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authorBrian Paul <[email protected]>2004-12-15 01:07:52 +0000
committerBrian Paul <[email protected]>2004-12-15 01:07:52 +0000
commit55481b3a2977179f47b6d8cec0700e0991dba462 (patch)
tree8e2bc21358a3b5dd3a7cfa9d5af92b64303e3532 /src/mesa/shader
parent244adeb639cf13c531bcce78734b911fc19b943d (diff)
tweaks to the LIT instructions
Diffstat (limited to 'src/mesa/shader')
-rw-r--r--src/mesa/shader/nvvertexec.c13
1 files changed, 4 insertions, 9 deletions
diff --git a/src/mesa/shader/nvvertexec.c b/src/mesa/shader/nvvertexec.c
index 79929f14a5a..269c4c93d8c 100644
--- a/src/mesa/shader/nvvertexec.c
+++ b/src/mesa/shader/nvvertexec.c
@@ -412,17 +412,12 @@ _mesa_exec_vertex_program(GLcontext *ctx, const struct vertex_program *program)
break;
case VP_OPCODE_LIT:
{
- const GLfloat epsilon = 1.0e-5F; /* XXX fix? */
+ const GLfloat epsilon = 1.0F / 256.0F; /* per NV spec */
GLfloat t[4], lit[4];
fetch_vector4( &inst->SrcReg[0], state, t );
- if (t[3] < -(128.0F - epsilon))
- t[3] = - (128.0F - epsilon);
- else if (t[3] > 128.0F - epsilon)
- t[3] = 128.0F - epsilon;
- if (t[0] < 0.0)
- t[0] = 0.0;
- if (t[1] < 0.0)
- t[1] = 0.0;
+ t[0] = MAX2(t[0], 0.0F);
+ t[1] = MAX2(t[1], 0.0F);
+ t[3] = CLAMP(t[3], -(128.0F - epsilon), (128.0F - epsilon));
lit[0] = 1.0;
lit[1] = t[0];
lit[2] = (t[0] > 0.0) ? (GLfloat) exp(t[3] * log(t[1])) : 0.0F;