diff options
Diffstat (limited to 'src/mesa/swrast/s_nvfragprog.c')
| -rw-r--r-- | src/mesa/swrast/s_nvfragprog.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/src/mesa/swrast/s_nvfragprog.c b/src/mesa/swrast/s_nvfragprog.c index 88a6593aff4..d083f83645d 100644 --- a/src/mesa/swrast/s_nvfragprog.c +++ b/src/mesa/swrast/s_nvfragprog.c @@ -1,6 +1,6 @@ /* * Mesa 3-D graphics library - * Version: 6.1 + * Version: 6.3 * * Copyright (C) 1999-2004 Brian Paul All Rights Reserved. * @@ -805,14 +805,16 @@ execute_program( GLcontext *ctx, break; case FP_OPCODE_LIT: { + const GLfloat epsilon = 1.0F / 256.0F; /* from NV VP spec */ GLfloat a[4], result[4]; fetch_vector4( ctx, &inst->SrcReg[0], machine, program, a ); - if (a[0] < 0.0F) - a[0] = 0.0F; - if (a[1] < 0.0F) - a[1] = 0.0F; + a[0] = MAX2(a[0], 0.0F); + a[1] = MAX2(a[1], 0.0F); + /* XXX ARB version clamps a[3], NV version doesn't */ + a[3] = CLAMP(a[3], -(128.0F - epsilon), (128.0F - epsilon)); result[0] = 1.0F; result[1] = a[0]; + /* XXX we could probably just use pow() here */ result[2] = (a[0] > 0.0F) ? (GLfloat) exp(a[3] * log(a[1])) : 0.0F; result[3] = 1.0F; store_vector4( inst, machine, result ); |