1 /*-------------------------------------------------------------------------
2 * drawElements Quality Program Reference Renderer
3 * -----------------------------------------------
4 *
5 * Copyright 2014 The Android Open Source Project
6 *
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 *
19 *//*!
20 * \file
21 * \brief Reference rasterizer
22 *//*--------------------------------------------------------------------*/
23
24 #include "rrRasterizer.hpp"
25 #include "deMath.h"
26 #include "tcuVectorUtil.hpp"
27
28 namespace rr
29 {
30
toSubpixelCoord(float v)31 inline deInt64 toSubpixelCoord (float v)
32 {
33 return (deInt64)(v * (1<<RASTERIZER_SUBPIXEL_BITS) + (v < 0.f ? -0.5f : 0.5f));
34 }
35
toSubpixelCoord(deInt32 v)36 inline deInt64 toSubpixelCoord (deInt32 v)
37 {
38 return v << RASTERIZER_SUBPIXEL_BITS;
39 }
40
ceilSubpixelToPixelCoord(deInt64 coord,bool fillEdge)41 inline deInt32 ceilSubpixelToPixelCoord (deInt64 coord, bool fillEdge)
42 {
43 if (coord >= 0)
44 return (deInt32)((coord + ((1ll<<RASTERIZER_SUBPIXEL_BITS) - (fillEdge ? 0 : 1))) >> RASTERIZER_SUBPIXEL_BITS);
45 else
46 return (deInt32)((coord + (fillEdge ? 1 : 0)) >> RASTERIZER_SUBPIXEL_BITS);
47 }
48
floorSubpixelToPixelCoord(deInt64 coord,bool fillEdge)49 inline deInt32 floorSubpixelToPixelCoord (deInt64 coord, bool fillEdge)
50 {
51 if (coord >= 0)
52 return (deInt32)((coord - (fillEdge ? 1 : 0)) >> RASTERIZER_SUBPIXEL_BITS);
53 else
54 return (deInt32)((coord - ((1ll<<RASTERIZER_SUBPIXEL_BITS) - (fillEdge ? 0 : 1))) >> RASTERIZER_SUBPIXEL_BITS);
55 }
56
initEdgeCCW(EdgeFunction & edge,const HorizontalFill horizontalFill,const VerticalFill verticalFill,const deInt64 x0,const deInt64 y0,const deInt64 x1,const deInt64 y1)57 static inline void initEdgeCCW (EdgeFunction& edge, const HorizontalFill horizontalFill, const VerticalFill verticalFill, const deInt64 x0, const deInt64 y0, const deInt64 x1, const deInt64 y1)
58 {
59 // \note See EdgeFunction documentation for details.
60
61 const deInt64 xd = x1-x0;
62 const deInt64 yd = y1-y0;
63 bool inclusive = false; //!< Inclusive in CCW orientation.
64
65 if (yd == 0)
66 inclusive = verticalFill == FILL_BOTTOM ? xd >= 0 : xd <= 0;
67 else
68 inclusive = horizontalFill == FILL_LEFT ? yd <= 0 : yd >= 0;
69
70 edge.a = (y0 - y1);
71 edge.b = (x1 - x0);
72 edge.c = x0*y1 - y0*x1;
73 edge.inclusive = inclusive; //!< \todo [pyry] Swap for CW triangles
74 }
75
reverseEdge(EdgeFunction & edge)76 static inline void reverseEdge (EdgeFunction& edge)
77 {
78 edge.a = -edge.a;
79 edge.b = -edge.b;
80 edge.c = -edge.c;
81 edge.inclusive = !edge.inclusive;
82 }
83
evaluateEdge(const EdgeFunction & edge,const deInt64 x,const deInt64 y)84 static inline deInt64 evaluateEdge (const EdgeFunction& edge, const deInt64 x, const deInt64 y)
85 {
86 return edge.a*x + edge.b*y + edge.c;
87 }
88
isInsideCCW(const EdgeFunction & edge,const deInt64 edgeVal)89 static inline bool isInsideCCW (const EdgeFunction& edge, const deInt64 edgeVal)
90 {
91 return edge.inclusive ? (edgeVal >= 0) : (edgeVal > 0);
92 }
93
94 namespace LineRasterUtil
95 {
96
97 struct SubpixelLineSegment
98 {
99 const tcu::Vector<deInt64,2> m_v0;
100 const tcu::Vector<deInt64,2> m_v1;
101
SubpixelLineSegmentrr::LineRasterUtil::SubpixelLineSegment102 SubpixelLineSegment (const tcu::Vector<deInt64,2>& v0, const tcu::Vector<deInt64,2>& v1)
103 : m_v0(v0)
104 , m_v1(v1)
105 {
106 }
107
