brdf.nvv

来自「游戏编程精华02－含有几十个游戏编程例子」· NVV 代码 · 共 53 行

; v0  -- position
; v1  -- normal
; v2  -- tex coord
;
; c0-3   -- world/view/proj matrix
; c4     -- light vector
; c5    -- eye point
; c6	-- 1.0f

#include "constants.h"

#define srcPosition v0
#define srcNormal	v1
#define srcTexCoord	v2

#define destNormTex oT0
#define destLightTex oT1
#define destEyeTex oT2
#define destNormTex2 oT3

	vs.1.0


;transform position
	dp4 oPos.x, srcPosition, c[CV_WORLDVIEWPROJ_0]
	dp4 oPos.y, srcPosition, c[CV_WORLDVIEWPROJ_1]
	dp4 oPos.z, srcPosition, c[CV_WORLDVIEWPROJ_2]
	dp4 oPos.w, srcPosition, c[CV_WORLDVIEWPROJ_3]

; get light direction from vertex
; because this is a directional light.

	mov destLightTex, c[CVP_LIGHT_DIRECTION]

#ifdef MODULATE_COLOR
; get vertex position to eye position (-eye vector)
	sub	r0, c[CV_EYE_POSITION], srcPosition

; normalize the new vector
	dp3 r0.w, r0, r0
	rsq r0.w, r0.w
	mul destEyeTex, r0, r0.w					; destEyeTex coordinate now has normalized vector vertex->eye
	mov destEyeTex.w, c[CV_ONE]

#else
	mov	destEyeTex, srcNormal
#endif
	mov	destNormTex, srcNormal
	mov destNormTex2, srcNormal
	mov destNormTex2.w, c[CV_ONE]

	mov	oD0, c[CV_MATERIAL_COLOR]