Detect depth texture support using INTZ and NULL textures

src/libEGL/Display.cpp

@@ -992,6 +992,22 @@ bool Display::getDXT5TextureSupport()
     return SUCCEEDED(mD3d9->CheckDeviceFormat(mAdapter, mDeviceType, currentDisplayMode.Format, 0, D3DRTYPE_TEXTURE, D3DFMT_DXT5));
 }
 
+// we use INTZ for depth textures in Direct3D9
+// we also want NULL texture support to ensure the we can make depth-only FBOs
+// see http://aras-p.info/texts/D3D9GPUHacks.html
+bool Display::getDepthTextureSupport() const
+{
+    D3DDISPLAYMODE currentDisplayMode;
+    mD3d9->GetAdapterDisplayMode(mAdapter, &currentDisplayMode);
+
+    bool intz = SUCCEEDED(mD3d9->CheckDeviceFormat(mAdapter, mDeviceType, currentDisplayMode.Format,
+                                                   D3DUSAGE_DEPTHSTENCIL, D3DRTYPE_TEXTURE, D3DFMT_INTZ));
+    bool null = SUCCEEDED(mD3d9->CheckDeviceFormat(mAdapter, mDeviceType, currentDisplayMode.Format,
+                                                   D3DUSAGE_RENDERTARGET, D3DRTYPE_SURFACE, D3DFMT_NULL));
+
+    return intz && null;
+}
+
 bool Display::getFloat32TextureSupport(bool *filtering, bool *renderable)
 {
     D3DDISPLAYMODE currentDisplayMode;

src/libEGL/Display.h

@@ -78,6 +78,7 @@ class Display
     virtual bool getLuminanceAlphaTextureSupport();
     virtual bool getVertexTextureSupport() const;
     virtual bool getNonPower2TextureSupport() const;
+    virtual bool getDepthTextureSupport() const;
     virtual bool getOcclusionQuerySupport() const;
     virtual bool getInstancingSupport() const;
     virtual D3DPOOL getBufferPool(DWORD usage) const;

src/libGLESv2/Context.cpp

@@ -310,6 +310,7 @@ void Context::makeCurrent(egl::Display *display, egl::Surface *surface)
         mSupportsFloat16Textures = mDisplay->getFloat16TextureSupport(&mSupportsFloat16LinearFilter, &mSupportsFloat16RenderableTextures);
         mSupportsLuminanceTextures = mDisplay->getLuminanceTextureSupport();
         mSupportsLuminanceAlphaTextures = mDisplay->getLuminanceAlphaTextureSupport();
+        mSupportsDepthTextures = mDisplay->getDepthTextureSupport();
 
         mSupports32bitIndices = mDeviceCaps.MaxVertexIndex >= (1 << 16);
 
@@ -3458,6 +3459,11 @@ bool Context::supportsLuminanceAlphaTextures() const
     return mSupportsLuminanceAlphaTextures;
 }
 
+bool Context::supportsDepthTextures() const
+{
+    return mSupportsDepthTextures;
+}
+
 bool Context::supports32bitIndices() const
 {
     return mSupports32bitIndices;

src/libGLESv2/Context.h

@@ -496,6 +496,7 @@ class Context
     bool supportsFloat16RenderableTextures() const;
     bool supportsLuminanceTextures() const;
     bool supportsLuminanceAlphaTextures() const;
+    bool supportsDepthTextures() const;
     bool supports32bitIndices() const;
     bool supportsNonPower2Texture() const;
     bool supportsInstancing() const;
@@ -618,6 +619,7 @@ class Context
     bool mSupportsFloat16RenderableTextures;
     bool mSupportsLuminanceTextures;
     bool mSupportsLuminanceAlphaTextures;
+    bool mSupportsDepthTextures;
     bool mSupports32bitIndices;
     int mNumCompressedTextureFormats;
 

src/libGLESv2/utilities.h

@@ -16,6 +16,9 @@
 
 #include <string>
 
+const D3DFORMAT D3DFMT_INTZ = ((D3DFORMAT)(MAKEFOURCC('I','N','T','Z')));
+const D3DFORMAT D3DFMT_NULL = ((D3DFORMAT)(MAKEFOURCC('N','U','L','L')));
+
 namespace gl
 {