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
|
/*
* Mesa 3-D graphics library
* Version: 6.5
*
* Copyright (C) 1999-2005 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.
*/
#ifndef S_SPAN_H
#define S_SPAN_H
#include "mtypes.h"
#include "swrast.h"
/**
* \defgroup SpanFlags SPAN_*-flags
* Bitflags used for interpMask and arrayMask fields below to indicate
* which interpolant values and fragment arrays are in use, respectively.
*/
/*@{*/
#define SPAN_RGBA 0x001
#define SPAN_SPEC 0x002
#define SPAN_INDEX 0x004
#define SPAN_Z 0x008
#define SPAN_W 0x010
#define SPAN_FOG 0x020
#define SPAN_TEXTURE 0x040
#define SPAN_INT_TEXTURE 0x080
#define SPAN_LAMBDA 0x100
#define SPAN_COVERAGE 0x200
#define SPAN_FLAT 0x400 /**< flat shading? */
#define SPAN_XY 0x800
#define SPAN_MASK 0x1000
#define SPAN_VARYING 0x2000
/*@}*/
#if 0
/* alternate arrangement for code below */
struct arrays2 {
union {
GLubyte sz1[MAX_WIDTH][4]; /* primary color */
GLushort sz2[MAX_WIDTH][4];
GLfloat sz4[MAX_WIDTH][4];
} rgba;
union {
GLubyte sz1[MAX_WIDTH][4]; /* specular color and temp storage */
GLushort sz2[MAX_WIDTH][4];
GLfloat sz4[MAX_WIDTH][4];
} spec;
};
#endif
/**
* \sw_span_arrays
* \brief Arrays of fragment values.
*
* These will either be computed from the span x/xStep values or
* filled in by glDraw/CopyPixels, etc.
* These arrays are separated out of sw_span to conserve memory.
*/
typedef struct sw_span_arrays {
GLenum ChanType; /**< Color channel type, GL_UNSIGNED_BYTE, GL_FLOAT */
union {
struct {
GLubyte rgba[MAX_WIDTH][4]; /**< primary color */
GLubyte spec[MAX_WIDTH][4]; /**< specular color and temp storage */
} sz1;
struct {
GLushort rgba[MAX_WIDTH][4];
GLushort spec[MAX_WIDTH][4];
} sz2;
struct {
GLfloat rgba[MAX_WIDTH][4];
GLfloat spec[MAX_WIDTH][4];
} sz4;
} color;
/** XXX these are temporary fields, pointing into above color arrays */
GLchan (*rgba)[4];
GLchan (*spec)[4];
#if 0
/* XXX rearrange and unify these arrays to so that we can
* index all fragment inputs with the FRAG_ATTRIB_* values:
*/
GLfloat attribs[FRAG_ATTRIB_MAX][MAX_WIDTH][4];
/*OR*/
typedef GLfloat (*array4f)[4];
array4f attribs[FRAG_ATTRIB_MAX];
#endif
GLint x[MAX_WIDTH]; /**< fragment X coords */
GLint y[MAX_WIDTH]; /**< fragment Y coords */
GLuint z[MAX_WIDTH]; /**< fragment Z coords */
GLuint index[MAX_WIDTH]; /**< Color indexes */
GLfloat fog[MAX_WIDTH];
GLfloat texcoords[MAX_TEXTURE_COORD_UNITS][MAX_WIDTH][4];
GLfloat lambda[MAX_TEXTURE_COORD_UNITS][MAX_WIDTH];
GLfloat coverage[MAX_WIDTH]; /**< Fragment coverage for AA/smoothing */
GLfloat varying[MAX_VARYING][MAX_WIDTH][4]; /**< For shaders */
/** This mask indicates which fragments are alive or culled */
GLubyte mask[MAX_WIDTH];
} SWspanarrays;
/**
* The SWspan structure describes the colors, Z, fogcoord, texcoords,
* etc for either a horizontal run or an array of independent pixels.
* We can either specify a base/step to indicate interpolated values, or
* fill in explicit arrays of values. The interpMask and arrayMask bitfields
* indicate which attributes are active interpolants or arrays, respectively.
*
* It would be interesting to experiment with multiprocessor rasterization
* with this structure. The triangle rasterizer could simply emit a
* stream of these structures which would be consumed by one or more
* span-processing threads which could run in parallel.
*/
typedef struct sw_span {
GLint x, y;
/** Only need to process pixels between start <= i < end */
/** At this time, start is always zero. */
GLuint start, end;
/** This flag indicates that mask[] array is effectively filled with ones */
GLboolean writeAll;
/** either GL_POLYGON, GL_LINE, GL_POLYGON, GL_BITMAP */
GLenum primitive;
/** 0 = front-facing span, 1 = back-facing span (for two-sided stencil) */
GLuint facing;
/**
* This bitmask (of \link SpanFlags SPAN_* flags\endlink) indicates
* which of the x/xStep variables are relevant.
