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
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
|
/* $Id: s_aalinetemp.h,v 1.10 2001/05/15 21:30:26 brianp Exp $ */
/*
* Mesa 3-D graphics library
* Version: 3.5
*
* Copyright (C) 1999-2001 Brian Paul 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, sublicense,
* 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 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 NONINFRINGEMENT. IN NO EVENT SHALL
* BRIAN PAUL 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.
*/
/*
* Antialiased line template.
*/
/*
* Function to render each fragment in the AA line.
*/
static void
NAME(plot)(GLcontext *ctx, const struct LineInfo *line,
struct pixel_buffer *pb, int ix, int iy)
{
const GLfloat fx = (GLfloat) ix;
const GLfloat fy = (GLfloat) iy;
const GLfloat coverage = compute_coveragef(line, ix, iy);
GLdepth z;
GLfloat fog;
#ifdef DO_RGBA
GLchan red, green, blue, alpha;
#else
GLint index;
#endif
GLchan specRed, specGreen, specBlue;
GLfloat tex[MAX_TEXTURE_UNITS][4], lambda[MAX_TEXTURE_UNITS];
if (coverage == 0.0)
return;
/*
* Compute Z, color, texture coords, fog for the fragment by
* solving the plane equations at (ix,iy).
*/
#ifdef DO_Z
z = (GLdepth) solve_plane(fx, fy, line->zPlane);
#else
z = 0.0;
#endif
#ifdef DO_FOG
fog = solve_plane(fx, fy, line->fPlane);
#else
fog = 0.0;
#endif
#ifdef DO_RGBA
red = solve_plane_chan(fx, fy, line->rPlane);
green = solve_plane_chan(fx, fy, line->gPlane);
blue = solve_plane_chan(fx, fy, line->bPlane);
alpha = solve_plane_chan(fx, fy, line->aPlane);
#endif
#ifdef DO_INDEX
index = (GLint) solve_plane(fx, fy, line->iPlane);
#else
(void) index;
#endif
#ifdef DO_SPEC
specRed = solve_plane_chan(fx, fy, line->srPlane);
specGreen = solve_plane_chan(fx, fy, line->sgPlane);
specBlue = solve_plane_chan(fx, fy, line->sbPlane);
#else
(void) specRed;
(void) specGreen;
(void) specBlue;
#endif
#ifdef DO_TEX
{
GLfloat invQ = solve_plane_recip(fx, fy, line->vPlane[0]);
tex[0][0] = solve_plane(fx, fy, line->sPlane[0]) * invQ;
tex[0][1] = solve_plane(fx, fy, line->tPlane[0]) * invQ;
tex[0][2] = solve_plane(fx, fy, line->uPlane[0]) * invQ;
lambda[0] = compute_lambda(line->sPlane[0], line->tPlane[0], invQ,
line->texWidth[0], line->texHeight[0]);
}
#elif defined(DO_MULTITEX)
{
GLuint unit;
for (unit = 0; unit < ctx->Const.MaxTextureUnits; unit++) {
if (ctx->Texture.Unit[unit]._ReallyEnabled) {
GLfloat invQ = solve_plane_recip(fx, fy, line->vPlane[unit]);
tex[unit][0] = solve_plane(fx, fy, line->sPlane[unit]) * invQ;
tex[unit][1] = solve_plane(fx, fy, line->tPlane[unit]) * invQ;
tex[unit][2] = solve_plane(fx, fy, line->uPlane[unit]) * invQ;
lambda[unit] = compute_lambda(line->sPlane[unit],
line->tPlane[unit], invQ,
line->texWidth[unit], line->texHeight[unit]);
}
}
}
#else
(void) tex[0][0];
(void) lambda[0];
#endif
PB_COVERAGE(pb, coverage);
#if defined(DO_MULTITEX)
#if defined(DO_SPEC)
PB_WRITE_MULTITEX_SPEC_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha,
