/*
* Clip points but ignore the first 4 (xy) clip planes.
* (Because the generated clip mask is completely unaffacted by guard band,
* we still need to manually evaluate the x/y planes if they are outside
* the guard band and not just outside the vp.)
*/
static void
clip_point_guard_xy( struct draw_stage *stage,
struct prim_header *header )
{
unsigned clipmask = header->v[0]->clipmask;
if ((clipmask & 0xffffffff) == 0)
stage->next->point(stage->next, header);
else if ((clipmask & 0xfffffff0) == 0) {
while (clipmask) {
const unsigned plane_idx = ffs(clipmask)-1;
clipmask &= ~(1 << plane_idx); /* turn off this plane's bit */
/* TODO: this should really do proper guardband clipping,
* currently just throw out infs/nans.
* Also note that vertices with negative w values MUST be tossed
* out (not sure if proper guardband clipping would do this
* automatically). These would usually be captured by depth clip
* too but this can be disabled.
*/
if (header->v[0]->clip[3] <= 0.0f ||
util_is_inf_or_nan(header->v[0]->clip[0]) ||
util_is_inf_or_nan(header->v[0]->clip[1]))
return;
}
stage->next->point(stage->next, header);
}
}
/*#define DEBUG_INPUTS 1*/
static void draw_fetch_gs_input(struct draw_geometry_shader *shader,
unsigned *indices,
unsigned num_vertices,
unsigned prim_idx)
{
struct tgsi_exec_machine *machine = shader->machine;
unsigned slot, vs_slot, i;
unsigned input_vertex_stride = shader->input_vertex_stride;
const float (*input_ptr)[4];
input_ptr = shader->input;
for (i = 0; i < num_vertices; ++i) {
const float (*input)[4];
#if DEBUG_INPUTS
debug_printf("%d) vertex index = %d (prim idx = %d)\n",
i, indices[i], prim_idx);
#endif
input = (const float (*)[4])(
(const char *)input_ptr + (indices[i] * input_vertex_stride));
for (slot = 0, vs_slot = 0; slot < shader->info.num_inputs; ++slot) {
unsigned idx = i * TGSI_EXEC_MAX_INPUT_ATTRIBS + slot;
if (shader->info.input_semantic_name[slot] == TGSI_SEMANTIC_PRIMID) {
machine->Inputs[idx].xyzw[0].f[prim_idx] =
(float)shader->in_prim_idx;
machine->Inputs[idx].xyzw[1].f[prim_idx] =
(float)shader->in_prim_idx;
machine->Inputs[idx].xyzw[2].f[prim_idx] =
(float)shader->in_prim_idx;
machine->Inputs[idx].xyzw[3].f[prim_idx] =
(float)shader->in_prim_idx;
} else {
#if DEBUG_INPUTS
debug_printf("\tSlot = %d, vs_slot = %d, idx = %d:\n",
slot, vs_slot, idx);
#endif
#if 1
assert(!util_is_inf_or_nan(input[vs_slot][0]));
assert(!util_is_inf_or_nan(input[vs_slot][1]));
assert(!util_is_inf_or_nan(input[vs_slot][2]));
assert(!util_is_inf_or_nan(input[vs_slot][3]));
#endif
machine->Inputs[idx].xyzw[0].f[prim_idx] = input[vs_slot][0];
machine->Inputs[idx].xyzw[1].f[prim_idx] = input[vs_slot][1];
machine->Inputs[idx].xyzw[2].f[prim_idx] = input[vs_slot][2];
machine->Inputs[idx].xyzw[3].f[prim_idx] = input[vs_slot][3];
#if DEBUG_INPUTS
debug_printf("\t\t%f %f %f %f\n",
machine->Inputs[idx].xyzw[0].f[prim_idx],
machine->Inputs[idx].xyzw[1].f[prim_idx],
machine->Inputs[idx].xyzw[2].f[prim_idx],
machine->Inputs[idx].xyzw[3].f[prim_idx]);
#endif
++vs_slot;
}
}
}
}
static void print_vertex(const struct setup_context *setup,
const float (*v)[4])
{
int i;
debug_printf(" Vertex: (%p)\n", (void *) v);
for (i = 0; i < setup->nr_vertex_attrs; i++) {
debug_printf(" %d: %f %f %f %f\n", i,
v[i][0], v[i][1], v[i][2], v[i][3]);
if (util_is_inf_or_nan(v[i][0])) {
debug_printf(" NaN!\n");
}
}
}
/*#define DEBUG_OUTPUTS 1*/
static void
tgsi_fetch_gs_outputs(struct draw_geometry_shader *shader,
unsigned num_primitives,
float (**p_output)[4])
{
struct tgsi_exec_machine *machine = shader->machine;
unsigned prim_idx, j, slot;
unsigned current_idx = 0;
float (*output)[4];
output = *p_output;
/* Unswizzle all output results.
