1 /**************************************************************************
2 *
3 * Copyright 2007 VMware, Inc.
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 VMWARE 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 * glRasterPos implementation. Basically render a GL_POINT with our
30 * private draw module. Plug in a special "rasterpos" stage at the end
31 * of the 'draw' pipeline to capture the results and update the current
32 * raster pos attributes.
33 *
34 * Authors:
35 * Brian Paul
36 */
37
38
39
40 #include "main/macros.h"
41 #include "main/arrayobj.h"
42 #include "main/feedback.h"
43 #include "main/framebuffer.h"
44 #include "main/rastpos.h"
45 #include "main/state.h"
46 #include "main/varray.h"
47
48 #include "util/u_memory.h"
49
50 #include "st_context.h"
51 #include "st_atom.h"
52 #include "st_draw.h"
53 #include "st_program.h"
54 #include "st_cb_rasterpos.h"
55 #include "draw/draw_context.h"
56 #include "draw/draw_pipe.h"
57 #include "vbo/vbo.h"
58
59
60 /**
61 * Our special drawing pipeline stage (replaces rasterization).
62 */
63 struct rastpos_stage
64 {
65 struct draw_stage stage; /**< Base class */
66 struct gl_context *ctx; /**< Rendering context */
67
68 /* vertex attrib info we can setup once and re-use */
69 struct gl_vertex_array_object *VAO;
70 struct _mesa_prim prim;
71 };
72
73
74 static inline struct rastpos_stage *
rastpos_stage(struct draw_stage * stage)75 rastpos_stage( struct draw_stage *stage )
76 {
77 return (struct rastpos_stage *) stage;
78 }
79
80 static void
rastpos_flush(struct draw_stage * stage,unsigned flags)81 rastpos_flush( struct draw_stage *stage, unsigned flags )
82 {
83 /* no-op */
84 }
85
86 static void
rastpos_reset_stipple_counter(struct draw_stage * stage)87 rastpos_reset_stipple_counter( struct draw_stage *stage )
88 {
89 /* no-op */
90 }
91
92 static void
rastpos_tri(struct draw_stage * stage,struct prim_header * prim)93 rastpos_tri( struct draw_stage *stage, struct prim_header *prim )
94 {
95 /* should never get here */
96 assert(0);
97 }
98
99 static void
rastpos_line(struct draw_stage * stage,struct prim_header * prim)100 rastpos_line( struct draw_stage *stage, struct prim_header *prim )
101 {
102 /* should never get here */
103 assert(0);
104 }
105
106 static void
rastpos_destroy(struct draw_stage * stage)107 rastpos_destroy(struct draw_stage *stage)
108 {
109 struct rastpos_stage *rstage = (struct rastpos_stage*)stage;
110 _mesa_reference_vao(rstage->ctx, &rstage->VAO, NULL);
111 FREE(stage);
112 }
113
114
115 /**
116 * Update a raster pos attribute from the vertex result if it's present,
117 * else copy the current attrib.
118 */
119 static void
update_attrib(struct gl_context * ctx,const ubyte * outputMapping,const struct vertex_header * vert,GLfloat * dest,GLuint result,GLuint defaultAttrib)120 update_attrib(struct gl_context *ctx, const ubyte *outputMapping,
121 const struct vertex_header *vert,
122 GLfloat *dest,
123 GLuint result, GLuint defaultAttrib)
124 {
125 const GLfloat *src;
126 const ubyte k = outputMapping[result];
127 if (k != 0xff)
128 src = vert->data[k];
129 else
130 src = ctx->Current.Attrib[defaultAttrib];
131 COPY_4V(dest, src);
132 }
133
134
135 /**
136 * Normally, this function would render a GL_POINT.
137 */
138 static void
rastpos_point(struct draw_stage * stage,struct prim_header * prim)139 rastpos_point(struct draw_stage *stage, struct prim_header *prim)
140 {
141 struct rastpos_stage *rs = rastpos_stage(stage);
142 struct gl_context *ctx = rs->ctx;
143 struct st_context *st = st_context(ctx);
144 const GLfloat height = (GLfloat) ctx->DrawBuffer->Height;
145 struct gl_vertex_program *stvp = (struct gl_vertex_program *)st->vp;
146 const ubyte *outputMapping = stvp->result_to_output;
147 const GLfloat *pos;
148 GLuint i;
149
150 ctx->PopAttribState |= GL_CURRENT_BIT;
151
152 /* if we get here, we didn't get clipped */
153 ctx->Current.RasterPosValid = GL_TRUE;
154
155 /* update raster pos */
156 pos = prim->v[0]->data[0];
157 ctx->Current.RasterPos[0] = pos[0];
158 if (_mesa_fb_orientation(ctx->DrawBuffer) == Y_0_TOP)
159 ctx->Current.RasterPos[1] = height - pos[1]; /* invert Y */
160 else
161 ctx->Current.RasterPos[1] = pos[1];
162 ctx->Current.RasterPos[2] = pos[2];
163 ctx->Current.RasterPos[3] = pos[3];
164
165 /* update other raster attribs */
166 update_attrib(ctx, outputMapping, prim->v[0],
167 ctx->Current.RasterColor,
168 VARYING_SLOT_COL0, VERT_ATTRIB_COLOR0);
169
170 update_attrib(ctx, outputMapping, prim->v[0],
171 ctx->Current.RasterSecondaryColor,
172 VARYING_SLOT_COL1, VERT_ATTRIB_COLOR1);
173
174 for (i = 0; i < ctx->Const.MaxTextureCoordUnits; i++) {
175 update_attrib(ctx, outputMapping, prim->v[0],
176 ctx->Current.RasterTexCoords[i],
177 VARYING_SLOT_TEX0 + i, VERT_ATTRIB_TEX0 + i);
178 }
179
180 if (ctx->RenderMode == GL_SELECT) {
181 _mesa_update_hitflag( ctx, ctx->Current.RasterPos[2] );
182 }
183 }
184
185
186 /**
187 * Create rasterpos "drawing" stage.
