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diff --git a/src/gallium/aux/draw/draw_wide_prims.c b/src/gallium/aux/draw/draw_wide_prims.c
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+/**************************************************************************
+ *
+ * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+ * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+
+/* Authors: Keith Whitwell <[email protected]>
+ */
+
+#include "pipe/p_util.h"
+#include "pipe/p_defines.h"
+#include "pipe/p_shader_tokens.h"
+#include "draw_private.h"
+
+
+struct wide_stage {
+ struct draw_stage stage;
+
+ float half_line_width;
+ float half_point_size;
+
+ uint texcoord_slot[PIPE_MAX_SHADER_OUTPUTS];
+ uint texcoord_mode[PIPE_MAX_SHADER_OUTPUTS];
+ uint num_texcoords;
+
+ int psize_slot;
+};
+
+
+
+static INLINE struct wide_stage *wide_stage( struct draw_stage *stage )
+{
+ return (struct wide_stage *)stage;
+}
+
+
+static void passthrough_point( struct draw_stage *stage,
+ struct prim_header *header )
+{
+ stage->next->point( stage->next, header );
+}
+
+static void passthrough_line( struct draw_stage *stage,
+ struct prim_header *header )
+{
+ stage->next->line(stage->next, header);
+}
+
+static void passthrough_tri( struct draw_stage *stage,
+ struct prim_header *header )
+{
+ stage->next->tri(stage->next, header);
+}
+
+
+/**
+ * Draw a wide line by drawing a quad (two triangles).
+ * XXX need to disable polygon stipple.
+ */
+static void wide_line( struct draw_stage *stage,
+ struct prim_header *header )
+{
+ const struct wide_stage *wide = wide_stage(stage);
+ const float half_width = wide->half_line_width;
+
+ struct prim_header tri;
+
+ struct vertex_header *v0 = dup_vert(stage, header->v[0], 0);
+ struct vertex_header *v1 = dup_vert(stage, header->v[0], 1);
+ struct vertex_header *v2 = dup_vert(stage, header->v[1], 2);
+ struct vertex_header *v3 = dup_vert(stage, header->v[1], 3);
+
+ float *pos0 = v0->data[0];
+ float *pos1 = v1->data[0];
+ float *pos2 = v2->data[0];
+ float *pos3 = v3->data[0];
+
+ const float dx = FABSF(pos0[0] - pos2[0]);
+ const float dy = FABSF(pos0[1] - pos2[1]);
+
+ /*
+ * Draw wide line as a quad (two tris) by "stretching" the line along
+ * X or Y.
+ * We need to tweak coords in several ways to be conformant here.
+ */
+
+ if (dx > dy) {
+ /* x-major line */
+ pos0[1] = pos0[1] - half_width - 0.25f;
+ pos1[1] = pos1[1] + half_width - 0.25f;
+ pos2[1] = pos2[1] - half_width - 0.25f;
+ pos3[1] = pos3[1] + half_width - 0.25f;
+ if (pos0[0] < pos2[0]) {
+ /* left to right line */
+ pos0[0] -= 0.5f;
+ pos1[0] -= 0.5f;
+ pos2[0] -= 0.5f;
+ pos3[0] -= 0.5f;
+ }
+ else {
+ /* right to left line */
+ pos0[0] += 0.5f;
+ pos1[0] += 0.5f;
+ pos2[0] += 0.5f;
+ pos3[0] += 0.5f;
+ }
+ }
+ else {
+ /* y-major line */
+ pos0[0] = pos0[0] - half_width + 0.25f;
+ pos1[0] = pos1[0] + half_width + 0.25f;
+ pos2[0] = pos2[0] - half_width + 0.25f;
+ pos3[0] = pos3[0] + half_width + 0.25f;
+ if (pos0[1] < pos2[1]) {
+ /* top to bottom line */
+ pos0[1] -= 0.5f;
+ pos1[1] -= 0.5f;
+ pos2[1] -= 0.5f;
+ pos3[1] -= 0.5f;
+ }
+ else {
+ /* bottom to top line */
+ pos0[1] += 0.5f;
+ pos1[1] += 0.5f;
+ pos2[1] += 0.5f;
+ pos3[1] += 0.5f;
+ }
+ }
+
+ tri.det = header->det; /* only the sign matters */
+ tri.v[0] = v0;
+ tri.v[1] = v2;
+ tri.v[2] = v3;
+ stage->next->tri( stage->next, &tri );
+
+ tri.v[0] = v0;
+ tri.v[1] = v3;
+ tri.v[2] = v1;
+ stage->next->tri( stage->next, &tri );
+}
+
+
+/**
+ * Draw a wide line by drawing a quad, using geometry which will
+ * fullfill GL's antialiased line requirements.
