> ## Name

> texRECT - performs a texture lookup in a given RECT sampler and, in some cases, a shadow comparison. May also use pre computed derivatives if those are provided.

> ## Synopsis

>     float4 texRECT(samplerRECT samp, float2 s)
>     float4 texRECT(samplerRECT samp, float2 s, int texelOff)
>     float4 texRECT(samplerRECT samp, float3 s)
>     float4 texRECT(samplerRECT samp, float3 s, int texelOff)

>     float4 texRECT(samplerRECT samp, float2 s, float2 dx, float2 dy)
>     float4 texRECT(samplerRECT samp, float2 s, float2 dx, float2 dy, int texelOff)
>     float4 texRECT(samplerRECT samp, float3 s, float2 dx, float2 dy)
>     float4 texRECT(samplerRECT samp, float3 s, float2 dx, float2 dy, int texelOff)

>     int4 texRECT(isamplerRECT samp, float2 s)
>     int4 texRECT(isamplerRECT samp, float2 s, int texelOff)

>     int4 texRECT(isamplerRECT samp, float2 s, float2 dx, float2 dy)
>     int4 texRECT(isamplerRECT samp, float2 s, float2 dx, float2 dy, int texelOff)

>     unsigned int4 texRECT(usamplerRECT samp, float2 s)
>     unsigned int4 texRECT(usamplerRECT samp, float2 s, int texelOff)

>     unsigned int4 texRECT(usamplerRECT samp, float2 s, float2 dx, float2 dy)
>     unsigned int4 texRECT(usamplerRECT samp, float2 s, float2 dx, float2 dy,
>                           int texelOff)

> ## Parameters

> samp
>   Sampler to lookup.
> s
>   Coordinates to perform the lookup. If an extra coordinate compared to the texture dimensionality is present it is used to perform a shadow comparison. The value used in the shadow comparison is always the last component of the coordinate vector.
> dx
>   Pre computed derivative along the x axis.
> dy
>   Pre computed derivative along the y axis.
> texelOff
>   Offset to be added to obtain the final texel.

> ## Description

> Performs a texture lookup in sampler samp using coordinates s, may use and derivatives dx and dy, also may perform shadow comparison and use texel offset texelOff to compute final texel.

> ## Profile Support

> texRECT 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. Variants with integer samplers are only supported in gp4 and newer profiles.

> ## See Also

> texRECTbias, texRECTlod, texRECTproj