1 /*
2 * Mesa 3-D graphics library
3 * Version: 6.5.3
4 *
5 * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR 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 <keith@tungstengraphics.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/compiler.h"
47 #include "main/mtypes.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 (_ASMAPIP 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 /** These fields only valid when texture memory is mapped */
140 GLint RowStride; /**< Padded width in units of texels */
141 GLuint *ImageOffsets; /**< if 3D texture: array [Depth] of offsets to
142 each 2D slice in 'Data', in texels */
143 GLubyte *Map; /**< Pointer to mapped image memory */
144
145 /** Malloc'd texture memory */
146 GLubyte *Buffer;
147
148 FetchTexelFunc FetchTexel;
149 };
150
151
152 /** cast wrapper */
153 static inline struct swrast_texture_image *
swrast_texture_image(struct gl_texture_image * img)154 swrast_texture_image(struct gl_texture_image *img)
155 {
156 return (struct swrast_texture_image *) img;
157 }
158
159 /** cast wrapper */
160 static inline const struct swrast_texture_image *
swrast_texture_image_const(const struct gl_texture_image * img)161 swrast_texture_image_const(const struct gl_texture_image *img)
162 {
163 return (const struct swrast_texture_image *) img;
164 }
165
166
167 /**
168 * Subclass of gl_renderbuffer with extra fields needed for software
169 * rendering.
170 */
171 struct swrast_renderbuffer
172 {
173 struct gl_renderbuffer Base;
174
175 GLubyte *Buffer; /**< The malloc'd memory for buffer */
176
177 /** These fields are only valid while buffer is mapped for rendering */
178 GLubyte *Map;
179 GLint RowStride; /**< in bytes */
180
181 /** For span rendering */
182 GLenum ColorType;
183 };
184
185
186 /** cast wrapper */
187 static inline struct swrast_renderbuffer *
swrast_renderbuffer(struct gl_renderbuffer * img)188 swrast_renderbuffer(struct gl_renderbuffer *img)
189 {
190 return (struct swrast_renderbuffer *) img;
191 }
192
193
194
195 /**
196 * \struct SWcontext
197 * \brief Per-context state that's private to the software rasterizer module.
198 */
199 typedef struct
200 {
201 /** Driver interface:
202 */
203 struct swrast_device_driver Driver;
204
205 /** Configuration mechanisms to make software rasterizer match
206 * characteristics of the hardware rasterizer (if present):
207 */
208 GLboolean AllowVertexFog;
209 GLboolean AllowPixelFog;
210
211 /** Derived values, invalidated on statechanges, updated from
212 * _swrast_validate_derived():
213 */
214 GLbitfield _RasterMask;
215 GLfloat _BackfaceSign; /** +1 or -1 */
216 GLfloat _BackfaceCullSign; /** +1, 0, or -1 */
217 GLboolean _PreferPixelFog; /* Compute fog blend factor per fragment? */
218 GLboolean _TextureCombinePrimary;
219 GLboolean _FogEnabled;
220 GLboolean _DeferredTexture;
221
222 /** List/array of the fragment attributes to interpolate */
223 GLuint _ActiveAttribs[FRAG_ATTRIB_MAX];
224 /** Same info, but as a bitmask of FRAG_BIT_x bits */
225 GLbitfield64 _ActiveAttribMask;
226 /** Number of fragment attributes to interpolate */
227 GLuint _NumActiveAttribs;
228 /** Indicates how each attrib is to be interpolated (lines/tris) */
229 GLenum _InterpMode[FRAG_ATTRIB_MAX]; /* GL_FLAT or GL_SMOOTH (for now) */
230
231 /* Working values:
232 */
233 GLuint StippleCounter; /**< Line stipple counter */
234 GLuint PointLineFacing;
235 GLbitfield NewState;
236 GLuint StateChanges;
237 GLenum Primitive; /* current primitive being drawn (ala glBegin) */
238 GLboolean SpecularVertexAdd; /**< Add specular/secondary color per vertex */
239
240 void (*InvalidateState)( struct gl_context *ctx, GLbitfield new_state );
241
242 /**
243 * When the NewState mask intersects these masks, we invalidate the
244 * Point/Line/Triangle function pointers below.
