static void
reset_stipple_counter(struct draw_stage *stage)
{
struct stipple_stage *stipple = stipple_stage(stage);
stipple->counter = 0;
stage->next->reset_stipple_counter( stage->next );
}
static void
stipple_reset_tri(struct draw_stage *stage, struct prim_header *header)
{
struct stipple_stage *stipple = stipple_stage(stage);
stipple->counter = 0;
stage->next->tri(stage->next, header);
}
static void
stipple_line(struct draw_stage *stage, struct prim_header *header)
{
struct stipple_stage *stipple = stipple_stage(stage);
struct vertex_header *v0 = header->v[0];
struct vertex_header *v1 = header->v[1];
const unsigned pos = draw_current_shader_position_output(stage->draw);
const float *pos0 = v0->data[pos];
const float *pos1 = v1->data[pos];
float start = 0;
bool state = 0;
float x0 = pos0[0];
float x1 = pos1[0];
float y0 = pos0[1];
float y1 = pos1[1];
float length;
int i;
if (stipple->smooth) {
float dx = x1 - x0;
float dy = y1 - y0;
length = sqrtf(dx*dx + dy*dy);
} else {
float dx = x0 > x1 ? x0 - x1 : x1 - x0;
float dy = y0 > y1 ? y0 - y1 : y1 - y0;
length = MAX2(dx, dy);
}
if (header->flags & DRAW_PIPE_RESET_STIPPLE)
stipple->counter = 0;
/* XXX ToDo: instead of iterating pixel-by-pixel, use a look-up table.
*/
for (i = 0; i < length; i++) {
bool result = stipple_test((int)stipple->counter + i,
(ushort)stipple->pattern, stipple->factor);
if (result != state) {
/* changing from "off" to "on" or vice versa */
if (state) {
if (start != i) {
/* finishing an "on" segment */
emit_segment(stage, header, start / length, i / length);
}
}
else {
/* starting an "on" segment */
start = (float)i;
}
state = result;
}
}
if (state && start < length)
emit_segment(stage, header, start / length, 1.0);
stipple->counter += length;
}
static void
stipple_first_line(struct draw_stage *stage,
struct prim_header *header)
{
struct stipple_stage *stipple = stipple_stage(stage);
struct draw_context *draw = stage->draw;
stipple->pattern = draw->rasterizer->line_stipple_pattern;
stipple->factor = draw->rasterizer->line_stipple_factor + 1;
stage->line = stipple_line;
stage->line( stage, header );
}