directionrr::LineRasterUtil::SubpixelLineSegment108 tcu::Vector<deInt64,2> direction (void) const
109 {
110 return m_v1 - m_v0;
111 }
112 };
113
114 enum LINE_SIDE
115 {
116 LINE_SIDE_INTERSECT = 0,
117 LINE_SIDE_LEFT,
118 LINE_SIDE_RIGHT
119 };
120
toSubpixelVector(const tcu::Vec2 & v)121 static tcu::Vector<deInt64,2> toSubpixelVector (const tcu::Vec2& v)
122 {
123 return tcu::Vector<deInt64,2>(toSubpixelCoord(v.x()), toSubpixelCoord(v.y()));
124 }
125
toSubpixelVector(const tcu::IVec2 & v)126 static tcu::Vector<deInt64,2> toSubpixelVector (const tcu::IVec2& v)
127 {
128 return tcu::Vector<deInt64,2>(toSubpixelCoord(v.x()), toSubpixelCoord(v.y()));
129 }
130
131 #if defined(DE_DEBUG)
isTheCenterOfTheFragment(const tcu::Vector<deInt64,2> & a)132 static bool isTheCenterOfTheFragment (const tcu::Vector<deInt64,2>& a)
133 {
134 const deUint64 pixelSize = 1ll << (RASTERIZER_SUBPIXEL_BITS);
135 const deUint64 halfPixel = 1ll << (RASTERIZER_SUBPIXEL_BITS-1);
136 return ((a.x() & (pixelSize-1)) == halfPixel &&
137 (a.y() & (pixelSize-1)) == halfPixel);
138 }
139
inViewport(const tcu::IVec2 & p,const tcu::IVec4 & viewport)140 static bool inViewport (const tcu::IVec2& p, const tcu::IVec4& viewport)
141 {
142 return p.x() >= viewport.x() &&
143 p.y() >= viewport.y() &&
144 p.x() < viewport.x() + viewport.z() &&
145 p.y() < viewport.y() + viewport.w();
146 }
147 #endif // DE_DEBUG
148
149 // returns true if vertex is on the left side of the line
vertexOnLeftSideOfLine(const tcu::Vector<deInt64,2> & p,const SubpixelLineSegment & l)150 static bool vertexOnLeftSideOfLine (const tcu::Vector<deInt64,2>& p, const SubpixelLineSegment& l)
151 {
152 const tcu::Vector<deInt64,2> u = l.direction();
153 const tcu::Vector<deInt64,2> v = ( p - l.m_v0);
154 const deInt64 crossProduct = (u.x() * v.y() - u.y() * v.x());
155 return crossProduct < 0;
156 }
157
158 // returns true if vertex is on the right side of the line
vertexOnRightSideOfLine(const tcu::Vector<deInt64,2> & p,const SubpixelLineSegment & l)159 static bool vertexOnRightSideOfLine (const tcu::Vector<deInt64,2>& p, const SubpixelLineSegment& l)
160 {
161 const tcu::Vector<deInt64,2> u = l.direction();
162 const tcu::Vector<deInt64,2> v = ( p - l.m_v0);
163 const deInt64 crossProduct = (u.x() * v.y() - u.y() * v.x());
164 return crossProduct > 0;
165 }
166
167 // returns true if vertex is on the line
vertexOnLine(const tcu::Vector<deInt64,2> & p,const SubpixelLineSegment & l)168 static bool vertexOnLine (const tcu::Vector<deInt64,2>& p, const SubpixelLineSegment& l)
169 {
170 const tcu::Vector<deInt64,2> u = l.direction();
171 const tcu::Vector<deInt64,2> v = ( p - l.m_v0);
172 const deInt64 crossProduct = (u.x() * v.y() - u.y() * v.x());
173 return crossProduct == 0; // cross product == 0
174 }
175
176 // returns true if vertex is on the line segment
vertexOnLineSegment(const tcu::Vector<deInt64,2> & p,const SubpixelLineSegment & l)177 static bool vertexOnLineSegment (const tcu::Vector<deInt64,2>& p, const SubpixelLineSegment& l)
178 {
179 if (!vertexOnLine(p, l))
180 return false;
181
182 const tcu::Vector<deInt64,2> v = l.direction();
183 const tcu::Vector<deInt64,2> u1 = ( p - l.m_v0);
184 const tcu::Vector<deInt64,2> u2 = ( p - l.m_v1);
185
186 if (v.x() == 0 && v.y() == 0)
187 return false;
188
189 return tcu::dot( v, u1) >= 0 &&
190 tcu::dot(-v, u2) >= 0; // dot (A->B, A->V) >= 0 and dot (B->A, B->V) >= 0
191 }
192
