1 /*
2 * Mesa 3-D graphics library
3 *
4 * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included
14 * in all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25
26 /**
27 * \file swrast/s_context.h
28 * \brief Software rasterization context and private types.
29 * \author Keith Whitwell <keithw@vmware.com>
30 */
31
32 /**
33 * \mainpage swrast module
34 *
35 * This module, software rasterization, contains the software fallback
36 * routines for drawing points, lines, triangles, bitmaps and images.
37 * All rendering boils down to writing spans (arrays) of pixels with
38 * particular colors. The span-writing routines must be implemented
39 * by the device driver.
40 */
41
42
43 #ifndef S_CONTEXT_H
44 #define S_CONTEXT_H
45
46 #include "main/mtypes.h"
47 #include "main/texcompress.h"
48 #include "program/prog_execute.h"
49 #include "swrast.h"
50 #include "s_fragprog.h"
51 #include "s_span.h"
52
53
54 typedef void (*texture_sample_func)(struct gl_context *ctx,
55 const struct gl_sampler_object *samp,
56 const struct gl_texture_object *tObj,
57 GLuint n, const GLfloat texcoords[][4],
58 const GLfloat lambda[], GLfloat rgba[][4]);
59
60 typedef void (*blend_func)(struct gl_context *ctx, GLuint n,
61 const GLubyte mask[],
62 GLvoid *src, const GLvoid *dst,
63 GLenum chanType);
64
65 typedef void (*swrast_point_func)( struct gl_context *ctx, const SWvertex *);
66
67 typedef void (*swrast_line_func)( struct gl_context *ctx,
68 const SWvertex *, const SWvertex *);
69
70 typedef void (*swrast_tri_func)( struct gl_context *ctx, const SWvertex *,
71 const SWvertex *, const SWvertex *);
72
73
74 typedef void (*validate_texture_image_func)(struct gl_context *ctx,
75 struct gl_texture_object *texObj,
76 GLuint face, GLuint level);
77
78
79 /**
80 * \defgroup Bitmasks
81 * Bitmasks to indicate which rasterization options are enabled
82 * (RasterMask)
83 */
84 /*@{*/
85 #define ALPHATEST_BIT 0x001 /**< Alpha-test pixels */
86 #define BLEND_BIT 0x002 /**< Blend pixels */
87 #define DEPTH_BIT 0x004 /**< Depth-test pixels */
88 #define FOG_BIT 0x008 /**< Fog pixels */
89 #define LOGIC_OP_BIT 0x010 /**< Apply logic op in software */
90 #define CLIP_BIT 0x020 /**< Scissor or window clip pixels */
91 #define STENCIL_BIT 0x040 /**< Stencil pixels */
92 #define MASKING_BIT 0x080 /**< Do glColorMask or glIndexMask */
93 #define MULTI_DRAW_BIT 0x400 /**< Write to more than one color- */
94 /**< buffer or no buffers. */
95 #define OCCLUSION_BIT 0x800 /**< GL_HP_occlusion_test enabled */
96 #define TEXTURE_BIT 0x1000 /**< Texturing really enabled */
97 #define FRAGPROG_BIT 0x2000 /**< Fragment program enabled */
98 #define ATIFRAGSHADER_BIT 0x4000 /**< ATI Fragment shader enabled */
99 #define CLAMPING_BIT 0x8000 /**< Clamp colors to [0,1] */
100 /*@}*/
101
102 #define _SWRAST_NEW_RASTERMASK (_NEW_BUFFERS| \
103 _NEW_SCISSOR| \
104 _NEW_COLOR| \
105 _NEW_DEPTH| \
106 _NEW_FOG| \
107 _NEW_PROGRAM| \
108 _NEW_STENCIL| \
109 _NEW_TEXTURE| \
110 _NEW_VIEWPORT| \
111 _NEW_DEPTH)
112
113
114 struct swrast_texture_image;
115
116
117 /**
118 * Fetch a texel from texture image at given position.
119 */
120 typedef void (*FetchTexelFunc)(const struct swrast_texture_image *texImage,
121 GLint col, GLint row, GLint img,
122 GLfloat *texelOut);
123
124
125 /**
126 * Subclass of gl_texture_image.
127 * We need extra fields/info to keep tracking of mapped texture buffers,
128 * strides and Fetch functions.
