diff options
| -rw-r--r-- | src/mesa/shader/prog_statevars.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/src/mesa/shader/prog_statevars.c b/src/mesa/shader/prog_statevars.c index 45352d30b5..eee4d2d925 100644 --- a/src/mesa/shader/prog_statevars.c +++ b/src/mesa/shader/prog_statevars.c @@ -253,7 +253,8 @@ _mesa_fetch_state(GLcontext *ctx, const gl_state_index state[], value[0] = ctx->Fog.Density; value[1] = ctx->Fog.Start; value[2] = ctx->Fog.End; - value[3] = 1.0F / (ctx->Fog.End - ctx->Fog.Start); + value[3] = (ctx->Fog.End == ctx->Fog.Start) + ? 1.0 : 1.0F / (ctx->Fog.End - ctx->Fog.Start); return; case STATE_CLIPPLANE: { @@ -424,8 +425,9 @@ _mesa_fetch_state(GLcontext *ctx, const gl_state_index state[], * exp: 2^-(density/ln(2) * fogcoord) * exp2: 2^-((density/(ln(2)^2) * fogcoord)^2) */ - value[0] = -1.0F / (ctx->Fog.End - ctx->Fog.Start); - value[1] = ctx->Fog.End / (ctx->Fog.End - ctx->Fog.Start); + value[0] = (ctx->Fog.End == ctx->Fog.Start) + ? 1.0 : -1.0F / (ctx->Fog.End - ctx->Fog.Start); + value[1] = ctx->Fog.End * -value[0]; value[2] = ctx->Fog.Density * ONE_DIV_LN2; value[3] = ctx->Fog.Density * ONE_DIV_SQRT_LN2; return; |