texdp3 (Pixel Shader)

Performs a three-component dot product between data in the texture register number and the texture coordinate set corresponding to the destination register number.

Syntax

texdp3 (Pixel Shader) dest, src

Registers

dest

Destination register.

src

Input source register.

Remarks

Pixel shader versions	1_1	1_2	1_3	1_4	2_0	2_x	2_sw	3_0	3_sw
texdp3		x	x

Texture registers must use the following sequence.

 
tex    t(n)        // Define tn as a standard 3-vector (tn must be 
                   //   defined in some way before texdp3 uses it).
texdp3 t(m), t(n)  // where m > n
                   // Perform a three-component dot product between tn and 
                   //   the texture coordinate set m. The scalar result is
                   //   replicated to all components of t(m).
				

Here is more detail about how the dot product is accomplished.

The texdp3 (Pixel Shader) instruction performs a three-component dot product and replicates it to all four color channels.

t(m)RGBA = TextureCoordinates(stage m)UVW • t(n)RGB  

Instruction Information

Minimum operating systems	Windows 98