129 */
130 struct swrast_texture_image
131 {
132 struct gl_texture_image Base;
133
134 GLboolean _IsPowerOfTwo; /**< Are all dimensions powers of two? */
135
136 /** used for mipmap LOD computation */
137 GLfloat WidthScale, HeightScale, DepthScale;
138
139 /**
140 * Byte stride between rows in ImageSlices.
141 *
142 * For compressed textures, this is the byte stride between one row of
143 * blocks and the next row of blocks.
144 *
145 * Only valid while one of the ImageSlices is mapped, and must be the same
146 * between all slices.
147 */
148 GLint RowStride;
149 /**
150 * When a texture image is mapped for swrast, this array contains pointers
151 * to the beginning of each slice.
152 *
153 * For swrast-allocated textures, these pointers will always stay
154 * initialized to point within Buffer.
155 */
156 void **ImageSlices;
157
158 /** Malloc'd texture memory */
159 GLubyte *Buffer;
160
161 FetchTexelFunc FetchTexel;
162
163 /** For fetching texels from compressed textures */
164 compressed_fetch_func FetchCompressedTexel;
165 };
166
167
168 /** cast wrapper */
169 static inline struct swrast_texture_image *
swrast_texture_image(struct gl_texture_image * img)170 swrast_texture_image(struct gl_texture_image *img)
171 {
172 return (struct swrast_texture_image *) img;
173 }
174
175 /** cast wrapper */
176 static inline const struct swrast_texture_image *
swrast_texture_image_const(const struct gl_texture_image * img)177 swrast_texture_image_const(const struct gl_texture_image *img)
178 {
179 return (const struct swrast_texture_image *) img;
180 }
181
182
183 /**
184 * Subclass of gl_renderbuffer with extra fields needed for software
185 * rendering.
186 */
187 struct swrast_renderbuffer
188 {
189 struct gl_renderbuffer Base;
190
191 GLubyte *Buffer; /**< The malloc'd memory for buffer */
192
193 /** These fields are only valid while buffer is mapped for rendering */
194 GLubyte *Map;
195 GLint RowStride; /**< in bytes */
196
197 /** For span rendering */
198 GLenum ColorType;
199 };
200
201
202 /** cast wrapper */
203 static inline struct swrast_renderbuffer *
swrast_renderbuffer(struct gl_renderbuffer * img)204 swrast_renderbuffer(struct gl_renderbuffer *img)
205 {
206 return (struct swrast_renderbuffer *) img;
207 }
208
209
210
211 /**
212 * \struct SWcontext
213 * \brief Per-context state that's private to the software rasterizer module.
214 */
215 typedef struct
216 {
217 /** Driver interface:
218 */
219 struct swrast_device_driver Driver;
220
221 /** Configuration mechanisms to make software rasterizer match
222 * characteristics of the hardware rasterizer (if present):
223 */
224 GLboolean AllowVertexFog;
225 GLboolean AllowPixelFog;
226
227 /** Derived values, invalidated on statechanges, updated from
228 * _swrast_validate_derived():
229 */
230 GLbitfield _RasterMask;
231 GLfloat _BackfaceSign; /** +1 or -1 */
232 GLfloat _BackfaceCullSign; /** +1, 0, or -1 */
233 GLboolean _PreferPixelFog; /* Compute fog blend factor per fragment? */
234 GLboolean _TextureCombinePrimary;
235 GLboolean _FogEnabled;
236 GLboolean _DeferredTexture;
237
238 /** List/array of the fragment attributes to interpolate */
239 GLuint _ActiveAttribs[VARYING_SLOT_MAX];
240 /** Same info, but as a bitmask of VARYING_BIT_x bits */
241 GLbitfield64 _ActiveAttribMask;
242 /** Number of fragment attributes to interpolate */
243 GLuint _NumActiveAttribs;
244 /** Indicates how each attrib is to be interpolated (lines/tris) */
245 GLenum _InterpMode[VARYING_SLOT_MAX]; /* GL_FLAT or GL_SMOOTH (for now) */
246
247 /* Working values:
248 */
249 GLuint StippleCounter; /**< Line stipple counter */
250 GLuint PointLineFacing;
251 GLbitfield NewState;
252 GLuint StateChanges;
253 GLenum Primitive; /* current primitive being drawn (ala glBegin) */
254 GLboolean SpecularVertexAdd; /**< Add specular/secondary color per vertex */
255
256 void (*InvalidateState)( struct gl_context *ctx, GLbitfield new_state );
257
258 /**
259 * When the NewState mask intersects these masks, we invalidate the
260 * Point/Line/Triangle function pointers below.