*/
for (prim_idx = 0; prim_idx < num_primitives; ++prim_idx) {
unsigned num_verts_per_prim = machine->Primitives[prim_idx];
shader->primitive_lengths[prim_idx + shader->emitted_primitives] =
machine->Primitives[prim_idx];
shader->emitted_vertices += num_verts_per_prim;
for (j = 0; j < num_verts_per_prim; j++, current_idx++) {
int idx = current_idx * shader->info.num_outputs;
#ifdef DEBUG_OUTPUTS
debug_printf("%d) Output vert:\n", idx / shader->info.num_outputs);
#endif
for (slot = 0; slot < shader->info.num_outputs; slot++) {
output[slot][0] = machine->Outputs[idx + slot].xyzw[0].f[0];
output[slot][1] = machine->Outputs[idx + slot].xyzw[1].f[0];
output[slot][2] = machine->Outputs[idx + slot].xyzw[2].f[0];
output[slot][3] = machine->Outputs[idx + slot].xyzw[3].f[0];
#ifdef DEBUG_OUTPUTS
debug_printf("\t%d: %f %f %f %f\n", slot,
output[slot][0],
output[slot][1],
output[slot][2],
output[slot][3]);
#endif
debug_assert(!util_is_inf_or_nan(output[slot][0]));
}
output = (float (*)[4])((char *)output + shader->vertex_size);
}
}
*p_output = output;
shader->emitted_primitives += num_primitives;
}
static void
llvm_fetch_gs_input(struct draw_geometry_shader *shader,
unsigned *indices,
unsigned num_vertices,
unsigned prim_idx)
{
unsigned slot, i;
int vs_slot;
unsigned input_vertex_stride = shader->input_vertex_stride;
const float (*input_ptr)[4];
float (*input_data)[6][PIPE_MAX_SHADER_INPUTS][TGSI_NUM_CHANNELS][TGSI_NUM_CHANNELS] = &shader->gs_input->data;
shader->llvm_prim_ids[shader->fetched_prim_count] =
shader->in_prim_idx;
input_ptr = shader->input;
for (i = 0; i < num_vertices; ++i) {
const float (*input)[4];
#if DEBUG_INPUTS
debug_printf("%d) vertex index = %d (prim idx = %d)\n",
i, indices[i], prim_idx);
#endif
input = (const float (*)[4])(
(const char *)input_ptr + (indices[i] * input_vertex_stride));
for (slot = 0, vs_slot = 0; slot < shader->info.num_inputs; ++slot) {
if (shader->info.input_semantic_name[slot] == TGSI_SEMANTIC_PRIMID) {
/* skip. we handle system values through gallivm */
} else {
vs_slot = draw_gs_get_input_index(
shader->info.input_semantic_name[slot],
shader->info.input_semantic_index[slot],
shader->input_info);
if (vs_slot < 0) {
debug_printf("VS/GS signature mismatch!\n");
(*input_data)[i][slot][0][prim_idx] = 0;
(*input_data)[i][slot][1][prim_idx] = 0;
(*input_data)[i][slot][2][prim_idx] = 0;
(*input_data)[i][slot][3][prim_idx] = 0;
} else {
#if DEBUG_INPUTS
debug_printf("\tSlot = %d, vs_slot = %d, i = %d:\n",
slot, vs_slot, i);
assert(!util_is_inf_or_nan(input[vs_slot][0]));
assert(!util_is_inf_or_nan(input[vs_slot][1]));
assert(!util_is_inf_or_nan(input[vs_slot][2]));
assert(!util_is_inf_or_nan(input[vs_slot][3]));
#endif
(*input_data)[i][slot][0][prim_idx] = input[vs_slot][0];
(*input_data)[i][slot][1][prim_idx] = input[vs_slot][1];
(*input_data)[i][slot][2][prim_idx] = input[vs_slot][2];
(*input_data)[i][slot][3][prim_idx] = input[vs_slot][3];
#if DEBUG_INPUTS
debug_printf("\t\t%f %f %f %f\n",
(*input_data)[i][slot][0][prim_idx],
(*input_data)[i][slot][1][prim_idx],
(*input_data)[i][slot][2][prim_idx],
(*input_data)[i][slot][3][prim_idx]);
#endif
++vs_slot;
}
}
}
}
}
/**
* Compute the setup->coef[] array dadx, dady, a0 values.
