How to set Alpha value from pixel shader in SlimDX Direct3d9
- by Yashwinder
I am trying to set alpha value of color as color.a = 0.5f in my pixel shader but all the time it is giving an exception. I can set color.r, color.g, color.b but it is not allowing me to set color.a and throwing an exception D3DERR_INVALIDCALL: Invalid call (-2005530516).
I have just created a direct3d9 device and assigned my pixel shader to it.
My pixel shader code is as below
sampler2D ourImage : register(s0);
float4 main(float2 locationInSource : TEXCOORD) : COLOR
{
float4 color = tex2D( ourImage , locationInSource.xy);
color.a = 0.2;
return color;
}
I am creating my pixel shader as
byte[] byteCode = GiveFxFile(transitionEffect.PixelShaderFileName);
var shaderBytecode = ShaderBytecode.Compile(byteCode, "main", "ps_2_0", ShaderFlags.None);
var pixelShader = new PixelShader(device, ShaderBytecode);
_device.PixelShader=pixelShader;
I have initialized my device as
var _presentParams = new PresentParameters
{
Windowed = _isWindowedMode,
BackBufferWidth = (int)SystemParameters.PrimaryScreenWidth,
BackBufferHeight = (int)SystemParameters.PrimaryScreenHeight,
// Enable Z-Buffer
// This is not really needed in this sample but real applications generaly use it
EnableAutoDepthStencil = true,
AutoDepthStencilFormat = Format.D16,
// How to swap backbuffer in front and how many per screen refresh
BackBufferCount = 1,
SwapEffect = SwapEffect.Copy,
BackBufferFormat = _direct3D.Adapters[0].CurrentDisplayMode.Format,
PresentationInterval = PresentInterval.Immediate,
DeviceWindowHandle = _windowHandle
};
_device = new Device(_direct3D, 0, DeviceType.Hardware, _windowHandle, deviceFlags | CreateFlags.Multithreaded, _presentParams);
