOOL_SYSTEMMEM,
+      pool,
       &pSurf,
       NULL);
 

src/d3d8/d3d8_format.h

@@ -15,6 +15,17 @@ namespace dxvk {
     return isDXT(D3DFORMAT(fmt));
   }
 
+  inline constexpr bool isUnsupportedSurfaceFormat(D3DFORMAT fmt) {
+    // mirror what dxvk doesn't support in terms of d3d9 surface formats
+    return fmt == D3DFMT_R8G8B8
+        || fmt == D3DFMT_R3G3B2
+        || fmt == D3DFMT_A8R3G3B2
+        || fmt == D3DFMT_A8P8
+        || fmt == D3DFMT_P8;
+        // not included in the d3d8 spec
+        //|| fmt == D3DFMT_CXV8U8;
+  }
+
   inline constexpr bool isSupportedDepthStencilFormat(D3DFORMAT fmt) {
     // native d3d8 doesn't support D3DFMT_D32, D3DFMT_D15S1 or D3DFMT_D24X4S4
     return fmt == D3DFMT_D16_LOCKABLE