gallium/include: update some comments
[mesa.git] / src / gallium / include / pipe / p_state.h
1 /**************************************************************************
2 *
3 * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
4 * 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
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27
28
29 /**
30 * @file
31 *
32 * Abstract graphics pipe state objects.
33 *
34 * Basic notes:
35 * 1. Want compact representations, so we use bitfields.
36 * 2. Put bitfields before other (GLfloat) fields.
37 */
38
39
40 #ifndef PIPE_STATE_H
41 #define PIPE_STATE_H
42
43 #include "p_compiler.h"
44 #include "p_defines.h"
45 #include "p_format.h"
46 #include "p_refcnt.h"
47 #include "p_screen.h"
48
49
50 #ifdef __cplusplus
51 extern "C" {
52 #endif
53
54
55 /**
56 * Implementation limits
57 */
58 #define PIPE_MAX_ATTRIBS 32
59 #define PIPE_MAX_CLIP_PLANES 6
60 #define PIPE_MAX_COLOR_BUFS 8
61 #define PIPE_MAX_CONSTANT 32
62 #define PIPE_MAX_SAMPLERS 16
63 #define PIPE_MAX_SHADER_INPUTS 16
64 #define PIPE_MAX_SHADER_OUTPUTS 16
65 #define PIPE_MAX_TEXTURE_LEVELS 16
66
67
68 /* fwd decls */
69 struct pipe_surface;
70
71
72 /**
73 * The driver will certainly subclass this to include actual memory
74 * management information.
75 */
76 struct pipe_buffer
77 {
78 struct pipe_reference reference;
79 unsigned size;
80 struct pipe_screen *screen;
81 unsigned alignment;
82 unsigned usage;
83 };
84
85
86 /**
87 * Primitive (point/line/tri) rasterization info
88 */
89 struct pipe_rasterizer_state
90 {
91 unsigned flatshade:1;
92 unsigned light_twoside:1;
93 unsigned front_winding:2; /**< PIPE_WINDING_x */
94 unsigned cull_mode:2; /**< PIPE_WINDING_x */
95 unsigned fill_cw:2; /**< PIPE_POLYGON_MODE_x */
96 unsigned fill_ccw:2; /**< PIPE_POLYGON_MODE_x */
97 unsigned offset_cw:1;
98 unsigned offset_ccw:1;
99 unsigned scissor:1;
100 unsigned poly_smooth:1;
101 unsigned poly_stipple_enable:1;
102 unsigned point_smooth:1;
103 unsigned point_sprite:1;
104 unsigned point_size_per_vertex:1; /**< size computed in vertex shader */
105 unsigned multisample:1; /* XXX maybe more ms state in future */
106 unsigned line_smooth:1;
107 unsigned line_stipple_enable:1;
108 unsigned line_stipple_factor:8; /**< [1..256] actually */
109 unsigned line_stipple_pattern:16;
110 unsigned line_last_pixel:1;
111
112 /**
113 * Vertex coordinates are pre-transformed to screen space. Skip
114 * the vertex shader, clipping and viewport processing. Note that
115 * a vertex shader is still needed though, to indicate the mapping
116 * from vertex elements to fragment shader input semantics.
117 *
118 * XXX: considered for removal.
119 */
120 unsigned bypass_vs_clip_and_viewport:1;
121
122 /**
123 * Use the first vertex of a primitive as the provoking vertex for
124 * flat shading.
125 */
126 unsigned flatshade_first:1;
127
128 /**
129 * When true, triangle rasterization uses (0.5, 0.5) pixel centers
130 * for determining pixel ownership.
131 *
132 * When false, triangle rasterization uses (0,0) pixel centers for
133 * determining pixel ownership.
134 *
135 * Triangle rasterization always uses a 'top,left' rule for pixel
136 * ownership, this just alters which point we consider the pixel
137 * center for that test.
