mesa: glsl: implement exp() functions in terms of EXP asm instruction, not pow

This commit is contained in:
Brian Paul
2008-08-22 15:14:36 -06:00
parent 9e2b867b3f
commit 47d4b958cf

View File

@@ -473,32 +473,33 @@ vec4 pow(const vec4 a, const vec4 b)
float exp(const float a)
{
const float e = 2.71828;
__asm float_power __retVal, e, a;
// NOTE: log2(e) = 1.44269502
float t = a * 1.44269502;
__asm float_exp2 __retVal, t;
}
vec2 exp(const vec2 a)
{
const float e = 2.71828;
__asm float_power __retVal.x, e, a.x;
__asm float_power __retVal.y, e, a.y;
vec2 t = a * 1.44269502;
__asm float_exp2 __retVal.x, t.x;
__asm float_exp2 __retVal.y, t.y;
}
vec3 exp(const vec3 a)
{
const float e = 2.71828;
__asm float_power __retVal.x, e, a.x;
__asm float_power __retVal.y, e, a.y;
__asm float_power __retVal.z, e, a.z;
vec3 t = a * 1.44269502;
__asm float_exp2 __retVal.x, t.x;
__asm float_exp2 __retVal.y, t.y;
__asm float_exp2 __retVal.z, t.z;
}
vec4 exp(const vec4 a)
{
const float e = 2.71828;
__asm float_power __retVal.x, e, a.x;
__asm float_power __retVal.y, e, a.y;
__asm float_power __retVal.z, e, a.z;
__asm float_power __retVal.w, e, a.w;
vec4 t = a * 1.44269502;
__asm float_exp2 __retVal.x, t.x;
__asm float_exp2 __retVal.y, t.y;
__asm float_exp2 __retVal.z, t.z;
__asm float_exp2 __retVal.w, t.w;
}