2 * Mesa 3-D graphics library
5 * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
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:
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
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.
26 #include "main/glheader.h"
27 #include "main/colormac.h"
28 #include "main/macros.h"
29 #include "s_context.h"
30 #include "s_feedback.h"
36 * Used to cull points with invalid coords
38 #define CULL_INVALID(V) \
40 float tmp = (V)->attrib[FRAG_ATTRIB_WPOS][0] \
41 + (V)->attrib[FRAG_ATTRIB_WPOS][1]; \
42 if (IS_INF_OR_NAN(tmp)) \
49 * Get/compute the point size.
50 * The size may come from a vertex shader, or computed with attentuation
51 * or just the glPointSize value.
52 * Must also clamp to user-defined range and implmentation limits.
55 get_size(const struct gl_context
*ctx
, const SWvertex
*vert
, GLboolean smoothed
)
59 if (ctx
->Point
._Attenuated
|| ctx
->VertexProgram
.PointSizeEnabled
) {
60 /* use vertex's point size */
61 size
= vert
->pointSize
;
64 /* use constant point size */
65 size
= ctx
->Point
.Size
;
67 /* always clamp to user-specified limits */
68 size
= CLAMP(size
, ctx
->Point
.MinSize
, ctx
->Point
.MaxSize
);
69 /* clamp to implementation limits */
71 size
= CLAMP(size
, ctx
->Const
.MinPointSizeAA
, ctx
->Const
.MaxPointSizeAA
);
73 size
= CLAMP(size
, ctx
->Const
.MinPointSize
, ctx
->Const
.MaxPointSize
);
83 sprite_point(struct gl_context
*ctx
, const SWvertex
*vert
)
85 SWcontext
*swrast
= SWRAST_CONTEXT(ctx
);
88 GLuint tCoords
[MAX_TEXTURE_COORD_UNITS
+ 1];
89 GLuint numTcoords
= 0;
95 if (ctx
->DrawBuffer
->Visual
.depthBits
<= 16)
96 span
.z
= FloatToFixed(vert
->attrib
[FRAG_ATTRIB_WPOS
][2] + 0.5F
);
98 span
.z
= (GLuint
) (vert
->attrib
[FRAG_ATTRIB_WPOS
][2] + 0.5F
);
101 size
= get_size(ctx
, vert
, GL_FALSE
);
104 INIT_SPAN(span
, GL_POINT
);
105 span
.interpMask
= SPAN_Z
| SPAN_RGBA
;
107 span
.facing
= swrast
->PointLineFacing
;
109 span
.red
= ChanToFixed(vert
->color
[0]);
110 span
.green
= ChanToFixed(vert
->color
[1]);
111 span
.blue
= ChanToFixed(vert
->color
[2]);
112 span
.alpha
= ChanToFixed(vert
->color
[3]);
118 /* need these for fragment programs */
119 span
.attrStart
[FRAG_ATTRIB_WPOS
][3] = 1.0F
;
120 span
.attrStepX
[FRAG_ATTRIB_WPOS
][3] = 0.0F
;
121 span
.attrStepY
[FRAG_ATTRIB_WPOS
][3] = 0.0F
;
126 /* texcoord / pointcoord interpolants */
129 if (ctx
->Point
.SpriteOrigin
== GL_LOWER_LEFT
) {
136 t0
= 1.0F
+ 0.5F
* dtdy
;
140 if (attr
>= FRAG_ATTRIB_TEX0
&& attr