* Must be called after setup->vmin,vmax are initialized.
*/
static boolean
setup_line_coefficients(struct setup_context *setup,
const float (*v0)[4],
const float (*v1)[4])
{
struct softpipe_context *softpipe = setup->softpipe;
const struct tgsi_shader_info *fsInfo = &setup->softpipe->fs_variant->info;
const struct sp_setup_info *sinfo = &softpipe->setup_info;
uint fragSlot;
float area;
float v[2];
assert(sinfo->valid);
/* use setup->vmin, vmax to point to vertices */
if (softpipe->rasterizer->flatshade_first)
setup->vprovoke = v0;
else
setup->vprovoke = v1;
setup->vmin = v0;
setup->vmax = v1;
setup->emaj.dx = setup->vmax[0][0] - setup->vmin[0][0];
setup->emaj.dy = setup->vmax[0][1] - setup->vmin[0][1];
/* NOTE: this is not really area but something proportional to it */
area = setup->emaj.dx * setup->emaj.dx + setup->emaj.dy * setup->emaj.dy;
if (area == 0.0f || util_is_inf_or_nan(area))
return FALSE;
setup->oneoverarea = 1.0f / area;
/* z and w are done by linear interpolation:
*/
v[0] = setup->vmin[0][2];
v[1] = setup->vmax[0][2];
line_linear_coeff(setup, &setup->posCoef, 2, v);
v[0] = setup->vmin[0][3];
v[1] = setup->vmax[0][3];
line_linear_coeff(setup, &setup->posCoef, 3, v);
/* setup interpolation for all the remaining attributes:
*/
for (fragSlot = 0; fragSlot < fsInfo->num_inputs; fragSlot++) {
const uint vertSlot = sinfo->attrib[fragSlot].src_index;
uint j;
switch (sinfo->attrib[fragSlot].interp) {
case SP_INTERP_CONSTANT:
for (j = 0; j < TGSI_NUM_CHANNELS; j++)
const_coeff(setup, &setup->coef[fragSlot], vertSlot, j);
break;
case SP_INTERP_LINEAR:
for (j = 0; j < TGSI_NUM_CHANNELS; j++) {
line_apply_cylindrical_wrap(setup->vmin[vertSlot][j],
setup->vmax[vertSlot][j],
fsInfo->input_cylindrical_wrap[fragSlot] & (1 << j),
v);
line_linear_coeff(setup, &setup->coef[fragSlot], j, v);
}
break;
case SP_INTERP_PERSPECTIVE:
for (j = 0; j < TGSI_NUM_CHANNELS; j++) {
line_apply_cylindrical_wrap(setup->vmin[vertSlot][j],
setup->vmax[vertSlot][j],
fsInfo->input_cylindrical_wrap[fragSlot] & (1 << j),
v);
line_persp_coeff(setup, &setup->coef[fragSlot], j, v);
}
break;
case SP_INTERP_POS:
setup_fragcoord_coeff(setup, fragSlot);
break;
default:
assert(0);
}
if (fsInfo->input_semantic_name[fragSlot] == TGSI_SEMANTIC_FACE) {
/* convert 0 to 1.0 and 1 to -1.0 */
setup->coef[fragSlot].a0[0] = setup->facing * -2.0f + 1.0f;
setup->coef[fragSlot].dadx[0] = 0.0;
setup->coef[fragSlot].dady[0] = 0.0;
}
}
return TRUE;
}
/**
* Sort the vertices from top to bottom order, setting up the triangle
* edge fields (ebot, emaj, etop).