+ */
+static void wide_line_aa(struct draw_stage *stage,
+ struct prim_header *header)
+{
+ const struct wide_stage *wide = wide_stage(stage);
+ const float half_width = wide->half_line_width;
+ struct prim_header tri;
+ struct vertex_header *v[4];
+ float *pos;
+ float dx = header->v[1]->data[0][0] - header->v[0]->data[0][0];
+ float dy = header->v[1]->data[0][1] - header->v[0]->data[0][1];
+ const float len = (float) sqrt(dx * dx + dy * dy);
+ uint i;
+
+ dx = dx * half_width / len;
+ dy = dy * half_width / len;
+
+ /* allocate/dup new verts */
+ for (i = 0; i < 4; i++) {
+ v[i] = dup_vert(stage, header->v[i/2], i);
+ }
+
+ /*
+ * Quad for line from v0 to v1:
+ *
+ * 1 3
+ * +-------------------------+
+ * | |
+ * *v0 v1*
+ * | |
+ * +-------------------------+
+ * 0 2
+ */
+
+ pos = v[0]->data[0];
+ pos[0] += dy;
+ pos[1] -= dx;
+
+ pos = v[1]->data[0];
+ pos[0] -= dy;
+ pos[1] += dx;
+
+ pos = v[2]->data[0];
+ pos[0] += dy;
+ pos[1] -= dx;
+
+ pos = v[3]->data[0];
+ pos[0] -= dy;
+ pos[1] += dx;
+
+ tri.det = header->det; /* only the sign matters */
+
+ tri.v[0] = v[2]; tri.v[1] = v[1]; tri.v[2] = v[0];
+ stage->next->tri( stage->next, &tri );
+
+ tri.v[0] = v[3]; tri.v[1] = v[1]; tri.v[2] = v[2];
+ stage->next->tri( stage->next, &tri );
+
+}
+
+
+/**
+ * Set the vertex texcoords for sprite mode.
+ * Coords may be left untouched or set to a right-side-up or upside-down
+ * orientation.
+ */
+static void set_texcoords(const struct wide_stage *wide,
+ struct vertex_header *v, const float tc[4])
+{
+ uint i;
+ for (i = 0; i < wide->num_texcoords; i++) {
+ if (wide->texcoord_mode[i] != PIPE_SPRITE_COORD_NONE) {
+ uint j = wide->texcoord_slot[i];
+ v->data[j][0] = tc[0];
+ if (wide->texcoord_mode[i] == PIPE_SPRITE_COORD_LOWER_LEFT)
+ v->data[j][1] = 1.0f - tc[1];
+ else
+ v->data[j][1] = tc[1];
+ v->data[j][2] = tc[2];
+ v->data[j][3] = tc[3];
+ }
+ }
+}
+
+
+/* If there are lots of sprite points (and why wouldn't there be?) it
+ * would probably be more sensible to change hardware setup to
+ * optimize this rather than doing the whole thing in software like
+ * this.
+ */
+static void wide_point( struct draw_stage *stage,
+ struct prim_header *header )
+{
+ const struct wide_stage *wide = wide_stage(stage);
+ const boolean sprite = (boolean) stage->draw->rasterizer->point_sprite;
+ float half_size;
+ float left_adj, right_adj;
+
+ struct prim_header tri;
+
+ /* four dups of original vertex */
+ struct vertex_header *v0 = dup_vert(stage, header->v[0], 0);
+ struct vertex_header *v1 = dup_vert(stage, header->v[0], 1);
+ struct vertex_header *v2 = dup_vert(stage, header->v[0], 2);
+ struct vertex_header *v3 = dup_vert(stage, header->v[0], 3);
+
+ float *pos0 = v0->data[0];
+ float *pos1 = v1->data[0];
+ float *pos2 = v2->data[0];
+ float *pos3 = v3->data[0];
+
+ /* point size is either per-vertex or fixed size */
+ if (wide->psize_slot >= 0) {
+ half_size = 0.5f * header->v[0]->data[wide->psize_slot][0];
+ }
+ else {
+ half_size = wide->half_point_size;
+ }
+
+ left_adj = -half_size + 0.25f;
+ right_adj = half_size + 0.25f;
+
+ pos0[0] += left_adj;
+ pos0[1] -= half_size;
+
+ pos1[0] += left_adj;
+ pos1[1] += half_size;
+
+ pos2[0] += right_adj;
+ pos2[1] -= half_size;
+
+ pos3[0] += right_adj;