<= FRAG_ATTRIB_TEX7
) {
141 /* a texcoord attribute */
142 const GLuint u
= attr
- FRAG_ATTRIB_TEX0
;
143 ASSERT(u
< Elements(ctx
->Point
.CoordReplace
));
144 if (ctx
->Point
.CoordReplace
[u
]) {
145 tCoords
[numTcoords
++] = attr
;
147 if (ctx
->Point
.SpriteRMode
== GL_ZERO
)
149 else if (ctx
->Point
.SpriteRMode
== GL_S
)
150 r
= vert
->attrib
[attr
][0];
152 r
= vert
->attrib
[attr
][2];
154 span
.attrStart
[attr
][0] = s
;
155 span
.attrStart
[attr
][1] = 0.0; /* overwritten below */
156 span
.attrStart
[attr
][2] = r
;
157 span
.attrStart
[attr
][3] = 1.0;
159 span
.attrStepX
[attr
][0] = dsdx
;
160 span
.attrStepX
[attr
][1] = 0.0;
161 span
.attrStepX
[attr
][2] = 0.0;
162 span
.attrStepX
[attr
][3] = 0.0;
164 span
.attrStepY
[attr
][0] = 0.0;
165 span
.attrStepY
[attr
][1] = dtdy
;
166 span
.attrStepY
[attr
][2] = 0.0;
167 span
.attrStepY
[attr
][3] = 0.0;
172 else if (attr
== FRAG_ATTRIB_PNTC
) {
173 /* GLSL gl_PointCoord.xy (.zw undefined) */
174 span
.attrStart
[FRAG_ATTRIB_PNTC
][0] = 0.0;
175 span
.attrStart
[FRAG_ATTRIB_PNTC
][1] = 0.0; /* t0 set below */
176 span
.attrStepX
[FRAG_ATTRIB_PNTC
][0] = dsdx
;
177 span
.attrStepX
[FRAG_ATTRIB_PNTC
][1] = 0.0;
178 span
.attrStepY
[FRAG_ATTRIB_PNTC
][0] = 0.0;
179 span
.attrStepY
[FRAG_ATTRIB_PNTC
][1] = dtdy
;
180 tCoords
[numTcoords
++] = FRAG_ATTRIB_PNTC
;
183 /* use vertex's texcoord/attrib */
184 COPY_4V(span
.attrStart
[attr
], vert
->attrib
[attr
]);
185 ASSIGN_4V(span
.attrStepX
[attr
], 0, 0, 0, 0);
186 ASSIGN_4V(span
.attrStepY
[attr
], 0, 0, 0, 0);
190 /* compute pos, bounds and render */
192 const GLfloat x
= vert
->attrib
[FRAG_ATTRIB_WPOS
][0];
193 const GLfloat y
= vert
->attrib
[FRAG_ATTRIB_WPOS
][1];
194 GLint iSize
= (GLint
) (size
+ 0.5F
);
195 GLint xmin
, xmax
, ymin
, ymax
, iy
;
199 iSize
= MAX2(1, iSize
);
204 xmin
= (GLint
) (x
- iRadius
);
205 xmax
= (GLint
) (x
+ iRadius
);
206 ymin
= (GLint
) (y
- iRadius
);
207 ymax
= (GLint
) (y
+ iRadius
);
211 /* 0.501 factor allows conformance to pass */
212 xmin
= (GLint
) (x
+ 0.501) - iRadius
;
213 xmax
= xmin
+ iSize
- 1;
214 ymin
= (GLint
) (y
+ 0.501) - iRadius
;
215 ymax
= ymin
+ iSize
- 1;
219 for (iy
= ymin
; iy
<= ymax
; iy
++) {
221 /* setup texcoord T for this row */
222 for (i
= 0; i
< numTcoords
; i
++) {
223 span
.attrStart
[tCoords
[i
]][1] = tcoord
;
226 /* these might get changed by span clipping */
229 span
.end
= xmax
- xmin
+ 1;
231 _swrast_write_rgba_span(ctx
, &span
);
240 * Draw smooth/antialiased point. RGB or CI mode.