245 */
246 /*@{*/
247 GLbitfield InvalidatePointMask;
248 GLbitfield InvalidateLineMask;
249 GLbitfield InvalidateTriangleMask;
250 /*@}*/
251
252 /**
253 * Device drivers plug in functions for these callbacks.
254 * Will be called when the GL state change mask intersects the above masks.
255 */
256 /*@{*/
257 void (*choose_point)( struct gl_context * );
258 void (*choose_line)( struct gl_context * );
259 void (*choose_triangle)( struct gl_context * );
260 /*@}*/
261
262 /**
263 * Current point, line and triangle drawing functions.
264 */
265 /*@{*/
266 swrast_point_func Point;
267 swrast_line_func Line;
268 swrast_tri_func Triangle;
269 /*@}*/
270
271 /**
272 * Placeholders for when separate specular (or secondary color) is
273 * enabled but texturing is not.
274 */
275 /*@{*/
276 swrast_point_func SpecPoint;
277 swrast_line_func SpecLine;
278 swrast_tri_func SpecTriangle;
279 /*@}*/
280
281 /**
282 * Typically, we'll allocate a sw_span structure as a local variable
283 * and set its 'array' pointer to point to this object. The reason is
284 * this object is big and causes problems when allocated on the stack
285 * on some systems.
286 */
287 SWspanarrays *SpanArrays;
288 SWspanarrays *ZoomedArrays; /**< For pixel zooming */
289
290 /**
291 * Used to buffer N GL_POINTS, instead of rendering one by one.
292 */
293 SWspan PointSpan;
294
295 /** Internal hooks, kept up to date by the same mechanism as above.
296 */
297 blend_func BlendFunc;
298 texture_sample_func TextureSample[MAX_TEXTURE_IMAGE_UNITS];
299
300 /** Buffer for saving the sampled texture colors.
301 * Needed for GL_ARB_texture_env_crossbar implementation.
302 */
303 GLfloat *TexelBuffer;
304
305 validate_texture_image_func ValidateTextureImage;
306
307 /** State used during execution of fragment programs */
308 struct gl_program_machine FragProgMachine;
309
310 /** Temporary arrays for stencil operations. To avoid large stack
311 * allocations.
312 */
313 struct {
314 GLubyte *buf1, *buf2, *buf3, *buf4;
315 } stencil_temp;
316
317 } SWcontext;
318
319
320 extern void
321 _swrast_validate_derived( struct gl_context *ctx );
322
323 extern void
324 _swrast_update_texture_samplers(struct gl_context *ctx);
325
326
327 /** Return SWcontext for the given struct gl_context */
328 static inline SWcontext *
SWRAST_CONTEXT(struct gl_context * ctx)329 SWRAST_CONTEXT(struct gl_context *ctx)
330 {
331 return (SWcontext *) ctx->swrast_context;
332 }
333
334 /** const version of above */
335 static inline const SWcontext *
CONST_SWRAST_CONTEXT(const struct gl_context * ctx)336 CONST_SWRAST_CONTEXT(const struct gl_context *ctx)
337 {
338 return (const SWcontext *) ctx->swrast_context;
339 }
340
341
342 /**
343 * Called prior to framebuffer reading/writing.
344 * For drivers that rely on swrast for fallback rendering, this is the
345 * driver's opportunity to map renderbuffers and textures.
346 */
347 static inline void
swrast_render_start(struct gl_context * ctx)348 swrast_render_start(struct gl_context *ctx)
349 {
350 SWcontext *swrast = SWRAST_CONTEXT(ctx);
351 if (swrast->Driver.SpanRenderStart)
352 swrast->Driver.SpanRenderStart(ctx);
353 }
354
355
356 /** Called after framebuffer reading/writing */
357 static inline void
swrast_render_finish(struct gl_context * ctx)358 swrast_render_finish(struct gl_context *ctx)
359 {
360 SWcontext *swrast = SWRAST_CONTEXT(ctx);
361 if (swrast->Driver.SpanRenderFinish)
362 swrast->Driver.SpanRenderFinish(ctx);
363 }
364
365
366 extern void
367 _swrast_span_render_start(struct gl_context *ctx);
368
369 extern void
370 _swrast_span_render_finish(struct gl_context *ctx);
371
372 extern void
373 _swrast_map_textures(struct gl_context *ctx);
374
375 extern void
376 _swrast_unmap_textures(struct gl_context *ctx);
377
378 extern void
379 _swrast_map_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
380
381 extern void
382 _swrast_unmap_texture(struct gl_context *ctx, struct gl_texture_object *texObj);
383
384
385 extern void
386 _swrast_map_renderbuffers(struct gl_context *ctx);
387
388 extern void
389 _swrast_unmap_renderbuffers(struct gl_context *ctx);
390
391
392 /**
393 * Size of an RGBA pixel, in bytes, for given datatype.
