From db0f050582e73d64b7d260275ff0c1eed912b35d Mon Sep 17 00:00:00 2001 From: Roland Scheidegger Date: Wed, 3 Oct 2007 22:20:44 +0200 Subject: minor fog calc cleanup --- src/mesa/tnl/t_vb_fog.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) (limited to 'src/mesa/tnl/t_vb_fog.c') diff --git a/src/mesa/tnl/t_vb_fog.c b/src/mesa/tnl/t_vb_fog.c index f6518500d8..d8bca3820b 100644 --- a/src/mesa/tnl/t_vb_fog.c +++ b/src/mesa/tnl/t_vb_fog.c @@ -41,7 +41,6 @@ struct fog_stage_data { GLvector4f fogcoord; /* has actual storage allocated */ - GLvector4f input; /* points into VB->EyePtr Z values */ }; #define FOG_STAGE_DATA(stage) ((struct fog_stage_data *)stage->privatePtr) @@ -91,7 +90,8 @@ init_static_data( void ) * evaluating the GL_LINEAR, GL_EXP or GL_EXP2 fog function. * Fog coordinates are distances from the eye (typically between the * near and far clip plane distances). - * Note the fog (eye Z) coords may be negative so we use ABS(z) below. + * Note that fogcoords may be negative, if eye z is source absolute + * value must be taken earlier. * Fog blend factors are in the range [0,1]. */ static void @@ -169,13 +169,10 @@ run_fog_stage(GLcontext *ctx, struct tnl_pipeline_stage *stage) */ input = &store->fogcoord; - /* NOTE: negate plane here so we get positive fog coords! */ - /* NOTE2: this doesn't always work (tests/fog - all frag depth fog - coords will be negative). */ - plane[0] = -m[2]; - plane[1] = -m[6]; - plane[2] = -m[10]; - plane[3] = -m[14]; + plane[0] = m[2]; + plane[1] = m[6]; + plane[2] = m[10]; + plane[3] = m[14]; /* Full eye coords weren't required, just calculate the * eye Z values. */ @@ -189,12 +186,12 @@ run_fog_stage(GLcontext *ctx, struct tnl_pipeline_stage *stage) NOTE should avoid going through array twice */ coord = input->start; for (i = 0; i < input->count; i++) { - input->data[i][0] = FABSF(*coord); + *coord = FABSF(*coord); STRIDE_F(coord, input->stride); } } else { - /* fog coordinates = eye Z coordinates (use ABS later) */ + /* fog coordinates = eye Z coordinates - need to copy for ABS */ input = &store->fogcoord; if (VB->EyePtr->size < 2) @@ -249,7 +246,6 @@ alloc_fog_data(GLcontext *ctx, struct tnl_pipeline_stage *stage) return GL_FALSE; _mesa_vector4f_alloc( &store->fogcoord, 0, tnl->vb.Size, 32 ); - _mesa_vector4f_init( &store->input, 0, NULL ); if (!inited) init_static_data(); -- cgit v1.2.3