243 smooth_point(struct gl_context
*ctx
, const SWvertex
*vert
)
245 SWcontext
*swrast
= SWRAST_CONTEXT(ctx
);
247 GLfloat size
, alphaAtten
;
252 if (ctx
->DrawBuffer
->Visual
.depthBits
<= 16)
253 span
.z
= FloatToFixed(vert
->attrib
[FRAG_ATTRIB_WPOS
][2] + 0.5F
);
255 span
.z
= (GLuint
) (vert
->attrib
[FRAG_ATTRIB_WPOS
][2] + 0.5F
);
258 size
= get_size(ctx
, vert
, GL_TRUE
);
260 /* alpha attenuation / fade factor */
261 if (ctx
->Multisample
._Enabled
) {
262 if (vert
->pointSize
>= ctx
->Point
.Threshold
) {
266 GLfloat dsize
= vert
->pointSize
/ ctx
->Point
.Threshold
;
267 alphaAtten
= dsize
* dsize
;
273 (void) alphaAtten
; /* not used */
276 INIT_SPAN(span
, GL_POINT
);
277 span
.interpMask
= SPAN_Z
| SPAN_RGBA
;
278 span
.arrayMask
= SPAN_COVERAGE
| SPAN_MASK
;
280 span
.facing
= swrast
->PointLineFacing
;
282 span
.red
= ChanToFixed(vert
->color
[0]);
283 span
.green
= ChanToFixed(vert
->color
[1]);
284 span
.blue
= ChanToFixed(vert
->color
[2]);
285 span
.alpha
= ChanToFixed(vert
->color
[3]);
291 /* need these for fragment programs */
292 span
.attrStart
[FRAG_ATTRIB_WPOS
][3] = 1.0F
;
293 span
.attrStepX
[FRAG_ATTRIB_WPOS
][3] = 0.0F
;
294 span
.attrStepY
[FRAG_ATTRIB_WPOS
][3] = 0.0F
;
297 COPY_4V(span
.attrStart
[attr
], vert
->attrib
[attr
]);
298 ASSIGN_4V(span
.attrStepX
[attr
], 0, 0, 0, 0);
299 ASSIGN_4V(span
.attrStepY
[attr
], 0, 0, 0, 0);
302 /* compute pos, bounds and render */
304 const GLfloat x
= vert
->attrib
[FRAG_ATTRIB_WPOS
][0];
305 const GLfloat y
= vert
->attrib
[FRAG_ATTRIB_WPOS
][1];
306 const GLfloat radius
= 0.5F
* size
;
307 const GLfloat rmin
= radius
- 0.7071F
; /* 0.7071 = sqrt(2)/2 */
308 const GLfloat rmax
= radius
+ 0.7071F
;
309 const GLfloat rmin2
= MAX2(0.0F
, rmin
* rmin
);
310 const GLfloat rmax2
= rmax
* rmax
;
311 const GLfloat cscale
= 1.0F
/ (rmax2
- rmin2
);
312 const GLint xmin
= (GLint
) (x
- radius
);
313 const GLint xmax
= (GLint
) (x
+ radius
);
314 const GLint ymin
= (GLint
) (y
- radius
);
315 const GLint ymax
= (GLint
) (y
+ radius
);
318 for (iy
= ymin
; iy
<= ymax
; iy
++) {
320 /* these might get changed by span clipping */
323 span
.end
= xmax
- xmin
+ 1;
325 /* compute coverage for each pixel in span */
326 for (ix
= xmin
; ix
<= xmax
; ix
++) {
327 const GLfloat dx
= ix
- x
+ 0.5F
;
328 const GLfloat dy
= iy
- y
+ 0.5F
;
329 const GLfloat dist2
= dx
* dx
+ dy
* dy
;
333 if (dist2
>= rmin2
) {
334 /* compute partial coverage */
335 coverage
= 1.0F
- (dist2
- rmin2
) * cscale
;
341 span
.array
->mask
[ix
- xmin
] = 1;
344 /* zero coverage - fragment outside the radius */
346 span
.array
->mask
[ix
- xmin
] = 0;
348 span
.array
->coverage
[ix
- xmin
] = coverage
;
352 _swrast_write_rgba_span(ctx
, &span
);
360 * Draw large (size >= 1) non-AA point. RGB or CI mode.