* \return FALSE if coords are inf/nan (cull the tri), TRUE otherwise
*/
static boolean
setup_sort_vertices(struct setup_context *setup,
float det,
const float (*v0)[4],
const float (*v1)[4],
const float (*v2)[4])
{
if (setup->softpipe->rasterizer->flatshade_first)
setup->vprovoke = v0;
else
setup->vprovoke = v2;
/* determine bottom to top order of vertices */
{
float y0 = v0[0][1];
float y1 = v1[0][1];
float y2 = v2[0][1];
if (y0 <= y1) {
if (y1 <= y2) {
/* y0<=y1<=y2 */
setup->vmin = v0;
setup->vmid = v1;
setup->vmax = v2;
}
else if (y2 <= y0) {
/* y2<=y0<=y1 */
setup->vmin = v2;
setup->vmid = v0;
setup->vmax = v1;
}
else {
/* y0<=y2<=y1 */
setup->vmin = v0;
setup->vmid = v2;
setup->vmax = v1;
}
}
else {
if (y0 <= y2) {
/* y1<=y0<=y2 */
setup->vmin = v1;
setup->vmid = v0;
setup->vmax = v2;
}
else if (y2 <= y1) {
/* y2<=y1<=y0 */
setup->vmin = v2;
setup->vmid = v1;
setup->vmax = v0;
}
else {
/* y1<=y2<=y0 */
setup->vmin = v1;
setup->vmid = v2;
setup->vmax = v0;
}
}
}
setup->ebot.dx = setup->vmid[0][0] - setup->vmin[0][0];
setup->ebot.dy = setup->vmid[0][1] - setup->vmin[0][1];
setup->emaj.dx = setup->vmax[0][0] - setup->vmin[0][0];
setup->emaj.dy = setup->vmax[0][1] - setup->vmin[0][1];
setup->etop.dx = setup->vmax[0][0] - setup->vmid[0][0];
setup->etop.dy = setup->vmax[0][1] - setup->vmid[0][1];
/*
* Compute triangle's area. Use 1/area to compute partial
* derivatives of attributes later.
*
* The area will be the same as prim->det, but the sign may be
* different depending on how the vertices get sorted above.
*
* To determine whether the primitive is front or back facing we
* use the prim->det value because its sign is correct.
*/
{
const float area = (setup->emaj.dx * setup->ebot.dy -
setup->ebot.dx * setup->emaj.dy);
setup->oneoverarea = 1.0f / area;
/*
debug_printf("%s one-over-area %f area %f det %f\n",
__FUNCTION__, setup->oneoverarea, area, det );
*/
if (util_is_inf_or_nan(setup->oneoverarea))
return FALSE;
}
/* We need to know if this is a front or back-facing triangle for:
* - the GLSL gl_FrontFacing fragment attribute (bool)
* - two-sided stencil test
* 0 = front-facing, 1 = back-facing
*/
setup->facing =
((det < 0.0) ^
(setup->softpipe->rasterizer->front_ccw));
{
unsigned face = setup->facing == 0 ? PIPE_FACE_FRONT : PIPE_FACE_BACK;
if (face & setup->cull_face)
return FALSE;
}
return TRUE;
}
/**
* Compute the setup->coef[] array dadx, dady, a0 values.
* Must be called after setup->vmin,vmax are initialized.
*/
static INLINE boolean
setup_line_coefficients(struct setup_context *setup,
const float (*v0)[4],
const float (*v1)[4])
{
struct softpipe_context *softpipe = setup->softpipe;
const struct sp_fragment_shader *spfs = softpipe->fs;
const struct vertex_info *vinfo = softpipe_get_vertex_info(softpipe);
uint fragSlot;
float area;
/* use setup->vmin, vmax to point to vertices */
if (softpipe->rasterizer->flatshade_first)
setup->vprovoke = v0;
else
setup->vprovoke = v1;
setup->vmin = v0;
setup->vmax = v1;
setup->emaj.dx = setup->vmax[0][0] - setup->vmin[0][0];
setup->emaj.dy = setup->vmax[0][1] - setup->vmin[0][1];
/* NOTE: this is not really area but something proportional to it */
area = setup->emaj.dx * setup->emaj.dx + setup->emaj.dy * setup->emaj.dy;
if (area == 0.0f || util_is_inf_or_nan(area))
return FALSE;
setup->oneoverarea = 1.0f / area;
/* z and w are done by linear interpolation:
*/
line_linear_coeff(setup, &setup->posCoef, 0, 2);
line_linear_coeff(setup, &setup->posCoef, 0, 3);
/* setup interpolation for all the remaining attributes:
*/
for (fragSlot = 0; fragSlot < spfs->info.num_inputs; fragSlot++) {
const uint vertSlot = vinfo->attrib[fragSlot].src_index;
uint j;
switch (vinfo->attrib[fragSlot].interp_mode) {
case INTERP_CONSTANT:
for (j = 0; j < NUM_CHANNELS; j++)
const_coeff(setup, &setup->coef[fragSlot], vertSlot, j);
break;
case INTERP_LINEAR:
for (j = 0; j < NUM_CHANNELS; j++)
line_linear_coeff(setup, &setup->coef[fragSlot], vertSlot, j);
break;
case INTERP_PERSPECTIVE:
for (j = 0; j < NUM_CHANNELS; j++)
line_persp_coeff(setup, &setup->coef[fragSlot], vertSlot, j);
break;
case INTERP_POS:
setup_fragcoord_coeff(setup, fragSlot);
break;
default:
assert(0);
}
if (spfs->info.input_semantic_name[fragSlot] == TGSI_SEMANTIC_FACE) {
setup->coef[fragSlot].a0[0] = 1.0f - setup->facing;
setup->coef[fragSlot].dadx[0] = 0.0;
setup->coef[fragSlot].dady[0] = 0.0;
}
}
return TRUE;
}
/**
* Sort the vertices from top to bottom order, setting up the triangle
* edge fields (ebot, emaj, etop).
