fog_world.nvv

游戏编程精华02－含有几十个游戏编程例子

#include "fog.h"


#define R_NORMAL r1
#define R_HALF_VECTOR r8
#define R_DIFFUSE r5
#define R_SPECULAR r6
#define R_POS_WORLD r9
#define R_TEMP r10

vs.1.0

; Transform position to clip space and output it
dp4 oPos.x, v0, c[CV_WORLDVIEWPROJ_0]
dp4 oPos.y, v0, c[CV_WORLDVIEWPROJ_1]
dp4 oPos.z, v0, c[CV_WORLDVIEWPROJ_2]
dp4 oPos.w, v0, c[CV_WORLDVIEWPROJ_3]

mov oT0.xy, v1

dp4 R_POS_WORLD.x, v0, c[CV_WORLD_0]
dp4 R_POS_WORLD.y, v0, c[CV_WORLD_1]
dp4 R_POS_WORLD.z, v0, c[CV_WORLD_2]
dp4 R_POS_WORLD.w, v0, c[CV_WORLD_3]

; Get height from floor
add R_TEMP.y, R_POS_WORLD.y, c[CV_FOG_SCALE].x
mul R_TEMP.y, R_TEMP.y, c[CV_FOG_SCALE].y
mov oT1.y, R_TEMP.y

; Get range
mov R_POS_WORLD.y, c[CV_ZERO].y
add R_POS_WORLD, R_POS_WORLD, -c[CV_WORLD_EYE];
dp3 R_POS_WORLD, R_POS_WORLD, R_POS_WORLD
rsq R_POS_WORLD.w, R_POS_WORLD.w
rcp R_POS_WORLD.w, R_POS_WORLD.w
mul oT1.x, R_POS_WORLD.w, c[CV_FOG_SCALE].z