261 */
262 /*@{*/
263 GLbitfield InvalidatePointMask;
264 GLbitfield InvalidateLineMask;
265 GLbitfield InvalidateTriangleMask;
266 /*@}*/
267
268 /**
269 * Device drivers plug in functions for these callbacks.
270 * Will be called when the GL state change mask intersects the above masks.
271 */
272 /*@{*/
273 void (*choose_point)( struct gl_context * );
274 void (*choose_line)( struct gl_context * );
275 void (*choose_triangle)( struct gl_context * );
276 /*@}*/
277
278 /**
279 * Current point, line and triangle drawing functions.
280 */
281 /*@{*/
282 swrast_point_func Point;
283 swrast_line_func Line;
284 swrast_tri_func Triangle;
285 /*@}*/
286
287 /**
288 * Placeholders for when separate specular (or secondary color) is
289 * enabled but texturing is not.
290 */
291 /*@{*/
292 swrast_point_func SpecPoint;
293 swrast_line_func SpecLine;
294 swrast_tri_func SpecTriangle;
295 /*@}*/
296
297 /**
298 * Typically, we'll allocate a sw_span structure as a local variable
299 * and set its 'array' pointer to point to this object. The reason is
300 * this object is big and causes problems when allocated on the stack
301 * on some systems.
302 */
303 SWspanarrays *SpanArrays;
304 SWspanarrays *ZoomedArrays; /**< For pixel zooming */
305
306 /**
307 * Used to buffer N GL_POINTS, instead of rendering one by one.
308 */
309 SWspan PointSpan;
310
311 /** Internal hooks, kept up to date by the same mechanism as above.
312 */
313 blend_func BlendFunc;
314 texture_sample_func TextureSample[MAX_COMBINED_TEXTURE_IMAGE_UNITS];
315
316 /** Buffer for saving the sampled texture colors.
317 * Needed for GL_ARB_texture_env_crossbar implementation.
318 */
319 GLfloat *TexelBuffer;
320
321 validate_texture_image_func ValidateTextureImage;
322
323 /** State used during execution of fragment programs */
324 struct gl_program_machine FragProgMachine;
325
326 /** Temporary arrays for stencil operations. To avoid large stack
327 * allocations.
328 */
329 struct {
330 GLubyte *buf1, *buf2, *buf3, *buf4;
331 } stencil_temp;
332
333 } SWcontext;
334
335
336 extern void
337 _swrast_validate_derived( struct gl_context *ctx );
338
339 extern void
340 _swrast_update_texture_samplers(struct gl_context *ctx);
341
342
343 /** Return SWcontext for the given struct gl_context */
344 static inline SWcontext *
SWRAST_CONTEXT(struct gl_context * ctx)345 SWRAST_CONTEXT(struct gl_context *ctx)
346 {
347 return (SWcontext *) ctx->swrast_context;
348 }
349
350 /** const version of above */
351 static inline const SWcontext *
CONST_SWRAST_CONTEXT(const struct gl_context * ctx)352 CONST_SWRAST_CONTEXT(const struct gl_context *ctx)
353 {
354 return (const SWcontext *) ctx->swrast_context;
355 }
356
357
358 /**
359 * Called prior to framebuffer reading/writing.
360 * For drivers that rely on swrast for fallback rendering, this is the
361 * driver's opportunity to map renderbuffers and textures.
362 */
363 static inline void
swrast_render_start(struct gl_context * ctx)364 swrast_render_start(struct gl_context *ctx)
365 {
366 SWcontext *swrast = SWRAST_CONTEXT(ctx);
367 if (swrast->Driver.SpanRenderStart)
368 swrast->Driver.SpanRenderStart(ctx);
369 }
370
371
372 /** Called after framebuffer reading/writing */
373 static inline void
swrast_render_finish(struct gl_context * ctx)374 swrast_render_finish(struct gl_context *ctx)
375 {
376 SWcontext *swrast = SWRAST_CONTEXT(ctx);
377 if (swrast->Driver.SpanRenderFinish)
378 swrast->Driver.SpanRenderFinish(ctx);
379 }
380
381
382 extern void
383 _swrast_span_render_start(struct gl_context *ctx);
384
385 extern void
386 _swrast_span_render_finish(struct gl_context *ctx);
387
388 extern void
389 _swrast_map_textures(struct gl_context *ctx);
390
391 extern void
392 _swrast_unmap_textures(struct gl_context *ctx);
393
394 extern unsigned int
395 _swrast_teximage_slice_height(struct gl_texture_image *texImage);
396
397 extern void
398 _swrast_map_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
399
400 extern void
401 _swrast_unmap_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
402
403
404 extern void
405 _swrast_map_renderbuffers(struct gl_context *ctx);
406
407 extern void
408 _swrast_unmap_renderbuffers(struct gl_context *ctx);
409
410
411 /**
412 * Size of an RGBA pixel, in bytes, for given datatype.