* \return FALSE if coords are inf/nan (cull the tri), TRUE otherwise
*/
static boolean setup_sort_vertices( struct setup_context *setup,
float det,
const float (*v0)[4],
const float (*v1)[4],
const float (*v2)[4] )
{
setup->vprovoke = v2;
/* determine bottom to top order of vertices */
{
float y0 = v0[0][1];
float y1 = v1[0][1];
float y2 = v2[0][1];
if (y0 <= y1) {
if (y1 <= y2) {
/* y0<=y1<=y2 */
setup->vmin = v0;
setup->vmid = v1;
setup->vmax = v2;
}
else if (y2 <= y0) {
/* y2<=y0<=y1 */
setup->vmin = v2;
setup->vmid = v0;
setup->vmax = v1;
}
else {
/* y0<=y2<=y1 */
setup->vmin = v0;
setup->vmid = v2;
setup->vmax = v1;
}
}
else {
if (y0 <= y2) {
/* y1<=y0<=y2 */
setup->vmin = v1;
setup->vmid = v0;
setup->vmax = v2;
}
else if (y2 <= y1) {
/* y2<=y1<=y0 */
setup->vmin = v2;
setup->vmid = v1;
setup->vmax = v0;
}
else {
/* y1<=y2<=y0 */
setup->vmin = v1;
setup->vmid = v2;
setup->vmax = v0;
}
}
}
setup->ebot.dx = setup->vmid[0][0] - setup->vmin[0][0];
setup->ebot.dy = setup->vmid[0][1] - setup->vmin[0][1];
setup->emaj.dx = setup->vmax[0][0] - setup->vmin[0][0];
setup->emaj.dy = setup->vmax[0][1] - setup->vmin[0][1];
setup->etop.dx = setup->vmax[0][0] - setup->vmid[0][0];
setup->etop.dy = setup->vmax[0][1] - setup->vmid[0][1];
/*
* Compute triangle's area. Use 1/area to compute partial
* derivatives of attributes later.
*
* The area will be the same as prim->det, but the sign may be
* different depending on how the vertices get sorted above.
*
* To determine whether the primitive is front or back facing we
* use the prim->det value because its sign is correct.
*/
{
const float area = (setup->emaj.dx * setup->ebot.dy -
setup->ebot.dx * setup->emaj.dy);
setup->oneoverarea = 1.0f / area;
/*
debug_printf("%s one-over-area %f area %f det %f\n",
__FUNCTION__, setup->oneoverarea, area, det );
*/
if (util_is_inf_or_nan(setup->oneoverarea))
return FALSE;
}
/* We need to know if this is a front or back-facing triangle for:
* - the GLSL gl_FrontFacing fragment attribute (bool)
* - two-sided stencil test
*/
setup->facing =
((det > 0.0) ^
(setup->softpipe->rasterizer->front_winding == PIPE_WINDING_CW));
/* Prepare pixel offset for rasterisation:
* - pixel center (0.5, 0.5) for GL, or
* - assume (0.0, 0.0) for other APIs.