*/
GLbitfield interpMask;
/* For horizontal spans, step is the partial derivative wrt X.
* For lines, step is the delta from one fragment to the next.
*/
#if CHAN_TYPE == GL_FLOAT
GLfloat red, redStep;
GLfloat green, greenStep;
GLfloat blue, blueStep;
GLfloat alpha, alphaStep;
GLfloat specRed, specRedStep;
GLfloat specGreen, specGreenStep;
GLfloat specBlue, specBlueStep;
#else /* CHAN_TYPE == GL_UNSIGNED_BYTE or GL_UNSIGNED_SHORT */
GLfixed red, redStep;
GLfixed green, greenStep;
GLfixed blue, blueStep;
GLfixed alpha, alphaStep;
GLfixed specRed, specRedStep;
GLfixed specGreen, specGreenStep;
GLfixed specBlue, specBlueStep;
#endif
GLfixed index, indexStep;
GLfixed z, zStep; /* XXX z should probably be GLuint */
GLfloat fog, fogStep;
GLfloat tex[MAX_TEXTURE_COORD_UNITS][4]; /* s, t, r, q */
GLfloat texStepX[MAX_TEXTURE_COORD_UNITS][4];
GLfloat texStepY[MAX_TEXTURE_COORD_UNITS][4];
GLfixed intTex[2], intTexStep[2]; /* s, t only */
GLfloat var[MAX_VARYING][4];
GLfloat varStepX[MAX_VARYING][4];
GLfloat varStepY[MAX_VARYING][4];
/* partial derivatives wrt X and Y. */
GLfloat dzdx, dzdy;
GLfloat w, dwdx, dwdy;
GLfloat drdx, drdy;
GLfloat dgdx, dgdy;
GLfloat dbdx, dbdy;
GLfloat dadx, dady;
GLfloat dsrdx, dsrdy;
GLfloat dsgdx, dsgdy;
GLfloat dsbdx, dsbdy;
GLfloat dfogdx, dfogdy;
/**
* This bitmask (of \link SpanFlags SPAN_* flags\endlink) indicates
* which of the fragment arrays in the span_arrays struct are relevant.
*/
GLbitfield arrayMask;
/**
* We store the arrays of fragment values in a separate struct so
* that we can allocate sw_span structs on the stack without using
* a lot of memory. The span_arrays struct is about 1.4MB while the
* sw_span struct is only about 512 bytes.
*/
SWspanarrays *array;
} SWspan;
#define INIT_SPAN(S, PRIMITIVE, END, INTERP_MASK, ARRAY_MASK) \
do { \
(S).primitive = (PRIMITIVE); \
(S).interpMask = (INTERP_MASK); \
(S).arrayMask = (ARRAY_MASK); \
(S).start = 0; \
(S).end = (END); \
(S).facing = 0; \
(S).array = SWRAST_CONTEXT(ctx)->SpanArrays; \
} while (0)
extern void
_swrast_span_default_z( GLcontext *ctx, SWspan *span );
extern void
_swrast_span_interpolate_z( const GLcontext *ctx, SWspan *span );
extern void
_swrast_span_default_fog( GLcontext *ctx, SWspan *span );
extern void
_swrast_span_default_color( GLcontext *ctx, SWspan *span );
extern void
_swrast_span_default_texcoords( GLcontext *ctx, SWspan *span );
extern GLfloat
_swrast_compute_lambda(GLfloat dsdx, GLfloat dsdy, GLfloat dtdx, GLfloat dtdy,
GLfloat dqdx, GLfloat dqdy, GLfloat texW, GLfloat texH,
GLfloat s, GLfloat t, GLfloat q, GLfloat invQ);
extern void
_swrast_write_index_span( GLcontext *ctx, SWspan *span);
extern void
_swrast_write_rgba_span( GLcontext *ctx, SWspan *span);
extern void
_swrast_read_rgba_span(GLcontext *ctx, struct gl_renderbuffer *rb,
GLuint n, GLint x, GLint y, GLenum type, GLvoid *rgba);
extern void
_swrast_read_index_span( GLcontext *ctx, struct gl_renderbuffer *rb,
GLuint n, GLint x, GLint y, GLuint indx[] );
extern void
_swrast_get_values(GLcontext *ctx, struct gl_renderbuffer *rb,
GLuint count, const GLint x[], const GLint y[],
void *values, GLuint valueSize);
extern void
_swrast_put_row(GLcontext *ctx, struct gl_renderbuffer *rb,
GLuint count, GLint x, GLint y,
const GLvoid *values, GLuint valueSize);
extern void
_swrast_get_row(GLcontext *ctx, struct gl_renderbuffer *rb,
GLuint count, GLint x, GLint y,
GLvoid *values, GLuint valueSize);
extern void *
_swrast_get_dest_rgba(GLcontext *ctx, struct gl_renderbuffer *rb,
SWspan *span);
#endif
|
