static void build_fog( struct tnl_program *p )
{
struct ureg fog = register_output(p, VARYING_SLOT_FOGC);
struct ureg input;
if (p->state->fog_source_is_depth) {
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);
}
emit_op1(p, OPCODE_MOV, fog, WRITEMASK_YZW, get_identity_param(p));
}
/**
* Point size attenuation computation.
*/
static void build_atten_pointsize( struct tnl_program *p )
{
struct ureg eye = get_eye_position_z(p);
struct ureg state_size = register_param1(p, STATE_POINT_SIZE);
struct ureg state_attenuation = register_param1(p, STATE_POINT_ATTENUATION);
struct ureg out = register_output(p, VERT_RESULT_PSIZ);
struct ureg ut = get_temp(p);
/* dist = |eyez| */
emit_op1(p, OPCODE_ABS, ut, WRITEMASK_Y, swizzle1(eye, Z));
/* p1 + dist * (p2 + dist * p3); */
emit_op3(p, OPCODE_MAD, ut, WRITEMASK_X, swizzle1(ut, Y),
swizzle1(state_attenuation, Z), swizzle1(state_attenuation, Y));
emit_op3(p, OPCODE_MAD, ut, WRITEMASK_X, swizzle1(ut, Y),
ut, swizzle1(state_attenuation, X));
/* 1 / sqrt(factor) */
emit_op1(p, OPCODE_RSQ, ut, WRITEMASK_X, ut );
#if 0
/* out = pointSize / sqrt(factor) */
emit_op2(p, OPCODE_MUL, out, WRITEMASK_X, ut, state_size);
#else
/* this is a good place to clamp the point size since there's likely
* no hardware registers to clamp point size at rasterization time.
*/
emit_op2(p, OPCODE_MUL, ut, WRITEMASK_X, ut, state_size);
emit_op2(p, OPCODE_MAX, ut, WRITEMASK_X, ut, swizzle1(state_size, Y));
emit_op2(p, OPCODE_MIN, out, WRITEMASK_X, ut, swizzle1(state_size, Z));
#endif
release_temp(p, ut);
}
static void build_fog( struct tnl_program *p )
{
struct ureg fog = register_output(p, VERT_RESULT_FOGC);
struct ureg input;
if (p->state->fog_source_is_depth) {
input = get_eye_position_z(p);
}
else {
input = swizzle1(register_input(p, VERT_ATTRIB_FOG), X);
}
/* 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));
}
