1 /*
2  * Mesa 3-D graphics library
3  * Version:  6.5
4  *
5  * Copyright (C) 1999-2006  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/swrast.h
28  * \brief Public interface to the software rasterization functions.
29  * \author Keith Whitwell <keith@tungstengraphics.com>
30  */
31 
32 #ifndef SWRAST_H
33 #define SWRAST_H
34 
35 #include "main/mtypes.h"
36 #include "swrast/s_chan.h"
37 
38 
39 /**
40  * If non-zero use GLdouble for walking triangle edges, for better accuracy.
41  */
42 #define TRIANGLE_WALK_DOUBLE 0
43 
44 
45 /**
46  * Bits per depth buffer value (max is 32).
47  */
48 #ifndef DEFAULT_SOFTWARE_DEPTH_BITS
49 #define DEFAULT_SOFTWARE_DEPTH_BITS 16
50 #endif
51 /** Depth buffer data type */
52 #if DEFAULT_SOFTWARE_DEPTH_BITS <= 16
53 #define DEFAULT_SOFTWARE_DEPTH_TYPE GLushort
54 #else
55 #define DEFAULT_SOFTWARE_DEPTH_TYPE GLuint
56 #endif
57 
58 
59 /**
60  * Max image/surface/texture size.
61  */
62 #define SWRAST_MAX_WIDTH 16384
63 #define SWRAST_MAX_HEIGHT 16384
64 
65 
66 /**
67  * \struct SWvertex
68  * \brief Data-structure to handle vertices in the software rasterizer.
69  *
70  * The software rasterizer now uses this format for vertices.  Thus a
71  * 'RasterSetup' stage or other translation is required between the
72  * tnl module and the swrast rasterization functions.  This serves to
73  * isolate the swrast module from the internals of the tnl module, and
74  * improve its usefulness as a fallback mechanism for hardware
75  * drivers.
76  *
77  * wpos = attr[FRAG_ATTRIB_WPOS] and MUST BE THE FIRST values in the
78  * vertex because of the tnl clipping code.
79 
80  * wpos[0] and [1] are the screen-coords of SWvertex.
81  * wpos[2] is the z-buffer coord (if 16-bit Z buffer, in range [0,65535]).
82  * wpos[3] is 1/w where w is the clip-space W coord.  This is the value
83  * that clip{XYZ} were multiplied by to get ndc{XYZ}.
84  *
85  * Full software drivers:
86  *   - Register the rastersetup and triangle functions from
87  *     utils/software_helper.
88  *   - On statechange, update the rasterization pointers in that module.
89  *
90  * Rasterization hardware drivers:
91  *   - Keep native rastersetup.
92  *   - Implement native twoside,offset and unfilled triangle setup.
93  *   - Implement a translator from native vertices to swrast vertices.
94  *   - On partial fallback (mix of accelerated and unaccelerated
95  *   prims), call a pass-through function which translates native
96  *   vertices to SWvertices and calls the appropriate swrast function.
97  *   - On total fallback (vertex format insufficient for state or all
98  *     primitives unaccelerated), hook in swrast_setup instead.
99  */
100 typedef struct {
101    GLfloat attrib[FRAG_ATTRIB_MAX][4];
102    GLchan color[4];   /** integer color */
103    GLfloat pointSize;
104 } SWvertex;
105 
106 
107 #define FRAG_ATTRIB_CI FRAG_ATTRIB_COL0
108 
109 
110 struct swrast_device_driver;
111 
112 
113 /* These are the public-access functions exported from swrast.
114  */
115 
116 extern GLboolean
117 _swrast_CreateContext( struct gl_context *ctx );
118 
119 extern void
120 _swrast_DestroyContext( struct gl_context *ctx );
121 
122 /* Get a (non-const) reference to the device driver struct for swrast.
123  */
124 extern struct swrast_device_driver *
125 _swrast_GetDeviceDriverReference( struct gl_context *ctx );
126 
127 extern void
128 _swrast_Bitmap( struct gl_context *ctx,
129 		GLint px, GLint py,
130 		GLsizei width, GLsizei height,
131 		const struct gl_pixelstore_attrib *unpack,
132 		const GLubyte *bitmap );
133 
134 extern void
135 _swrast_CopyPixels( struct gl_context *ctx,
136 		    GLint srcx, GLint srcy,
137 		    GLint destx, GLint desty,
138 		    GLsizei width, GLsizei height,
139 		    GLenum type );
140 
141 extern GLboolean
142 swrast_fast_copy_pixels(struct gl_context *ctx,
143 			GLint srcX, GLint srcY, GLsizei width, GLsizei height,
144 			GLint dstX, GLint dstY, GLenum type);
145 
146 extern void
147 _swrast_DrawPixels( struct gl_context *ctx,
148 		    GLint x, GLint y,
149 		    GLsizei width, GLsizei height,
150 		    GLenum format, GLenum type,
151 		    const struct gl_pixelstore_attrib *unpack,
152 		    const GLvoid *pixels );
153 
154 extern void
155 _swrast_BlitFramebuffer(struct gl_context *ctx,
156                         GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
157                         GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
158                         GLbitfield mask, GLenum filter);
159 
160 extern void
161 _swrast_Clear(struct gl_context *ctx, GLbitfield buffers);
162 
163 
164 
165 /* Reset the stipple counter
166  */
167 extern void
168 _swrast_ResetLineStipple( struct gl_context *ctx );
169 
170 /**
171  * Indicates front/back facing for subsequent points/lines when drawing
172  * unfilled polygons.  Needed for two-side stencil.