363 large_point(struct gl_context
*ctx
, const SWvertex
*vert
)
365 SWcontext
*swrast
= SWRAST_CONTEXT(ctx
);
372 if (ctx
->DrawBuffer
->Visual
.depthBits
<= 16)
373 span
.z
= FloatToFixed(vert
->attrib
[FRAG_ATTRIB_WPOS
][2] + 0.5F
);
375 span
.z
= (GLuint
) (vert
->attrib
[FRAG_ATTRIB_WPOS
][2] + 0.5F
);
378 size
= get_size(ctx
, vert
, GL_FALSE
);
381 INIT_SPAN(span
, GL_POINT
);
382 span
.arrayMask
= SPAN_XY
;
383 span
.facing
= swrast
->PointLineFacing
;
385 span
.interpMask
= SPAN_Z
| SPAN_RGBA
;
386 span
.red
= ChanToFixed(vert
->color
[0]);
387 span
.green
= ChanToFixed(vert
->color
[1]);
388 span
.blue
= ChanToFixed(vert
->color
[2]);
389 span
.alpha
= ChanToFixed(vert
->color
[3]);
395 /* need these for fragment programs */
396 span
.attrStart
[FRAG_ATTRIB_WPOS
][3] = 1.0F
;
397 span
.attrStepX
[FRAG_ATTRIB_WPOS
][3] = 0.0F
;
398 span
.attrStepY
[FRAG_ATTRIB_WPOS
][3] = 0.0F
;
401 COPY_4V(span
.attrStart
[attr
], vert
->attrib
[attr
]);
402 ASSIGN_4V(span
.attrStepX
[attr
], 0, 0, 0, 0);
403 ASSIGN_4V(span
.attrStepY
[attr
], 0, 0, 0, 0);
406 /* compute pos, bounds and render */
408 const GLfloat x
= vert
->attrib
[FRAG_ATTRIB_WPOS
][0];
409 const GLfloat y
= vert
->attrib
[FRAG_ATTRIB_WPOS
][1];
410 GLint iSize
= (GLint
) (size
+ 0.5F
);
411 GLint xmin
, xmax
, ymin
, ymax
, ix
, iy
;
414 iSize
= MAX2(1, iSize
);
419 xmin
= (GLint
) (x
- iRadius
);
420 xmax
= (GLint
) (x
+ iRadius
);
421 ymin
= (GLint
) (y
- iRadius
);
422 ymax
= (GLint
) (y
+ iRadius
);
426 /* 0.501 factor allows conformance to pass */
427 xmin
= (GLint
) (x
+ 0.501) - iRadius
;
428 xmax
= xmin
+ iSize
- 1;
429 ymin
= (GLint
) (y
+ 0.501) - iRadius
;
430 ymax
= ymin
+ iSize
- 1;
433 /* generate fragments */
435 for (iy
= ymin
; iy
<= ymax
; iy
++) {
436 for (ix
= xmin
; ix
<= xmax
; ix
++) {
437 span
.array
->x
[span
.end
] = ix
;
438 span
.array
->y
[span
.end
] = iy
;
442 assert(span
.end
<= MAX_WIDTH
);
443 _swrast_write_rgba_span(ctx
, &span
);
449 * Draw size=1, single-pixel point
452 pixel_point(struct gl_context
*ctx
, const SWvertex
*vert
)
454 SWcontext
*swrast
= SWRAST_CONTEXT(ctx
);
456 * Note that unlike the other functions, we put single-pixel points
457 * into a special span array in order to render as many points as
458 * possible with a single _swrast_write_rgba_span() call.