138 */
139 unsigned gl_rasterization_rules:1;
140
141 float line_width;
142 float point_size; /**< used when no per-vertex size */
143 float point_size_min; /* XXX - temporary, will go away */
144 float point_size_max; /* XXX - temporary, will go away */
145 float offset_units;
146 float offset_scale;
147 ubyte sprite_coord_mode[PIPE_MAX_SHADER_OUTPUTS]; /**< PIPE_SPRITE_COORD_ */
148 };
149
150
151 struct pipe_poly_stipple
152 {
153 unsigned stipple[32];
154 };
155
156
157 struct pipe_viewport_state
158 {
159 float scale[4];
160 float translate[4];
161 };
162
163
164 struct pipe_scissor_state
165 {
166 unsigned minx:16;
167 unsigned miny:16;
168 unsigned maxx:16;
169 unsigned maxy:16;
170 };
171
172
173 struct pipe_clip_state
174 {
175 float ucp[PIPE_MAX_CLIP_PLANES][4];
176 unsigned nr;
177 };
178
179
180 /**
181 * Constants for vertex/fragment shaders
182 */
183 struct pipe_constant_buffer
184 {
185 struct pipe_buffer *buffer;
186 };
187
188
189 struct pipe_shader_state
190 {
191 const struct tgsi_token *tokens;
192 };
193
194
195 struct pipe_depth_state
196 {
197 unsigned enabled:1; /**< depth test enabled? */
198 unsigned writemask:1; /**< allow depth buffer writes? */
199 unsigned func:3; /**< depth test func (PIPE_FUNC_x) */
200 unsigned occlusion_count:1; /**< do occlusion counting? */
201 };
202
203
204 struct pipe_stencil_state
205 {
206 unsigned enabled:1; /**< stencil[0]: stencil enabled, stencil[1]: two-side enabled */
207 unsigned func:3; /**< PIPE_FUNC_x */
208 unsigned fail_op:3; /**< PIPE_STENCIL_OP_x */
209 unsigned zpass_op:3; /**< PIPE_STENCIL_OP_x */
210 unsigned zfail_op:3; /**< PIPE_STENCIL_OP_x */
211 ubyte ref_value;
212 ubyte valuemask;
213 ubyte writemask;
214 };
215
216
217 struct pipe_alpha_state
218 {
219 unsigned enabled:1;
220 unsigned func:3; /**< PIPE_FUNC_x */
221 float ref_value; /**< reference value */
222 };
223
224
225 struct pipe_depth_stencil_alpha_state
226 {
227 struct pipe_depth_state depth;
228 struct pipe_stencil_state stencil[2]; /**< [0] = front, [1] = back */
229 struct pipe_alpha_state alpha;
230 };
231
232
233 struct pipe_blend_state
234 {
235 unsigned blend_enable:1;
236
237 unsigned rgb_func:3; /**< PIPE_BLEND_x */
238 unsigned rgb_src_factor:5; /**< PIPE_BLENDFACTOR_x */
239 unsigned rgb_dst_factor:5; /**< PIPE_BLENDFACTOR_x */
240
241 unsigned alpha_func:3; /**< PIPE_BLEND_x */
242 unsigned alpha_src_factor:5; /**< PIPE_BLENDFACTOR_x */
243 unsigned alpha_dst_factor:5; /**< PIPE_BLENDFACTOR_x */
244
245 unsigned logicop_enable:1;
246 unsigned logicop_func:4; /**< PIPE_LOGICOP_x */
247
248 unsigned colormask:4; /**< bitmask of PIPE_MASK_R/G/B/A */
249 unsigned dither:1;
250 };
251
252
253 struct pipe_blend_color
254 {
255 float color[4];
256 };
257
258
259 struct pipe_framebuffer_state
260 {
261 unsigned width, height;
262
263 /** multiple colorbuffers for multiple render targets */
264 unsigned nr_cbufs;
265 struct pipe_surface *cbufs[PIPE_MAX_COLOR_BUFS];
266
267 struct pipe_surface *zsbuf; /**< Z/stencil buffer */
268 };
269
270
271 /**
272 * Texture sampler state.
273 */
274 struct pipe_sampler_state
275 {
276 unsigned wrap_s:3; /**< PIPE_TEX_WRAP_x */
277 unsigned wrap_t:3; /**< PIPE_TEX_WRAP_x */
278 unsigned wrap_r:3; /**< PIPE_TEX_WRAP_x */
279 unsigned min_img_filter:2; /**< PIPE_TEX_FILTER_x */
280 unsigned min_mip_filter:2; /**< PIPE_TEX_MIPFILTER_x */
281 unsigned mag_img_filter:2; /**< PIPE_TEX_FILTER_x */
282 unsigned compare_mode:1; /**< PIPE_TEX_COMPARE_x */
283 unsigned compare_func:3; /**< PIPE_FUNC_x */
284 unsigned normalized_coords:1; /**< Are coords normalized to [0,1]? */
285 unsigned prefilter:4; /**< Wierd sampling state exposed by some api's */
286 float lod_bias; /**< LOD/lambda bias */
287 float min_lod, max_lod; /**< LOD clamp range, after bias */
288 float border_color[4];
289 float max_anisotropy;
290 };
291
292
293 /**
294 * 2D surface. This is basically a view into a memory buffer.
295 * May be a renderbuffer, texture mipmap level, etc.