394 */
395 #define RGBA_PIXEL_SIZE(TYPE) \
396 ((TYPE == GL_UNSIGNED_BYTE) ? 4 * sizeof(GLubyte) : \
397 ((TYPE == GL_UNSIGNED_SHORT) ? 4 * sizeof(GLushort) \
398 : 4 * sizeof(GLfloat)))
399
400
401
402 /*
403 * Fixed point arithmetic macros
404 */
405 #ifndef FIXED_FRAC_BITS
406 #define FIXED_FRAC_BITS 11
407 #endif
408
409 #define FIXED_SHIFT FIXED_FRAC_BITS
410 #define FIXED_ONE (1 << FIXED_SHIFT)
411 #define FIXED_HALF (1 << (FIXED_SHIFT-1))
412 #define FIXED_FRAC_MASK (FIXED_ONE - 1)
413 #define FIXED_INT_MASK (~FIXED_FRAC_MASK)
414 #define FIXED_EPSILON 1
415 #define FIXED_SCALE ((float) FIXED_ONE)
416 #define FIXED_DBL_SCALE ((double) FIXED_ONE)
417 #define FloatToFixed(X) (IROUND((X) * FIXED_SCALE))
418 #define FixedToDouble(X) ((X) * (1.0 / FIXED_DBL_SCALE))
419 #define IntToFixed(I) ((I) << FIXED_SHIFT)
420 #define FixedToInt(X) ((X) >> FIXED_SHIFT)
421 #define FixedToUns(X) (((unsigned int)(X)) >> FIXED_SHIFT)
422 #define FixedCeil(X) (((X) + FIXED_ONE - FIXED_EPSILON) & FIXED_INT_MASK)
423 #define FixedFloor(X) ((X) & FIXED_INT_MASK)
424 #define FixedToFloat(X) ((X) * (1.0F / FIXED_SCALE))
425 #define PosFloatToFixed(X) FloatToFixed(X)
426 #define SignedFloatToFixed(X) FloatToFixed(X)
427
428
429
430 /*
431 * XXX these macros are just bandages for now in order to make
432 * CHAN_BITS==32 compile cleanly.
433 * These should probably go elsewhere at some point.
434 */
435 #if CHAN_TYPE == GL_FLOAT
436 #define ChanToFixed(X) (X)
437 #define FixedToChan(X) (X)
438 #else
439 #define ChanToFixed(X) IntToFixed(X)
440 #define FixedToChan(X) FixedToInt(X)
441 #endif
442
443
444 /**
445 * For looping over fragment attributes in the pointe, line
446 * triangle rasterizers.
447 */
448 #define ATTRIB_LOOP_BEGIN \
449 { \
450 GLuint a; \
451 for (a = 0; a < swrast->_NumActiveAttribs; a++) { \
452 const GLuint attr = swrast->_ActiveAttribs[a];
453
454 #define ATTRIB_LOOP_END } }
455
456
457 /**
458 * Return the address of a pixel value in a mapped renderbuffer.
459 */
460 static inline GLubyte *
_swrast_pixel_address(struct gl_renderbuffer * rb,GLint x,GLint y)461 _swrast_pixel_address(struct gl_renderbuffer *rb, GLint x, GLint y)
462 {
463 struct swrast_renderbuffer *srb = swrast_renderbuffer(rb);
464 const GLint bpp = _mesa_get_format_bytes(rb->Format);
465 const GLint rowStride = srb->RowStride;
466 assert(x >= 0);
467 assert(y >= 0);
468 /* NOTE: using <= only because of s_tritemp.h which gets a pixel
469 * address but doesn't necessarily access it.
470 */
471 assert(x <= (GLint) rb->Width);
472 assert(y <= (GLint) rb->Height);
473 assert(srb->Map);
474 return (GLubyte *) srb->Map + y * rowStride + x * bpp;
475 }
476
477
478
479 #endif
480