460 SWspan
*span
= &(swrast
->PointSpan
);
466 span
->interpMask
= 0;
467 span
->arrayMask
= SPAN_XY
| SPAN_Z
;
468 span
->arrayMask
|= SPAN_RGBA
;
469 /*span->arrayMask |= SPAN_LAMBDA;*/
470 span
->arrayAttribs
= swrast
->_ActiveAttribMask
; /* we'll produce these vals */
472 /* need these for fragment programs */
473 span
->attrStart
[FRAG_ATTRIB_WPOS
][3] = 1.0F
;
474 span
->attrStepX
[FRAG_ATTRIB_WPOS
][3] = 0.0F
;
475 span
->attrStepY
[FRAG_ATTRIB_WPOS
][3] = 0.0F
;
477 /* check if we need to flush */
478 if (span
->end
>= MAX_WIDTH
||
479 (swrast
->_RasterMask
& (BLEND_BIT
| LOGIC_OP_BIT
| MASKING_BIT
)) ||
480 span
->facing
!= swrast
->PointLineFacing
) {
482 _swrast_write_rgba_span(ctx
, span
);
489 span
->facing
= swrast
->PointLineFacing
;
491 /* fragment attributes */
492 span
->array
->rgba
[count
][RCOMP
] = vert
->color
[0];
493 span
->array
->rgba
[count
][GCOMP
] = vert
->color
[1];
494 span
->array
->rgba
[count
][BCOMP
] = vert
->color
[2];
495 span
->array
->rgba
[count
][ACOMP
] = vert
->color
[3];
498 COPY_4V(span
->array
->attribs
[attr
][count
], vert
->attrib
[attr
]);
501 /* fragment position */
502 span
->array
->x
[count
] = (GLint
) vert
->attrib
[FRAG_ATTRIB_WPOS
][0];
503 span
->array
->y
[count
] = (GLint
) vert
->attrib
[FRAG_ATTRIB_WPOS
][1];
504 span
->array
->z
[count
] = (GLint
) (vert
->attrib
[FRAG_ATTRIB_WPOS
][2] + 0.5F
);
506 span
->end
= count
+ 1;
507 ASSERT(span
->end
<= MAX_WIDTH
);
512 * Add specular color to primary color, draw point, restore original
516 _swrast_add_spec_terms_point(struct gl_context
*ctx
, const SWvertex
*v0
)
518 SWvertex
*ncv0
= (SWvertex
*) v0
; /* cast away const */
519 GLfloat rSum
, gSum
, bSum
;
523 COPY_CHAN4(cSave
, ncv0
->color
);
525 rSum
= CHAN_TO_FLOAT(ncv0
->color
[0]) + ncv0
->attrib
[FRAG_ATTRIB_COL1
][0];
526 gSum
= CHAN_TO_FLOAT(ncv0
->color
[1]) + ncv0
->attrib
[FRAG_ATTRIB_COL1
][1];
527 bSum
= CHAN_TO_FLOAT(ncv0
->color
[2]) + ncv0
->attrib
[FRAG_ATTRIB_COL1
][2];
528 UNCLAMPED_FLOAT_TO_CHAN(ncv0
->color
[0], rSum
);
529 UNCLAMPED_FLOAT_TO_CHAN(ncv0
->color
[1], gSum
);
530 UNCLAMPED_FLOAT_TO_CHAN(ncv0
->color
[2], bSum
);
532 SWRAST_CONTEXT(ctx
)->SpecPoint(ctx
, ncv0
);
534 COPY_CHAN4(ncv0
->color
, cSave
);
539 * Examine current state to determine which point drawing function to use.
542 _swrast_choose_point(struct gl_context
*ctx
)
544 SWcontext
*swrast
= SWRAST_CONTEXT(ctx
);
545 const GLfloat size
= CLAMP(ctx
->Point
.Size
,
549 if (ctx
->RenderMode
== GL_RENDER
) {
550 if (ctx
->Point
.PointSprite
) {
551 swrast
->Point
= sprite_point
;
553 else if (ctx
->Point
.SmoothFlag
) {
554 swrast
->Point
= smooth_point
;
556 else if (size
> 1.0 ||
557 ctx
->Point
._Attenuated
||
558 ctx
->VertexProgram
.PointSizeEnabled
) {
559 swrast
->Point
= large_point
;
562 swrast
->Point
= pixel_point
;
565 else if (ctx
->RenderMode
== GL_FEEDBACK
) {
566 swrast
->Point
= _swrast_feedback_point
;
570 swrast
->Point
= _swrast_select_point
;