+ pos3[1] += half_size;
+
+ if (sprite) {
+ static const float tex00[4] = { 0, 0, 0, 1 };
+ static const float tex01[4] = { 0, 1, 0, 1 };
+ static const float tex11[4] = { 1, 1, 0, 1 };
+ static const float tex10[4] = { 1, 0, 0, 1 };
+ set_texcoords( wide, v0, tex00 );
+ set_texcoords( wide, v1, tex01 );
+ set_texcoords( wide, v2, tex10 );
+ set_texcoords( wide, v3, tex11 );
+ }
+
+ tri.det = header->det; /* only the sign matters */
+ tri.v[0] = v0;
+ tri.v[1] = v2;
+ tri.v[2] = v3;
+ stage->next->tri( stage->next, &tri );
+
+ tri.v[0] = v0;
+ tri.v[1] = v3;
+ tri.v[2] = v1;
+ stage->next->tri( stage->next, &tri );
+}
+
+
+static void wide_first_point( struct draw_stage *stage,
+ struct prim_header *header )
+{
+ struct wide_stage *wide = wide_stage(stage);
+ struct draw_context *draw = stage->draw;
+
+ wide->half_point_size = 0.5f * draw->rasterizer->point_size;
+
+ if (draw->rasterizer->point_size != 1.0) {
+ stage->point = wide_point;
+ }
+ else {
+ stage->point = passthrough_point;
+ }
+
+ if (draw->rasterizer->point_sprite) {
+ /* find vertex shader texcoord outputs */
+ const struct draw_vertex_shader *vs = draw->vertex_shader;
+ uint i, j = 0;
+ for (i = 0; i < vs->state->num_outputs; i++) {
+ if (vs->state->output_semantic_name[i] == TGSI_SEMANTIC_GENERIC) {
+ wide->texcoord_slot[j] = i;
+ wide->texcoord_mode[j] = draw->rasterizer->sprite_coord_mode[j];
+ j++;
+ }
+ }
+ wide->num_texcoords = j;
+ }
+
+ wide->psize_slot = -1;
+
+ if (draw->rasterizer->point_size_per_vertex) {
+ /* find PSIZ vertex output */
+ const struct draw_vertex_shader *vs = draw->vertex_shader;
+ uint i;
+ for (i = 0; i < vs->state->num_outputs; i++) {
+ if (vs->state->output_semantic_name[i] == TGSI_SEMANTIC_PSIZE) {
+ wide->psize_slot = i;
+ break;
+ }
+ }
+ }
+
+ stage->point( stage, header );
+}
+
+
+
+static void wide_first_line( struct draw_stage *stage,
+ struct prim_header *header )
+{
+ struct wide_stage *wide = wide_stage(stage);
+ struct draw_context *draw = stage->draw;
+
+ wide->half_line_width = 0.5f * draw->rasterizer->line_width;
+
+ if (draw->rasterizer->line_width != 1.0) {
+ if (draw->rasterizer->line_smooth)
+ wide->stage.line = wide_line_aa;
+ else
+ wide->stage.line = wide_line;
+ }
+ else {
+ wide->stage.line = passthrough_line;
+ }
+
+ stage->line( stage, header );
+}
+
+
+static void wide_flush( struct draw_stage *stage, unsigned flags )
+{
+ stage->line = wide_first_line;
+ stage->point = wide_first_point;
+ stage->next->flush( stage->next, flags );
+}
+
+
+static void wide_reset_stipple_counter( struct draw_stage *stage )
+{
+ stage->next->reset_stipple_counter( stage->next );
+}
+
+
+static void wide_destroy( struct draw_stage *stage )
+{
+ draw_free_temp_verts( stage );
+ FREE( stage );
+}
+
+
+struct draw_stage *draw_wide_stage( struct draw_context *draw )
+{
+ struct wide_stage *wide = CALLOC_STRUCT(wide_stage);
+
+ draw_alloc_temp_verts( &wide->stage, 4 );
+
+ wide->stage.draw = draw;
+ wide->stage.next = NULL;
+ wide->stage.point = wide_first_point;
+ wide->stage.line = wide_first_line;
+ wide->stage.tri = passthrough_tri;
+ wide->stage.flush = wide_flush;
+ wide->stage.reset_stipple_counter = wide_reset_stipple_counter;
+ wide->stage.destroy = wide_destroy;
+
+ return &wide->stage;
+}