*/
if (setup->softpipe->rasterizer->gl_rasterization_rules) {
setup->pixel_offset = 0.5f;
} else {
setup->pixel_offset = 0.0f;
}
return TRUE;
}
/* Clip a line against the viewport and user clip planes.
*/
static void
do_clip_line( struct draw_stage *stage,
struct prim_header *header,
unsigned clipmask )
{
const struct clip_stage *clipper = clip_stage( stage );
struct vertex_header *v0 = header->v[0];
struct vertex_header *v1 = header->v[1];
float t0 = 0.0F;
float t1 = 0.0F;
struct prim_header newprim;
int viewport_index = draw_viewport_index(clipper->stage.draw, v0);
while (clipmask) {
const unsigned plane_idx = ffs(clipmask)-1;
const float dp0 = getclipdist(clipper, v0, plane_idx);
const float dp1 = getclipdist(clipper, v1, plane_idx);
if (util_is_inf_or_nan(dp0) || util_is_inf_or_nan(dp1))
return; //discard nan
if (dp1 < 0.0F) {
float t = dp1 / (dp1 - dp0);
t1 = MAX2(t1, t);
}
if (dp0 < 0.0F) {
float t = dp0 / (dp0 - dp1);
t0 = MAX2(t0, t);
}
if (t0 + t1 >= 1.0F)
return; /* discard */
clipmask &= ~(1 << plane_idx); /* turn off this plane's bit */
}
if (v0->clipmask) {
interp( clipper, stage->tmp[0], t0, v0, v1, viewport_index );
if (stage->draw->rasterizer->flatshade_first) {
copy_flat(stage, stage->tmp[0], v0); /* copy v0 color to tmp[0] */
}
else {
copy_flat(stage, stage->tmp[0], v1); /* copy v1 color to tmp[0] */
}
newprim.v[0] = stage->tmp[0];
}
else {
newprim.v[0] = v0;
}
if (v1->clipmask) {
interp( clipper, stage->tmp[1], t1, v1, v0, viewport_index );
if (stage->draw->rasterizer->flatshade_first) {
copy_flat(stage, stage->tmp[1], v0); /* copy v0 color to tmp[1] */
}
else {
copy_flat(stage, stage->tmp[1], v1); /* copy v1 color to tmp[1] */
}
newprim.v[1] = stage->tmp[1];
}
else {
newprim.v[1] = v1;
}
stage->next->line( stage->next, &newprim );
}
/* Clip a triangle against the viewport and user clip planes.
*/
static void
do_clip_tri( struct draw_stage *stage,
struct prim_header *header,
unsigned clipmask )
{
struct clip_stage *clipper = clip_stage( stage );
struct vertex_header *a[MAX_CLIPPED_VERTICES];
struct vertex_header *b[MAX_CLIPPED_VERTICES];
struct vertex_header **inlist = a;
struct vertex_header **outlist = b;
unsigned tmpnr = 0;
unsigned n = 3;
unsigned i;
boolean aEdges[MAX_CLIPPED_VERTICES];
boolean bEdges[MAX_CLIPPED_VERTICES];
boolean *inEdges = aEdges;
boolean *outEdges = bEdges;
int viewport_index = 0;
inlist[0] = header->v[0];
inlist[1] = header->v[1];
inlist[2] = header->v[2];
viewport_index = draw_viewport_index(clipper->stage.draw, inlist[0]);
if (DEBUG_CLIP) {
const float *v0 = header->v[0]->clip;
const float *v1 = header->v[1]->clip;
const float *v2 = header->v[2]->clip;
debug_printf("Clip triangle:\n");
debug_printf(" %f, %f, %f, %f\n", v0[0], v0[1], v0[2], v0[3]);
debug_printf(" %f, %f, %f, %f\n", v1[0], v1[1], v1[2], v1[3]);
debug_printf(" %f, %f, %f, %f\n", v2[0], v2[1], v2[2], v2[3]);
}
/*
* Note: at this point we can't just use the per-vertex edge flags.
* We have to observe the edge flag bits set in header->flags which
* were set during primitive decomposition. Put those flags into
* an edge flags array which parallels the vertex array.
* Later, in the 'unfilled' pipeline stage we'll draw the edge if both
* the header.flags bit is set AND the per-vertex edgeflag field is set.
