brdf.nvp

游戏编程精华02－含有几十个游戏编程例子

//
// Pixel shader - BRDF
//      This is actually minneart reflections
//
//

	#include "constants.h"

// Declare pixel shader version 1.0
	ps.1.0

	tex t0	
	texm3x2pad t1,t0_bx2		// dot normal with light vector (S coordinate)
	texm3x2tex t2,t0_bx2		// dot normal with eye vector (T coordinate)
	tex t3						// grab bump map normal 

#ifdef MODULATE_COLOR
	
	dp3_sat	r1, c[CVP_LIGHT_DIRECTION]_bx2, t3_bx2

	mul r0, r1, t2				// multiply in darkening limbs
	mul r0, r0, v0			// multiply by diffuse color
#else
	mov	r0,t2
#endif