s_context.h revision c1f859d4 
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/mtypes.h"
47#include "shader/prog_execute.h"
48#include "swrast.h"
49#include "s_span.h"
50
51
52typedef void (*texture_sample_func)(GLcontext *ctx,
53                                    const struct gl_texture_object *tObj,
54                                    GLuint n, const GLfloat texcoords[][4],
55                                    const GLfloat lambda[], GLchan rgba[][4]);
56
57typedef void (_ASMAPIP blend_func)( GLcontext *ctx, GLuint n,
58                                    const GLubyte mask[],
59                                    GLvoid *src, const GLvoid *dst,
60                                    GLenum chanType);
61
62typedef void (*swrast_point_func)( GLcontext *ctx, const SWvertex *);
63
64typedef void (*swrast_line_func)( GLcontext *ctx,
65                                  const SWvertex *, const SWvertex *);
66
67typedef void (*swrast_tri_func)( GLcontext *ctx, const SWvertex *,
68                                 const SWvertex *, const SWvertex *);
69
70
71typedef void (*validate_texture_image_func)(GLcontext *ctx,
72                                            struct gl_texture_object *texObj,
73                                            GLuint face, GLuint level);
74
75
76/**
77 * \defgroup Bitmasks
78 * Bitmasks to indicate which rasterization options are enabled
79 * (RasterMask)
80 */
81/*@{*/
82#define ALPHATEST_BIT		0x001	/**< Alpha-test pixels */
83#define BLEND_BIT		0x002	/**< Blend pixels */
84#define DEPTH_BIT		0x004	/**< Depth-test pixels */
85#define FOG_BIT			0x008	/**< Fog pixels */
86#define LOGIC_OP_BIT		0x010	/**< Apply logic op in software */
87#define CLIP_BIT		0x020	/**< Scissor or window clip pixels */
88#define STENCIL_BIT		0x040	/**< Stencil pixels */
89#define MASKING_BIT		0x080	/**< Do glColorMask or glIndexMask */
90#define MULTI_DRAW_BIT		0x400	/**< Write to more than one color- */
91                                        /**< buffer or no buffers. */
92#define OCCLUSION_BIT           0x800   /**< GL_HP_occlusion_test enabled */
93#define TEXTURE_BIT		0x1000	/**< Texturing really enabled */
94#define FRAGPROG_BIT            0x2000  /**< Fragment program enabled */
95#define ATIFRAGSHADER_BIT       0x4000  /**< ATI Fragment shader enabled */
96#define CLAMPING_BIT            0x8000  /**< Clamp colors to [0,1] */
97/*@}*/
98
99#define _SWRAST_NEW_RASTERMASK (_NEW_BUFFERS|	\
100			        _NEW_SCISSOR|	\
101			        _NEW_COLOR|	\
102			        _NEW_DEPTH|	\
103			        _NEW_FOG|	\
104                                _NEW_PROGRAM|   \
105			        _NEW_STENCIL|	\
106			        _NEW_TEXTURE|	\
107			        _NEW_VIEWPORT|	\
108			        _NEW_DEPTH)
109
110
111/**
112 * \struct SWcontext
113 * \brief  Per-context state that's private to the software rasterizer module.
114 */
115typedef struct
116{
117   /** Driver interface:
118    */
119   struct swrast_device_driver Driver;
120
121   /** Configuration mechanisms to make software rasterizer match
122    * characteristics of the hardware rasterizer (if present):
123    */
124   GLboolean AllowVertexFog;
125   GLboolean AllowPixelFog;
126
127   /** Derived values, invalidated on statechanges, updated from
128    * _swrast_validate_derived():
129    */
130   GLbitfield _RasterMask;
131   GLfloat _BackfaceSign;      /** +1 or -1 */
132   GLfloat _BackfaceCullSign;  /** +1, 0, or -1 */
133   GLboolean _PreferPixelFog;    /* Compute fog blend factor per fragment? */
134   GLboolean _AnyTextureCombine;
135   GLboolean _FogEnabled;
136   GLboolean _DeferredTexture;
137   GLenum _FogMode;  /* either GL_FOG_MODE or fragment program's fog mode */
138
139   /** List/array of the fragment attributes to interpolate */
140   GLuint _ActiveAttribs[FRAG_ATTRIB_MAX];
141   /** Same info, but as a bitmask */
142   GLbitfield _ActiveAttribMask;
143   /** Number of fragment attributes to interpolate */
144   GLuint _NumActiveAttribs;
145   /** Indicates how each attrib is to be interpolated (lines/tris) */
146   GLenum _InterpMode[FRAG_ATTRIB_MAX]; /* GL_FLAT or GL_SMOOTH (for now) */
147
148   /* Accum buffer temporaries.