413 */
414 #define RGBA_PIXEL_SIZE(TYPE) \
415 ((TYPE == GL_UNSIGNED_BYTE) ? 4 * sizeof(GLubyte) : \
416 ((TYPE == GL_UNSIGNED_SHORT) ? 4 * sizeof(GLushort) \
417 : 4 * sizeof(GLfloat)))
418
419
420
421 /*
422 * Fixed point arithmetic macros
423 */
424 #ifndef FIXED_FRAC_BITS
425 #define FIXED_FRAC_BITS 11
426 #endif
427
428 #define FIXED_SHIFT FIXED_FRAC_BITS
429 #define FIXED_ONE (1 << FIXED_SHIFT)
430 #define FIXED_HALF (1 << (FIXED_SHIFT-1))
431 #define FIXED_FRAC_MASK (FIXED_ONE - 1)
432 #define FIXED_INT_MASK (~FIXED_FRAC_MASK)
433 #define FIXED_EPSILON 1
434 #define FIXED_SCALE ((float) FIXED_ONE)
435 #define FIXED_DBL_SCALE ((double) FIXED_ONE)
436 #define FloatToFixed(X) (IROUND((X) * FIXED_SCALE))
437 #define FixedToDouble(X) ((X) * (1.0 / FIXED_DBL_SCALE))
438 #define IntToFixed(I) ((I) << FIXED_SHIFT)
439 #define FixedToInt(X) ((X) >> FIXED_SHIFT)
440 #define FixedToUns(X) (((unsigned int)(X)) >> FIXED_SHIFT)
441 #define FixedCeil(X) (((X) + FIXED_ONE - FIXED_EPSILON) & FIXED_INT_MASK)
442 #define FixedFloor(X) ((X) & FIXED_INT_MASK)
443 #define FixedToFloat(X) ((X) * (1.0F / FIXED_SCALE))
444 #define PosFloatToFixed(X) FloatToFixed(X)
445 #define SignedFloatToFixed(X) FloatToFixed(X)
446
447
448
449 /*
450 * XXX these macros are just bandages for now in order to make
451 * CHAN_BITS==32 compile cleanly.
452 * These should probably go elsewhere at some point.
453 */
454 #if CHAN_TYPE == GL_FLOAT
455 #define ChanToFixed(X) (X)
456 #define FixedToChan(X) (X)
457 #else
458 #define ChanToFixed(X) IntToFixed(X)
459 #define FixedToChan(X) FixedToInt(X)
460 #endif
461
462
463 /**
464 * For looping over fragment attributes in the pointe, line
465 * triangle rasterizers.
466 */
467 #define ATTRIB_LOOP_BEGIN \
468 { \
469 GLuint a; \
470 for (a = 0; a < swrast->_NumActiveAttribs; a++) { \
471 const GLuint attr = swrast->_ActiveAttribs[a];
472
473 #define ATTRIB_LOOP_END } }
474
475
476 /**
477 * Return the address of a pixel value in a mapped renderbuffer.
478 */
479 static inline GLubyte *
_swrast_pixel_address(struct gl_renderbuffer * rb,GLint x,GLint y)480 _swrast_pixel_address(struct gl_renderbuffer *rb, GLint x, GLint y)
481 {
482 struct swrast_renderbuffer *srb = swrast_renderbuffer(rb);
483 const GLint bpp = _mesa_get_format_bytes(rb->Format);
484 const GLint rowStride = srb->RowStride;
485 assert(x >= 0);
486 assert(y >= 0);
487 /* NOTE: using <= only because of s_tritemp.h which gets a pixel
488 * address but doesn't necessarily access it.
489 */
490 assert(x <= (GLint) rb->Width);
491 assert(y <= (GLint) rb->Height);
492 assert(srb->Map);
493 return (GLubyte *) srb->Map + y * rowStride + x * bpp;
494 }
495
496
497
498 #endif
499