188 */
189 static struct rastpos_stage *
new_draw_rastpos_stage(struct gl_context * ctx,struct draw_context * draw)190 new_draw_rastpos_stage(struct gl_context *ctx, struct draw_context *draw)
191 {
192 struct rastpos_stage *rs = CALLOC_STRUCT(rastpos_stage);
193
194 rs->stage.draw = draw;
195 rs->stage.next = NULL;
196 rs->stage.point = rastpos_point;
197 rs->stage.line = rastpos_line;
198 rs->stage.tri = rastpos_tri;
199 rs->stage.flush = rastpos_flush;
200 rs->stage.destroy = rastpos_destroy;
201 rs->stage.reset_stipple_counter = rastpos_reset_stipple_counter;
202 rs->stage.destroy = rastpos_destroy;
203 rs->ctx = ctx;
204
205 rs->VAO = _mesa_new_vao(ctx, ~((GLuint)0));
206 _mesa_vertex_attrib_binding(ctx, rs->VAO, VERT_ATTRIB_POS, 0);
207 _mesa_update_array_format(ctx, rs->VAO, VERT_ATTRIB_POS, 4, GL_FLOAT,
208 GL_RGBA, GL_FALSE, GL_FALSE, GL_FALSE, 0);
209 _mesa_enable_vertex_array_attrib(ctx, rs->VAO, 0);
210
211 rs->prim.mode = GL_POINTS;
212 rs->prim.begin = 1;
213 rs->prim.end = 1;
214 rs->prim.start = 0;
215 rs->prim.count = 1;
216
217 return rs;
218 }
219
220
221 void
st_RasterPos(struct gl_context * ctx,const GLfloat v[4])222 st_RasterPos(struct gl_context *ctx, const GLfloat v[4])
223 {
224 struct st_context *st = st_context(ctx);
225 struct draw_context *draw = st_get_draw_context(st);
226 struct rastpos_stage *rs;
227
228 if (!st->draw)
229 return;
230
231 if (ctx->VertexProgram._Current == NULL ||
232 ctx->VertexProgram._Current == ctx->VertexProgram._TnlProgram) {
233 /* No vertex shader/program is enabled, used the simple/fast fixed-
234 * function implementation of RasterPos.
235 */
236 _mesa_RasterPos(ctx, v);
237 return;
238 }
239
240 if (st->rastpos_stage) {
241 /* get rastpos stage info */
242 rs = rastpos_stage(st->rastpos_stage);
243 }
244 else {
245 /* create rastpos draw stage */
246 rs = new_draw_rastpos_stage(ctx, draw);
247 st->rastpos_stage = &rs->stage;
248 }
249
250 /* plug our rastpos stage into the draw module */
251 draw_set_rasterize_stage(st->draw, st->rastpos_stage);
252
253 /* make sure everything's up to date */
254 st_validate_state(st, ST_PIPELINE_RENDER);
255
256 /* This will get set only if rastpos_point(), above, gets called */
257 ctx->PopAttribState |= GL_CURRENT_BIT;
258 ctx->Current.RasterPosValid = GL_FALSE;
259
260 /* All vertex attribs but position were previously initialized above.
261 * Just plug in position pointer now.
262 */
263 rs->VAO->VertexAttrib[VERT_ATTRIB_POS].Ptr = (GLubyte *) v;
264 rs->VAO->NewVertexBuffers = true;
265 /* Non-dynamic VAOs merge vertex buffers, which changes vertex elements. */
266 if (!rs->VAO->IsDynamic)
267 rs->VAO->NewVertexElements = true;
268 _mesa_set_draw_vao(ctx, rs->VAO, VERT_BIT_POS);
269
270 /* Draw the point. */
271 st_feedback_draw_vbo(ctx, &rs->prim, 1, NULL, true, false, 0, 0, 1, 1, 0);
272
273 /* restore draw's rasterization stage depending on rendermode */
274 if (ctx->RenderMode == GL_FEEDBACK) {
275 draw_set_rasterize_stage(draw, st->feedback_stage);
276 }
277 else if (ctx->RenderMode == GL_SELECT) {
278 draw_set_rasterize_stage(draw, st->selection_stage);
279 }
280 }
281