1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
|
/**************************************************************************
*
* 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 <keith@tungstengraphics.com>
*/
#include "pipe/p_context.h"
#include "pipe/p_defines.h"
#include "pipe/p_shader_tokens.h"
#include "util/u_math.h"
#include "util/u_memory.h"
#include "draw_private.h"
#include "draw_pipe.h"
struct wideline_stage {
struct draw_stage stage;
float half_line_width;
};
static INLINE struct wideline_stage *wideline_stage( struct draw_stage *stage )
{
return (struct wideline_stage *)stage;
}
/**
* Draw a wide line by drawing a quad (two triangles).
*/
static void wideline_line( struct draw_stage *stage,
struct prim_header *header )
{
/*const struct wideline_stage *wide = wideline_stage(stage);*/
const unsigned pos = draw_current_shader_position_output(stage->draw);
const float half_width = 0.5f * stage->draw->rasterizer->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[pos];
float *pos1 = v1->data[pos];
float *pos2 = v2->data[pos];
float *pos3 = v3->data[pos];
const float dx = fabsf(pos0[0] - pos2[0]);
const float dy = fabsf(pos0[1] - pos2[1]);
const boolean gl_rasterization_rules =
stage->draw->rasterizer->gl_rasterization_rules;
/* small tweak to meet GL specification */
const float bias = gl_rasterization_rules ? 0.125f : 0.0f;
/*
* 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 - bias;
pos1[1] = pos1[1] + half_width - bias;
pos2[1] = pos2[1] - half_width - bias;
pos3[1] = pos3[1] + half_width - bias;
if (gl_rasterization_rules) {
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 + bias;
pos1[0] = pos1[0] + half_width + bias;
pos2[0] = pos2[0] - half_width + bias;
pos3[0] = pos3[0] + half_width + bias;
if (gl_rasterization_rules) {
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 );
}
static void wideline_first_line( struct draw_stage *stage,
struct prim_header *header )
{
struct draw_context *draw = stage->draw;
struct pipe_context *pipe = draw->pipe;
const struct pipe_rasterizer_state *rast = draw->rasterizer;
void *r;
/* Disable triangle culling, stippling, unfilled mode etc. */
r = draw_get_rasterizer_no_cull(draw, rast->scissor, rast->flatshade);
draw->suspend_flushing = TRUE;
pipe->bind_rasterizer_state(pipe, r);
draw->suspend_flushing = FALSE;
stage->line = wideline_line;
wideline_line(stage, header);
}
static void wideline_flush( struct draw_stage *stage, unsigned flags )
{
struct draw_context *draw = stage->draw;
struct pipe_context *pipe = draw->pipe;
stage->line = wideline_first_line;
stage->next->flush( stage->next, flags );
/* restore original rasterizer state */
if (draw->rast_handle) {
draw->suspend_flushing = TRUE;
pipe->bind_rasterizer_state(pipe, draw->rast_handle);
draw->suspend_flushing = FALSE;
}
}
static void wideline_reset_stipple_counter( struct draw_stage *stage )
{
stage->next->reset_stipple_counter( stage->next );
}
static void wideline_destroy( struct draw_stage *stage )
{
draw_free_temp_verts( stage );
FREE( stage );
}
struct draw_stage *draw_wide_line_stage( struct draw_context *draw )
{
struct wideline_stage *wide = CALLOC_STRUCT(wideline_stage);
if (wide == NULL)
goto fail;
wide->stage.draw = draw;
wide->stage.name = "wide-line";
wide->stage.next = NULL;
wide->stage.point = draw_pipe_passthrough_point;
wide->stage.line = wideline_first_line;
wide->stage.tri = draw_pipe_passthrough_tri;
wide->stage.flush = wideline_flush;
wide->stage.reset_stipple_counter = wideline_reset_stipple_counter;
wide->stage.destroy = wideline_destroy;
if (!draw_alloc_temp_verts( &wide->stage, 4 ))
goto fail;
return &wide->stage;
fail:
if (wide)
wide->stage.destroy( &wide->stage );
return NULL;
}
|