*/
inEdges[0] = !!(header->flags & DRAW_PIPE_EDGE_FLAG_0);
inEdges[1] = !!(header->flags & DRAW_PIPE_EDGE_FLAG_1);
inEdges[2] = !!(header->flags & DRAW_PIPE_EDGE_FLAG_2);
while (clipmask && n >= 3) {
const unsigned plane_idx = ffs(clipmask)-1;
const boolean is_user_clip_plane = plane_idx >= 6;
struct vertex_header *vert_prev = inlist[0];
boolean *edge_prev = &inEdges[0];
float dp_prev;
unsigned outcount = 0;
dp_prev = getclipdist(clipper, vert_prev, plane_idx);
clipmask &= ~(1<<plane_idx);
if (util_is_inf_or_nan(dp_prev))
return; //discard nan
assert(n < MAX_CLIPPED_VERTICES);
if (n >= MAX_CLIPPED_VERTICES)
return;
inlist[n] = inlist[0]; /* prevent rotation of vertices */
inEdges[n] = inEdges[0];
for (i = 1; i <= n; i++) {
struct vertex_header *vert = inlist[i];
boolean *edge = &inEdges[i];
float dp = getclipdist(clipper, vert, plane_idx);
if (util_is_inf_or_nan(dp))
return; //discard nan
if (dp_prev >= 0.0f) {
assert(outcount < MAX_CLIPPED_VERTICES);
if (outcount >= MAX_CLIPPED_VERTICES)
return;
outEdges[outcount] = *edge_prev;
outlist[outcount++] = vert_prev;
}
if (DIFFERENT_SIGNS(dp, dp_prev)) {
struct vertex_header *new_vert;
boolean *new_edge;
assert(tmpnr < MAX_CLIPPED_VERTICES + 1);
if (tmpnr >= MAX_CLIPPED_VERTICES + 1)
return;
new_vert = clipper->stage.tmp[tmpnr++];
assert(outcount < MAX_CLIPPED_VERTICES);
if (outcount >= MAX_CLIPPED_VERTICES)
return;
new_edge = &outEdges[outcount];
outlist[outcount++] = new_vert;
if (dp < 0.0f) {
/* Going out of bounds. Avoid division by zero as we
* know dp != dp_prev from DIFFERENT_SIGNS, above.
*/
float t = dp / (dp - dp_prev);
interp( clipper, new_vert, t, vert, vert_prev, viewport_index );
/* Whether or not to set edge flag for the new vert depends
* on whether it's a user-defined clipping plane. We're
* copying NVIDIA's behaviour here.
*/
if (is_user_clip_plane) {
/* we want to see an edge along the clip plane */
*new_edge = TRUE;
new_vert->edgeflag = TRUE;
}
else {
/* we don't want to see an edge along the frustum clip plane */
*new_edge = *edge_prev;
new_vert->edgeflag = FALSE;
}
}
else {
/* Coming back in.
*/
float t = dp_prev / (dp_prev - dp);
interp( clipper, new_vert, t, vert_prev, vert, viewport_index );
/* Copy starting vert's edgeflag:
*/
new_vert->edgeflag = vert_prev->edgeflag;
*new_edge = *edge_prev;
}
}
vert_prev = vert;
edge_prev = edge;
dp_prev = dp;
}
/* swap in/out lists */
{
struct vertex_header **tmp = inlist;
inlist = outlist;
outlist = tmp;
n = outcount;
}
{
boolean *tmp = inEdges;
inEdges = outEdges;
outEdges = tmp;
}
}
/* If flat-shading, copy provoking vertex color to polygon vertex[0]
*/
if (n >= 3) {
if (clipper->num_flat_attribs) {
if (stage->draw->rasterizer->flatshade_first) {
if (inlist[0] != header->v[0]) {
assert(tmpnr < MAX_CLIPPED_VERTICES + 1);
if (tmpnr >= MAX_CLIPPED_VERTICES + 1)
return;
inlist[0] = dup_vert(stage, inlist[0], tmpnr++);
copy_flat(stage, inlist[0], header->v[0]);
}
}
else {
if (inlist[0] != header->v[2]) {
assert(tmpnr < MAX_CLIPPED_VERTICES + 1);
if (tmpnr >= MAX_CLIPPED_VERTICES + 1)
return;
inlist[0] = dup_vert(stage, inlist[0], tmpnr++);
copy_flat(stage, inlist[0], header->v[2]);
}
}
}
/* Emit the polygon as triangles to the setup stage:
*/
emit_poly( stage, inlist, inEdges, n, header );
}
}
