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The following features were changed in Microsoft Direct3D 9. If you are using these features, see the changes listed below to help you port your application to Direct3D 9.
In DirectX 8.x, IDirect3DDevice8::SetIndices required a pointer to the index buffer and a BaseVertexIndex for the starting position in the vertex buffer. An application batching different objects into the vertex buffer had to switch the index buffer (or make a call to IDirect3DDevice8::SetIndices) before calling IDirect3DDevice8::DrawIndexedPrimitive.
In Direct3D 9, the starting position in the vertex buffer, BaseVertexIndex, has been moved to IDirect3DDevice9::DrawIndexedPrimitive, and its data type changed from a DWORD to an INT.
HRESULT IDirect3DDevice9::DrawIndexedPrimitive(
D3DPRIMITIVETYPE PrimType,
INT BaseVertexIndex,
UINT minIndex,
UINT NumVertices,
UINT startIndex,
UINT primCount);
HRESULT SetIndices(IDirect3DIndexBuffer9* pIndexData);
IDirect3DDevice8::CreateImageSurface was renamed IDirect3DDevice9::CreateOffscreenPlainSurface. An additional parameter that takes a D3DPOOL type was added. D3DPOOL_SCRATCH will return a surface that has identical characteristics to a surface created by IDirect3DDevice8::CreateImageSurface. D3DPOOL_DEFAULT is the appropriate pool for use with IDirect3DDevice9::StretchRect and IDirect3DDevice9::ColorFill.
Applications now have to explicitly ask for the Microsoft Windows Hardware Quality Labs (WHQL) because the response takes relatively long (a few seconds). D3DENUM_NO_WHQL_LEVEL has been removed and D3DENUM_WHQL_LEVEL has been added.
A handle has been added to several methods and should be set to NULL. The methods affected include:
The IDirect3D9::EnumAdapterModes now takes a D3DFORMAT.
HRESULT IDirect3D9::EnumAdapterModes(
UINT Adapter,
D3DFORMAT Format,
UINT Mode,
D3DDISPLAYMODE *pMode);
The format supports an expanding set of display modes. To protect applications from enumerating formats that were not invented when the application shipped, the application must tell Direct3D the format for the display modes that should be enumerated. The resulting array of display modes will differ only by width, height, and refresh rate.
The application specifies a pixel format and the enumeration is restricted to those display modes that exactly match the format. The following is a list of the allowed formats:
Enumeration is equivalent for alpha and nonalpha versions of the same format. The returned Format will always be filled with the same format supplied by the application.
This method treats 565 and 555 as equivalent, and returns the correct version in the Format. The difference comes into play only when the application locks the back buffer, and there is an explicit flag that the application must set in order to accomplish this.
One parameter has been added to the IDirect3DDevice9::GetStreamSource and IDirect3DDevice9::SetStreamSource methods. The offset is the number of bytes between the beginning of the stream and the beginning of the vertex data. It is measured in bytes. This enables the pipeline to support stream offsets. To find out if the device supports stream offsets, see D3DDEVCAPS2_STREAMOFFSET.
HRESULT GetStreamSource(
UINT StreamNumber,
IDirect3DVertexBuffer9 **ppStreamData,
UINT *pOffsetInBytes,
UINT *pStride);
Previously, there was only the D3DMULTISAMPLE_TYPE enumeration. Direct3D 9 retains this enumeration and adds the idea of a quality level for each element of the enumeration. The quality level indicates a trade-off between visual quality and performance by indicating the number of maskable samples (in the sense of D3DRS_MULTISAMPLEMASK).
An application should choose how many maskable samples it requires, and then consult pQualityLevels. If nonzero, this value indicates the number of quality levels the application can pass to the various creation functions through MultiSampleQuality. Because drivers expose all their multisample schemes as quality levels at D3DMULTISAMPLE_NONMASKABLE, you can enumerate all available multisampling schemes through this one type if your application does not need to mask samples.
The D3DPRASTERCAPS_STRETCHBLTMULTISAMPLE caps bit has been retired. This bit used to mean that the multisampling method did not support write masks, and could not be toggled on and off between IDirect3DDevice9::BeginScene and IDirect3DDevice9::EndScene. Such nonmaskable methods are now exposed through D3DMULTISAMPLE_NONMASKABLE.
HRESULT CheckDeviceMultiSampleType(
UINT Adapter,
D3DDEVTYPE DeviceType,
D3DFORMAT SurfaceFormat,
BOOL Windowed,
D3DMULTISAMPLE_TYPE MultiSampleType,
DWORD * pQualityLevels);
There is a different maximum for each number of maskable samples. For example, D3DMULTISAMPLE_4_SAMPLES might have three levels of quality, while D3DMULTISAMPLE_2_SAMPLES might have only one. There are at most eight levels of quality for each number of maskable samples (the driver is not allowed to express more). The quality ranges from zero to (*pQualityLevels - 1).
ResourceManagerDiscardBytes has been replaced by IDirect3DDevice9::EvictManagedResources. It can evict all resources, both Direct3D and driver resources.
The resource manager is now consulted when a resource (whether managed or nonmanaged) fails creation because there is insufficient video memory. The manager will automatically be asked to free enough resources for the creation to succeed. In DirectX 8.0, this was not an automated process.
An application can create a mixed-mode device to use software and hardware vertex processing.
To switch between the two vertex processing modes in DirectX 8.x, call IDirect3DDevice8::SetRenderState. This has been replaced with IDirect3DDevice9::SetSoftwareVertexProcessing to ease problems caused by state blocks. This new method is not recorded by state blocks.
Direct3D 9 supports up to sixteen texture surfaces in one pass using the pixel shader 2_0 model; however, the number of texture coordinates remains limited to eight. Texture stage state is associated with surfaces, coordinate sets, vertex processing, and pixel processing. To manage these differences at compile time, IDirect3DDevice9::SetTextureStageState has been broken into two methods:
IDirect3DDevice9::SetTextureStageState now sets the following states:
The number of fixed function pixel shader states that can be set is less than or equal to the number represented by MaxTextureBlendStages.
The number of texture samplers available to the application is determined by the pixel shader version, as indicated in the following table.
| Name | Number |
|---|---|
| ps_1_1 to ps_1_3 | 4 texture samplers |
| ps_1_4 | 6 texture samplers |
| ps_2_0 | 16 texture samplers |
| fixed function pipeline | MaxTextureBlendStages/MaxSimultaneousTextures texture samplers |
Devices that support displacement mapping in Direct3D 9 will support an additional sampler (D3DDMAPSAMPLER), which samples the displacement maps in the tessellator unit.
IDirect3DDevice9::SetSamplerState sets the sampler state (including the one used in the tessellator unit to sample displacement maps). These have been renamed with a D3DSAMP_ prefix to enable compile-time error detection when porting from DirectX 8.x. The states include:
Vertex declarations are now decoupled from vertex shader creation. Vertex declarations now use a Component Object Model (COM) interface.
For DirectX 8.x, vertex declarations are tied to vertex shaders.
For Direct3D 9, vertex declarations are decoupled from vertex shaders and they can be used with either the fixed function pipeline or with shaders.
Several changes were made to give the user more control over monitor refresh rate, presentation rate, and front-buffer versus back-buffer drawing. They are as follows:
For a detailed explanation of the modes and the intervals that are supported, see D3DPRESENT.