texRECTproj
Keywords: texRECTproj, NVIDIA, NVIDIA Cg Toolkit, Cg Toolkit, Shader, Shader Programming, GPU Shader Programming, GPU Program

> ## Name

> texRECTproj - performs a texture lookup with projection in a given sampler. May perform a shadow comparison if argument for shadow comparison is provided.

> ## Synopsis

>     float4 texRECTproj(samplerRECT samp, float3 s)
>     float4 texRECTproj(samplerRECT samp, float3 s, int texelOff)
>     float4 texRECTproj(samplerRECT samp, float4 s)
>     float4 texRECTproj(samplerRECT samp, float4 s, int texelOff)

>     int4 texRECTproj(isamplerRECT samp, float3 s)
>     int4 texRECTproj(isamplerRECT samp, float3 s, int texelOff)

>     unsigned int4 texRECTproj(usamplerRECT samp, float3 s)
>     unsigned int4 texRECTproj(usamplerRECT samp, float3 s, int texelOff)

> ## Parameters

> samp
>   Sampler to lookup.
> s
>   Coordinates to perform the lookup. The value used in the projection should be passed as the last component of the coordinate vector. The value used in the shadow comparison, if present, should be passed as the next-to-last component of the coordinate vector.
> texelOff
>   Offset to be added to obtain the final texel.

> ## Description

> Performs a texture lookup in sampler samp using coordinates s, the coordinates used in the lookup are first projected, that is, divided by the last component of the coordinate vector and then used in the lookup. If an extra coordinate is present it is used to perform a shadow comparison, the value used in the shadow comparison is always the next-to-last component in the coordinate vector.

> ## Profile Support

> texRECTproj is supported in all fragment profiles and all vertex profiles starting with vp40, variants with shadow comparison are only supported in fp40 and newer profiles, variants with texel offsets are only supported in gp4 and newer profiles.

> ## See Also

> texRECT