173  */
174 extern void
175 _swrast_SetFacing(struct gl_context *ctx, GLuint facing);
176 
177 /* These will always render the correct point/line/triangle for the
178  * current state.
179  *
180  * For flatshaded primitives, the provoking vertex is the final one.
181  */
182 extern void
183 _swrast_Point( struct gl_context *ctx, const SWvertex *v );
184 
185 extern void
186 _swrast_Line( struct gl_context *ctx, const SWvertex *v0, const SWvertex *v1 );
187 
188 extern void
189 _swrast_Triangle( struct gl_context *ctx, const SWvertex *v0,
190                   const SWvertex *v1, const SWvertex *v2 );
191 
192 extern void
193 _swrast_Quad( struct gl_context *ctx,
194               const SWvertex *v0, const SWvertex *v1,
195 	      const SWvertex *v2,  const SWvertex *v3);
196 
197 extern void
198 _swrast_flush( struct gl_context *ctx );
199 
200 extern void
201 _swrast_render_primitive( struct gl_context *ctx, GLenum mode );
202 
203 extern void
204 _swrast_render_start( struct gl_context *ctx );
205 
206 extern void
207 _swrast_render_finish( struct gl_context *ctx );
208 
209 extern struct gl_texture_image *
210 _swrast_new_texture_image( struct gl_context *ctx );
211 
212 extern void
213 _swrast_delete_texture_image(struct gl_context *ctx,
214                              struct gl_texture_image *texImage);
215 
216 extern GLboolean
217 _swrast_alloc_texture_image_buffer(struct gl_context *ctx,
218                                    struct gl_texture_image *texImage);
219 
220 extern void
221 _swrast_init_texture_image(struct gl_texture_image *texImage);
222 
223 extern void
224 _swrast_free_texture_image_buffer(struct gl_context *ctx,
225                                   struct gl_texture_image *texImage);
226 
227 extern void
228 _swrast_map_teximage(struct gl_context *ctx,
229 		     struct gl_texture_image *texImage,
230 		     GLuint slice,
231 		     GLuint x, GLuint y, GLuint w, GLuint h,
232 		     GLbitfield mode,
233 		     GLubyte **mapOut,
234 		     GLint *rowStrideOut);
235 
236 extern void
237 _swrast_unmap_teximage(struct gl_context *ctx,
238 		       struct gl_texture_image *texImage,
239 		       GLuint slice);
240 
241 /* Tell the software rasterizer about core state changes.
242  */
243 extern void
244 _swrast_InvalidateState( struct gl_context *ctx, GLbitfield new_state );
245 
246 /* Configure software rasterizer to match hardware rasterizer characteristics:
247  */
248 extern void
249 _swrast_allow_vertex_fog( struct gl_context *ctx, GLboolean value );
250 
251 extern void
252 _swrast_allow_pixel_fog( struct gl_context *ctx, GLboolean value );
253 
254 /* Debug:
255  */
256 extern void
257 _swrast_print_vertex( struct gl_context *ctx, const SWvertex *v );
258 
259 
260 
261 extern void
262 _swrast_eject_texture_images(struct gl_context *ctx);
263 
264 
265 extern void
266 _swrast_render_texture(struct gl_context *ctx,
267                        struct gl_framebuffer *fb,
268                        struct gl_renderbuffer_attachment *att);
269 
270 extern void
271 _swrast_finish_render_texture(struct gl_context *ctx,
272                               struct gl_renderbuffer_attachment *att);
273 
274 
275 
276 extern GLboolean
277 _swrast_AllocTextureStorage(struct gl_context *ctx,
278                             struct gl_texture_object *texObj,
279                             GLsizei levels, GLsizei width,
280                             GLsizei height, GLsizei depth);
281 
282 
283 /**
284  * The driver interface for the software rasterizer.
285  * XXX this may go away.
286  * We may move these functions to ctx->Driver.RenderStart, RenderEnd.
287  */
288 struct swrast_device_driver {
289    /*
290     * These are called before and after accessing renderbuffers during
291     * software rasterization.
292     *
293     * These are a suitable place for grabbing/releasing hardware locks.
294     *
295     * NOTE: The swrast triangle/line/point routines *DO NOT* call
296     * these functions.  Locking in that case must be organized by the
297     * driver by other mechanisms.
298     */
299    void (*SpanRenderStart)(struct gl_context *ctx);
300    void (*SpanRenderFinish)(struct gl_context *ctx);
301 };
302 
303 
304 
305 #endif
306