summaryrefslogtreecommitdiff
path: root/src/mesa/swrast/s_aalinetemp.h
blob: 64767a3a5644d4475f5768b926cfbcad666fa324 (plain)
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
/*
 * Mesa 3-D graphics library
 *
 * Copyright (C) 1999-2007  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
 * THE AUTHORS OR COPYRIGHT HOLDERS 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.
 * \param ix  - integer fragment window X coordiante
 * \param iy  - integer fragment window Y coordiante
 */
static void
NAME(plot)(struct gl_context *ctx, struct LineInfo *line, int ix, int iy)
{
   const SWcontext *swrast = SWRAST_CONTEXT(ctx);
   const GLfloat fx = (GLfloat) ix;
   const GLfloat fy = (GLfloat) iy;
   const GLfloat coverage = compute_coveragef(line, ix, iy);
   const GLuint i = line->span.end;

   (void) swrast;

   if (coverage == 0.0F)
      return;

   line->span.end++;
   line->span.array->coverage[i] = coverage;
   line->span.array->x[i] = ix;
   line->span.array->y[i] = iy;

   /*
    * Compute Z, color, texture coords, fog for the fragment by
    * solving the plane equations at (ix,iy).
    */
#ifdef DO_Z
   line->span.array->z[i] = (GLuint) solve_plane(fx, fy, line->zPlane);
#endif
   line->span.array->rgba[i][RCOMP] = solve_plane_chan(fx, fy, line->rPlane);
   line->span.array->rgba[i][GCOMP] = solve_plane_chan(fx, fy, line->gPlane);
   line->span.array->rgba[i][BCOMP] = solve_plane_chan(fx, fy, line->bPlane);
   line->span.array->rgba[i][ACOMP] = solve_plane_chan(fx, fy, line->aPlane);
#if defined(DO_ATTRIBS)
   ATTRIB_LOOP_BEGIN
      GLfloat (*attribArray)[4] = line->span.array->attribs[attr];
      if (attr >= VARYING_SLOT_TEX0 && attr < VARYING_SLOT_VAR0
          && !_swrast_use_fragment_program(ctx)) {
         /* texcoord w/ divide by Q */
         const GLuint unit = attr - VARYING_SLOT_TEX0;
         const GLfloat invQ = solve_plane_recip(fx, fy, line->attrPlane[attr][3]);
         GLuint c;
         for (c = 0; c < 3; c++) {
            attribArray[i][c] = solve_plane(fx, fy, line->attrPlane[attr][c]) * invQ;
         }
         line->span.array->lambda[unit][i]
            = compute_lambda(line->attrPlane[attr][0],
                             line->attrPlane[attr][1], invQ,
                             line->texWidth[attr], line->texHeight[attr]);
      }
      else {
         /* non-texture attrib */
         const GLfloat invW = solve_plane_recip(fx, fy, line->wPlane);
         GLuint c;
         for (c = 0; c < 4; c++) {
            attribArray[i][c] = solve_plane(fx, fy, line->attrPlane[attr][c]) * invW;
         }
      }
   ATTRIB_LOOP_END
#endif

   if (line->span.end == SWRAST_MAX_WIDTH) {
      _swrast_write_rgba_span(ctx, &(line->span));
      line->span.end = 0; /* reset counter */
   }
}



/*
 * Line setup
 */
static void
NAME(line)(struct gl_context *ctx, const SWvertex *v0, const SWvertex *v1)
{
   SWcontext *swrast = SWRAST_CONTEXT(ctx);
   GLfloat tStart, tEnd;   /* segment start, end along line length */
   GLboolean inSegment;
   GLint iLen, i;

   /* Init the LineInfo struct */
   struct LineInfo line;
   line.x0 = v0->attrib[VARYING_SLOT_POS][0];
   line.y0 = v0->attrib[VARYING_SLOT_POS][1];
   line.x1 = v1->attrib[VARYING_SLOT_POS][0];
   line.y1 = v1->attrib[VARYING_SLOT_POS][1];
   line.dx = line.x1 - line.x0;
   line.dy = line.y1 - line.y0;
   line.len = sqrtf(line.dx * line.dx + line.dy * line.dy);
   line.halfWidth = 0.5F * CLAMP(ctx->Line.Width,
                                 ctx->Const.MinLineWidthAA,
                                 ctx->Const.MaxLineWidthAA);

   if (line.len == 0.0F || IS_INF_OR_NAN(line.len))
      return;

   INIT_SPAN(line.span, GL_LINE);
   line.span.arrayMask = SPAN_XY | SPAN_COVERAGE;
   line.span.facing = swrast->PointLineFacing;
   line.xAdj = line.dx / line.len * line.halfWidth;
   line.yAdj = line.dy / line.len * line.halfWidth;

#ifdef DO_Z
   line.span.arrayMask |= SPAN_Z;
   compute_plane(line.x0, line.y0, line.x1, line.y1,
                 v0->attrib[VARYING_SLOT_POS][2], v1->attrib[VARYING_SLOT_POS][2], line.zPlane);
#endif
   line.span.arrayMask |= SPAN_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);
   }
#if defined(DO_ATTRIBS)
   {
      const GLfloat invW0 = v0->attrib[VARYING_SLOT_POS][3];
      const GLfloat invW1 = v1->attrib[VARYING_SLOT_POS][3];
      line.span.arrayMask |= SPAN_LAMBDA;
      compute_plane(line.x0, line.y0, line.x1, line.y1, invW0, invW1, line.wPlane);
      ATTRIB_LOOP_BEGIN
         GLuint c;
         if (swrast->_InterpMode[attr] == GL_FLAT) {
            for (c = 0; c < 4; c++) {
               constant_plane(v1->attrib[attr][c], line.attrPlane[attr][c]);
            }
         }
         else {
            for (c = 0; c < 4; c++) {
               const GLfloat a0 = v0->attrib[attr][c] * invW0;
               const GLfloat a1 = v1->attrib[attr][c] * invW1;
               compute_plane(line.x0, line.y0, line.x1, line.y1, a0, a1,
                             line.attrPlane[attr][c]);
            }
         }
         line.span.arrayAttribs |= BITFIELD64_BIT(attr);
         if (attr >= VARYING_SLOT_TEX0 && attr < VARYING_SLOT_VAR0) {
            const GLuint u = attr - VARYING_SLOT_TEX0;
            const struct gl_texture_object *obj = ctx->Texture.Unit[u]._Current;
            if (obj) {
               const struct gl_texture_image *texImage =
                  _mesa_base_tex_image(obj);
               line.texWidth[attr]  = (GLfloat) texImage->Width;
               line.texHeight[attr] = (GLfloat) texImage->Height;
            }
         }
      ATTRIB_LOOP_END
   }
#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), 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), tStart, 1.0F);
      }
   }
   else {
      /* non-stippled */
      segment(ctx, &line, NAME(plot), 0.0, 1.0);
   }

   _swrast_write_rgba_span(ctx, &(line.span));
}




#undef DO_Z
#undef DO_ATTRIBS
#undef NAME