specRed, specGreen, specBlue, tex);
#else
PB_WRITE_MULTITEX_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha, texcoords);
#endif
#elif defined(DO_TEX)
PB_WRITE_TEX_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha,
tex[0][0], tex[0][1], tex[0][2]);
#elif defined(DO_RGBA)
PB_WRITE_RGBA_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha);
#elif defined(DO_INDEX)
PB_WRITE_CI_PIXEL(pb, ix, iy, z, fog, index);
#endif
pb->haveCoverage = GL_TRUE;
PB_CHECK_FLUSH(ctx, pb);
}
/*
* Line setup
*/
static void
NAME(line)(GLcontext *ctx, const SWvertex *v0, const SWvertex *v1)
{
SWcontext *swrast = SWRAST_CONTEXT(ctx);
struct pixel_buffer *pb = SWRAST_CONTEXT(ctx)->PB;
GLfloat tStart, tEnd; /* segment start, end along line length */
GLboolean inSegment;
GLint iLen, i;
/* Init the LineInfo struct */
struct LineInfo line;
line.x0 = v0->win[0];
line.y0 = v0->win[1];
line.x1 = v1->win[0];
line.y1 = v1->win[1];
line.dx = line.x1 - line.x0;
line.dy = line.y1 - line.y0;
line.len = sqrt(line.dx * line.dx + line.dy * line.dy);
line.halfWidth = 0.5F * ctx->Line.Width;
if (line.len == 0.0)
return;
line.xAdj = line.dx / line.len * line.halfWidth;
line.yAdj = line.dy / line.len * line.halfWidth;
#ifdef DO_Z
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->win[2], v1->win[2], line.zPlane);
#endif
#ifdef DO_FOG
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->fog, v1->fog, line.fPlane);
#endif
#ifdef DO_RGBA
if (ctx->Light.ShadeModel == GL_SMOOTH) {
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->color[RCOMP], v1->color[RCOMP], line.rPlane);
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->color[GCOMP], v1->color[GCOMP], line.gPlane);
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->color[BCOMP], v1->color[BCOMP], line.bPlane);
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->color[ACOMP], v1->color[ACOMP], line.aPlane);
}
else {
constant_plane(v1->color[RCOMP], line.rPlane);
constant_plane(v1->color[GCOMP], line.gPlane);
constant_plane(v1->color[BCOMP], line.bPlane);
constant_plane(v1->color[ACOMP], line.aPlane);
}
#endif
#ifdef DO_SPEC
if (ctx->Light.ShadeModel == GL_SMOOTH) {
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->specular[RCOMP], v1->specular[RCOMP], line.srPlane);
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->specular[GCOMP], v1->specular[GCOMP], line.sgPlane);
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->specular[BCOMP], v1->specular[BCOMP], line.sbPlane);
}
else {
constant_plane(v1->specular[RCOMP], line.srPlane);
constant_plane(v1->specular[GCOMP], line.sgPlane);
constant_plane(v1->specular[BCOMP], line.sbPlane);
}
#endif
#ifdef DO_INDEX
if (ctx->Light.ShadeModel == GL_SMOOTH) {
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->index, v1->index, line.iPlane);
}
else {
constant_plane(v1->index, line.iPlane);
}
#endif
#ifdef DO_TEX
{
const struct gl_texture_object *obj = ctx->Texture.Unit[0]._Current;
const struct gl_texture_image *texImage = obj->Image[obj->BaseLevel];
const GLfloat invW0 = v0->win[3];
const GLfloat invW1 = v1->win[3];
const GLfloat s0 = v0->texcoord[0][0] * invW0;
const GLfloat s1 = v1->texcoord[0][0] * invW1;
const GLfloat t0 = v0->texcoord[0][1] * invW0;
const GLfloat t1 = v1->texcoord[0][1] * invW0;
const GLfloat r0 = v0->texcoord[0][2] * invW0;
const GLfloat r1 = v1->texcoord[0][2] * invW0;
const GLfloat q0 = v0->texcoord[0][3] * invW0;
const GLfloat q1 = v1->texcoord[0][3] * invW0;
compute_plane(line.x0, line.y0, line.x1, line.y1, s0, s1, line.sPlane[0]);
compute_plane(line.x0, line.y0, line.x1, line.y1, t0, t1, line.tPlane[0]);
compute_plane(line.x0, line.y0, line.x1, line.y1, r0, r1, line.uPlane[0]);
compute_plane(line.x0, line.y0, line.x1, line.y1, q0, q1, line.vPlane[0]);
line.texWidth[0] = (GLfloat) texImage->Width;
line.texHeight[0] = (GLfloat) texImage->Height;
}
#elif defined(DO_MULITEX)
{
GLuint u;
for (u = 0; u < ctx->Const.MaxTextureUnits; u++) {
if (ctx->Texture.Unit[u].ReallyEnabled) {
const struct gl_texture_object *obj = ctx->Texture.Unit[u].Current;
const struct gl_texture_image *texImage = obj->Image[obj->BaseLevel];
const GLfloat invW0 = v0->win[3];
const GLfloat invW1 = v1->win[3];
GLfloat (*texCoord)[4] = VB->TexCoordPtr[u]->data;
const GLfloat s0 = v0->texcoord[u][0] * invW0;
const GLfloat s1 = v1->texcoord[u][0] * invW1;
const GLfloat t0 = v0->texcoord[u][1] * invW0;
const GLfloat t1 = v1->texcoord[u][1] * invW0;
const GLfloat r0 = v0->texcoord[u][2] * invW0;
const GLfloat r1 = v1->texcoord[u][2] * invW0;
const GLfloat q0 = v0->texcoord[u][3] * invW0;
const GLfloat q1 = v1->texcoord[u][3] * invW0;
compute_plane(line.x0, line.y0, line.x1, line.y1, s0, s1, line.sPlane[u]);
compute_plane(line.x0, line.y0, line.x1, line.y1, t0, t1, line.tPlane[u]);
compute_plane(line.x0, line.y0, line.x1, line.y1, u0, u1, line.uPlane[u]);
compute_plane(line.x0, line.y0, line.x1, line.y1, v0, v1, line.vPlane[u]);
line.texWidth[u] = (GLfloat) texImage->Width;
line.texHeight[u] = (GLfloat) texImage->Height;
}
}
}
#endif
tStart = tEnd = 0.0;
inSegment = GL_FALSE;
iLen = (GLint) line.len;
if (ctx->Line.StippleFlag) {
for (i = 0; i < iLen; i++) {
const GLuint bit = (swrast->StippleCounter / ctx->Line.StippleFactor) & 0xf;
if ((1 << bit) & ctx->Line.StipplePattern) {
/* stipple bit is on */
const GLfloat t = (GLfloat) i / (GLfloat) line.len;
if (!inSegment) {
/* start new segment */
inSegment = GL_TRUE;
tStart = t;
}
else {
/* still in the segment, extend it */
tEnd = t;
}
}
else {
/* stipple bit is off */
if (inSegment && (tEnd > tStart)) {
/* draw the segment */
segment(ctx, &line, NAME(plot), pb, tStart, tEnd);
inSegment = GL_FALSE;
}
else {
/* still between segments, do nothing */
}
}
swrast->StippleCounter++;
}
if (inSegment) {
/* draw the final segment of the line */
segment(ctx, &line, NAME(plot), pb, tStart, 1.0F);
}
}
else {
/* non-stippled */
segment(ctx, &line, NAME(plot), pb, 0.0, 1.0);
}
}
#undef DO_Z
#undef DO_FOG
#undef DO_RGBA
#undef DO_INDEX
#undef DO_SPEC
#undef DO_TEX
#undef DO_MULTITEX
#undef NAME
|