149    */
150   GLboolean _IntegerAccumMode;	/**< Storing unscaled integers? */
151   GLfloat _IntegerAccumScaler;	/**< Implicit scale factor */
152
153   /* Working values:
154    */
155   GLuint StippleCounter;    /**< Line stipple counter */
156   GLuint PointLineFacing;
157   GLbitfield NewState;
158   GLuint StateChanges;
159   GLenum Primitive;    /* current primitive being drawn (ala glBegin) */
160
161   void (*InvalidateState)( GLcontext *ctx, GLbitfield new_state );
162
163   /**
164    * When the NewState mask intersects these masks, we invalidate the
165    * Point/Line/Triangle function pointers below.
166    */
167   /*@{*/
168   GLbitfield InvalidatePointMask;
169   GLbitfield InvalidateLineMask;
170   GLbitfield InvalidateTriangleMask;
171   /*@}*/
172
173   /**
174    * Device drivers plug in functions for these callbacks.
175    * Will be called when the GL state change mask intersects the above masks.
176    */
177   /*@{*/
178   void (*choose_point)( GLcontext * );
179   void (*choose_line)( GLcontext * );
180   void (*choose_triangle)( GLcontext * );
181   /*@}*/
182
183   /**
184    * Current point, line and triangle drawing functions.
185    */
186   /*@{*/
187   swrast_point_func Point;
188   swrast_line_func Line;
189   swrast_tri_func Triangle;
190   /*@}*/
191
192   /**
193    * Placeholders for when separate specular (or secondary color) is
194    * enabled but texturing is not.
195    */
196   /*@{*/
197   swrast_point_func SpecPoint;
198   swrast_line_func SpecLine;
199   swrast_tri_func SpecTriangle;
200   /*@}*/
201
202   /**
203    * Typically, we'll allocate a sw_span structure as a local variable
204    * and set its 'array' pointer to point to this object.  The reason is
205    * this object is big and causes problems when allocated on the stack
206    * on some systems.
207    */
208   SWspanarrays *SpanArrays;
209   SWspanarrays *ZoomedArrays;  /**< For pixel zooming */
210
211   /**
212    * Used to buffer N GL_POINTS, instead of rendering one by one.
213    */
214   SWspan PointSpan;
215
216   /** Internal hooks, kept up to date by the same mechanism as above.
217    */
218   blend_func BlendFunc;
219   texture_sample_func TextureSample[MAX_TEXTURE_IMAGE_UNITS];
220
221   /** Buffer for saving the sampled texture colors.
222    * Needed for GL_ARB_texture_env_crossbar implementation.
223    */
224   GLchan *TexelBuffer;
225
226   validate_texture_image_func ValidateTextureImage;
227
228   /** State used during execution of fragment programs */
229   struct gl_program_machine FragProgMachine;
230
231} SWcontext;
232
233
234extern void
235_swrast_validate_derived( GLcontext *ctx );
236
237extern void
238_swrast_update_texture_samplers(GLcontext *ctx);
239
240
241#define SWRAST_CONTEXT(ctx) ((SWcontext *)ctx->swrast_context)
242
243#define RENDER_START(SWctx, GLctx)			\
244   do {							\
245      if ((SWctx)->Driver.SpanRenderStart) {		\
246         (*(SWctx)->Driver.SpanRenderStart)(GLctx);	\
247      }							\
248   } while (0)
249
250#define RENDER_FINISH(SWctx, GLctx)			\
251   do {							\
252      if ((SWctx)->Driver.SpanRenderFinish) {		\
253         (*(SWctx)->Driver.SpanRenderFinish)(GLctx);	\
254      }							\
255   } while (0)
256
257
258
259/**
260 * Size of an RGBA pixel, in bytes, for given datatype.
261 */
262#define RGBA_PIXEL_SIZE(TYPE)                                     \
263         ((TYPE == GL_UNSIGNED_BYTE) ? 4 * sizeof(GLubyte) :      \
264          ((TYPE == GL_UNSIGNED_SHORT) ? 4 * sizeof(GLushort)     \
265           : 4 * sizeof(GLfloat)))
266
267
268
269/*
270 * XXX these macros are just bandages for now in order to make
271 * CHAN_BITS==32 compile cleanly.
272 * These should probably go elsewhere at some point.
273 */
274#if CHAN_TYPE == GL_FLOAT
275#define ChanToFixed(X)  (X)
276#define FixedToChan(X)  (X)
277#else
278#define ChanToFixed(X)  IntToFixed(X)
279#define FixedToChan(X)  FixedToInt(X)
280#endif
281
282
283/**
284 * For looping over fragment attributes in the pointe, line
285 * triangle rasterizers.
286 */
287#define ATTRIB_LOOP_BEGIN                                \
288   {                                                     \
289      GLuint a;                                          \
290      for (a = 0; a < swrast->_NumActiveAttribs; a++) {  \
291         const GLuint attr = swrast->_ActiveAttribs[a];
292
293#define ATTRIB_LOOP_END } }
294
295
296
297#endif
298