This is all that is needed to implement NV_fog_distance on programmable hardware. --- src/mesa/main/ffvertex_prog.c | 40 ++++++++++++++++++++++++++++++++++++---- 1 files changed, 36 insertions(+), 4 deletions(-)
diff --git a/src/mesa/main/ffvertex_prog.c b/src/mesa/main/ffvertex_prog.c index 2d2485c..fc7b01a 100644 --- a/src/mesa/main/ffvertex_prog.c +++ b/src/mesa/main/ffvertex_prog.c @@ -61,6 +61,7 @@ struct state_key { unsigned rescale_normals:1; unsigned fog_source_is_depth:1; + unsigned fog_distance_mode:2; unsigned separate_specular:1; unsigned point_attenuated:1; unsigned point_array:1; @@ -108,7 +109,19 @@ static GLuint translate_texgen( GLboolean enabled, GLenum mode ) } } +#define FDM_EYE_RADIAL 0 +#define FDM_EYE_PLANE 1 +#define FDM_EYE_PLANE_ABS 2 +static GLuint translate_fog_distance_mode( GLenum mode ) +{ + switch (mode) { + case GL_EYE_RADIAL_NV: return FDM_EYE_RADIAL; + case GL_EYE_PLANE: return FDM_EYE_PLANE; + default: /* shouldn't happen; fall through to a sensible default */ + case GL_EYE_PLANE_ABSOLUTE_NV: return FDM_EYE_PLANE_ABS; + } +} static GLboolean check_active_shininess( struct gl_context *ctx, const struct state_key *key, @@ -205,8 +218,10 @@ static void make_state_key( struct gl_context *ctx, struct state_key *key ) if (ctx->Transform.RescaleNormals) key->rescale_normals = 1; - if (ctx->Fog.FogCoordinateSource == GL_FRAGMENT_DEPTH_EXT) + if (ctx->Fog.FogCoordinateSource == GL_FRAGMENT_DEPTH_EXT) { key->fog_source_is_depth = 1; + key->fog_distance_mode = translate_fog_distance_mode(ctx->Fog.FogDistanceMode); + } if (ctx->Point._Attenuated) key->point_attenuated = 1; @@ -1308,14 +1323,31 @@ static void build_fog( struct tnl_program *p ) struct ureg input; if (p->state->fog_source_is_depth) { - input = get_eye_position_z(p); + + switch (p->state->fog_distance_mode) { + case FDM_EYE_RADIAL: /* Z = sqrt(Xe*Xe + Ye*Ye + Ze*Ze) */ + input = get_eye_position(p); + emit_op2(p, OPCODE_DP3, fog, WRITEMASK_X, input, input); + emit_op1(p, OPCODE_RSQ, fog, WRITEMASK_X, fog); + emit_op1(p, OPCODE_RCP, fog, WRITEMASK_X, fog); + break; + case FDM_EYE_PLANE: /* Z = Ze */ + input = get_eye_position_z(p); + emit_op1(p, OPCODE_MOV, fog, WRITEMASK_X, input); + break; + case FDM_EYE_PLANE_ABS: /* Z = abs(Ze) */ + input = get_eye_position_z(p); + emit_op1(p, OPCODE_ABS, fog, WRITEMASK_X, input); + break; + default: assert(0); break; /* can't happen */ + } + } else { input = swizzle1(register_input(p, VERT_ATTRIB_FOG), X); + emit_op1(p, OPCODE_ABS, fog, WRITEMASK_X, input); } - /* result.fog = {abs(f),0,0,1}; */ - emit_op1(p, OPCODE_ABS, fog, WRITEMASK_X, input); emit_op1(p, OPCODE_MOV, fog, WRITEMASK_YZW, get_identity_param(p)); } -- 1.7.6.2 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev