Use floating point z-buffer in D3D9 driver if possible.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@2283 dfc29bdd-3216-0410-991c-e03cc46cb475

source/Irrlicht/CD3D9Driver.cpp

@@ -303,6 +303,11 @@ bool CD3D9Driver::initDriver(const core::dimension2d<u32>& screenSize,
 
 	// check stencil buffer compatibility
 	if (StencilBuffer)
+	{
+		present.AutoDepthStencilFormat = D3DFMT_D24FS8;
+		if(FAILED(pID3D->CheckDeviceFormat(adapter, devtype,
+			present.BackBufferFormat, D3DUSAGE_DEPTHSTENCIL,
+			D3DRTYPE_SURFACE, present.AutoDepthStencilFormat)))
 		{
 			present.AutoDepthStencilFormat = D3DFMT_D24S8;
 			if(FAILED(pID3D->CheckDeviceFormat(adapter, devtype,
@@ -324,6 +329,7 @@ bool CD3D9Driver::initDriver(const core::dimension2d<u32>& screenSize,
 					}
 				}
 			}
+		}
 		else
 		if(FAILED(pID3D->CheckDepthStencilMatch(adapter, devtype,
 			present.BackBufferFormat, present.BackBufferFormat, present.AutoDepthStencilFormat)))
@@ -334,6 +340,11 @@ bool CD3D9Driver::initDriver(const core::dimension2d<u32>& screenSize,
 	}
 	// do not use else here to cope with flag change in previous block
 	if (!StencilBuffer)
+	{
+		present.AutoDepthStencilFormat = D3DFMT_D32F_LOCKABLE;
+		if(FAILED(pID3D->CheckDeviceFormat(adapter, devtype,
+			present.BackBufferFormat, D3DUSAGE_DEPTHSTENCIL,
+			D3DRTYPE_SURFACE, present.AutoDepthStencilFormat)))
 		{
 			present.AutoDepthStencilFormat = D3DFMT_D32;
 			if(FAILED(pID3D->CheckDeviceFormat(adapter, devtype,
@@ -356,6 +367,7 @@ bool CD3D9Driver::initDriver(const core::dimension2d<u32>& screenSize,
 				}
 			}
 		}
+	}
 
 	// create device