296 */
297 struct pipe_surface
298 {
299 struct pipe_reference reference;
300 enum pipe_format format; /**< PIPE_FORMAT_x */
301 unsigned width; /**< logical width in pixels */
302 unsigned height; /**< logical height in pixels */
303 unsigned layout; /**< PIPE_SURFACE_LAYOUT_x */
304 unsigned offset; /**< offset from start of buffer, in bytes */
305 unsigned usage; /**< PIPE_BUFFER_USAGE_* */
306
307 unsigned zslice;
308 struct pipe_texture *texture; /**< texture into which this is a view */
309 unsigned face;
310 unsigned level;
311 };
312
313
314 /**
315 * Transfer object. For data transfer to/from a texture.
316 */
317 struct pipe_transfer
318 {
319 enum pipe_format format; /**< PIPE_FORMAT_x */
320 unsigned x; /**< x offset from start of texture image */
321 unsigned y; /**< y offset from start of texture image */
322 unsigned width; /**< logical width in pixels */
323 unsigned height; /**< logical height in pixels */
324 struct pipe_format_block block;
325 unsigned nblocksx; /**< allocated width in blocks */
326 unsigned nblocksy; /**< allocated height in blocks */
327 unsigned stride; /**< stride in bytes between rows of blocks */
328 enum pipe_transfer_usage usage; /**< PIPE_TRANSFER_* */
329
330 struct pipe_texture *texture; /**< texture to transfer to/from */
331 unsigned face;
332 unsigned level;
333 unsigned zslice;
334 };
335
336
337 /**
338 * Texture object.
339 */
340 struct pipe_texture
341 {
342 struct pipe_reference reference;
343
344 enum pipe_texture_target target; /**< PIPE_TEXTURE_x */
345 enum pipe_format format; /**< PIPE_FORMAT_x */
346
347 unsigned width[PIPE_MAX_TEXTURE_LEVELS];
348 unsigned height[PIPE_MAX_TEXTURE_LEVELS];
349 unsigned depth[PIPE_MAX_TEXTURE_LEVELS];
350
351 struct pipe_format_block block;
352 unsigned nblocksx[PIPE_MAX_TEXTURE_LEVELS]; /**< allocated width in blocks */
353 unsigned nblocksy[PIPE_MAX_TEXTURE_LEVELS]; /**< allocated height in blocks */
354
355 unsigned last_level:8; /**< Index of last mipmap level present/defined */
356
357 unsigned nr_samples:8; /**< for multisampled surfaces, nr of samples */
358
359 unsigned tex_usage; /* PIPE_TEXTURE_USAGE_* */
360
361 struct pipe_screen *screen; /**< screen that this texture belongs to */
362 };
363
364
365 /**
366 * A vertex buffer. Typically, all the vertex data/attributes for
367 * drawing something will be in one buffer. But it's also possible, for
368 * example, to put colors in one buffer and texcoords in another.
369 */
370 struct pipe_vertex_buffer
371 {
372 unsigned stride; /**< stride to same attrib in next vertex, in bytes */
373 unsigned max_index; /**< number of vertices in this buffer */
374 unsigned buffer_offset; /**< offset to start of data in buffer, in bytes */
375 struct pipe_buffer *buffer; /**< the actual buffer */
376 };
377
378
379 /**
380 * Information to describe a vertex attribute (position, color, etc)
381 */
382 struct pipe_vertex_element
383 {
384 /** Offset of this attribute, in bytes, from the start of the vertex */
385 unsigned src_offset;
386
387 /** Which vertex_buffer (as given to pipe->set_vertex_buffer()) does
388 * this attribute live in?
389 */
390 unsigned vertex_buffer_index:8;
391 unsigned nr_components:8;
392
393 enum pipe_format src_format; /**< PIPE_FORMAT_* */
394 };
395
396
397 /* Reference counting helper functions */
398 static INLINE void
399 pipe_buffer_reference(struct pipe_buffer **ptr, struct pipe_buffer *buf)
400 {
401 struct pipe_buffer *old_buf = *ptr;
402
403 if (pipe_reference((struct pipe_reference **)ptr, &buf->reference))
404 old_buf->screen->buffer_destroy(old_buf);
405 }
406
407 static INLINE void
408 pipe_surface_reference(struct pipe_surface **ptr, struct pipe_surface *surf)
409 {
410 struct pipe_surface *old_surf = *ptr;
411
412 if (pipe_reference((struct pipe_reference **)ptr, &surf->reference))
413 old_surf->texture->screen->tex_surface_destroy(old_surf);
414 }
415
416 static INLINE void
417 pipe_texture_reference(struct pipe_texture **ptr, struct pipe_texture *tex)
418 {
419 struct pipe_texture *old_tex = *ptr;
420
421 if (pipe_reference((struct pipe_reference **)ptr, &tex->reference))
422 old_tex->screen->texture_destroy(old_tex);
423 }
424
425
426 #ifdef __cplusplus
427 }
428 #endif
429
430 #endif