getVertexSide(const tcu::Vector<deInt64,2> & v,const SubpixelLineSegment & l)193 static LINE_SIDE getVertexSide (const tcu::Vector<deInt64,2>& v, const SubpixelLineSegment& l)
194 {
195 if (vertexOnLeftSideOfLine(v, l))
196 return LINE_SIDE_LEFT;
197 else if (vertexOnRightSideOfLine(v, l))
198 return LINE_SIDE_RIGHT;
199 else if (vertexOnLine(v, l))
200 return LINE_SIDE_INTERSECT;
201 else
202 {
203 DE_ASSERT(false);
204 return LINE_SIDE_INTERSECT;
205 }
206 }
207
208 // returns true if angle between line and given cornerExitNormal is in range (-45, 45)
lineInCornerAngleRange(const SubpixelLineSegment & line,const tcu::Vector<deInt64,2> & cornerExitNormal)209 bool lineInCornerAngleRange (const SubpixelLineSegment& line, const tcu::Vector<deInt64,2>& cornerExitNormal)
210 {
211 // v0 -> v1 has angle difference to cornerExitNormal in range (-45, 45)
212 const tcu::Vector<deInt64,2> v = line.direction();
213 const deInt64 dotProduct = dot(v, cornerExitNormal);
214
215 // dotProduct > |v1-v0|*|cornerExitNormal|/sqrt(2)
216 if (dotProduct < 0)
217 return false;
218 return 2 * dotProduct * dotProduct > tcu::lengthSquared(v)*tcu::lengthSquared(cornerExitNormal);
219 }
220
221 // returns true if angle between line and given cornerExitNormal is in range (-135, 135)
lineInCornerOutsideAngleRange(const SubpixelLineSegment & line,const tcu::Vector<deInt64,2> & cornerExitNormal)222 bool lineInCornerOutsideAngleRange (const SubpixelLineSegment& line, const tcu::Vector<deInt64,2>& cornerExitNormal)
223 {
224 // v0 -> v1 has angle difference to cornerExitNormal in range (-135, 135)
225 const tcu::Vector<deInt64,2> v = line.direction();
226 const deInt64 dotProduct = dot(v, cornerExitNormal);
227
228 // dotProduct > -|v1-v0|*|cornerExitNormal|/sqrt(2)
229 if (dotProduct >= 0)
230 return true;
231 return 2 * (-dotProduct) * (-dotProduct) < tcu::lengthSquared(v)*tcu::lengthSquared(cornerExitNormal);
232 }
233
doesLineSegmentExitDiamond(const SubpixelLineSegment & line,const tcu::Vector<deInt64,2> & diamondCenter)234 bool doesLineSegmentExitDiamond (const SubpixelLineSegment& line, const tcu::Vector<deInt64,2>& diamondCenter)
235 {
236 DE_ASSERT(isTheCenterOfTheFragment(diamondCenter));
237
238 // Diamond Center is at diamondCenter in subpixel coords
239
240 const deInt64 halfPixel = 1ll << (RASTERIZER_SUBPIXEL_BITS-1);
241
242 // Reject distant diamonds early
243 {
244 const tcu::Vector<deInt64,2> u = line.direction();
245 const tcu::Vector<deInt64,2> v = (diamondCenter - line.m_v0);
246 const deInt64 crossProduct = (u.x() * v.y() - u.y() * v.x());
247
248 // crossProduct = |p| |l| sin(theta)
249 // distanceFromLine = |p| sin(theta)
250 // => distanceFromLine = crossProduct / |l|
251 //
252 // |distanceFromLine| > C
253 // => distanceFromLine^2 > C^2
254 // => crossProduct^2 / |l|^2 > C^2
255 // => crossProduct^2 > |l|^2 * C^2
256
257 const deInt64 floorSqrtMaxInt64 = 3037000499LL; //!< floor(sqrt(MAX_INT64))
258
259 const deInt64 broadRejectDistance = 2 * halfPixel;
260 const deInt64 broadRejectDistanceSquared = broadRejectDistance * broadRejectDistance;
261 const bool crossProductOverflows = (crossProduct > floorSqrtMaxInt64 || crossProduct < -floorSqrtMaxInt64);
262 const deInt64 crossProductSquared = (crossProductOverflows) ? (0) : (crossProduct * crossProduct); // avoid overflow
263 const deInt64 lineLengthSquared = tcu::lengthSquared(u);
264 const bool limitValueCouldOverflow = ((64 - deClz64(lineLengthSquared)) + (64 - deClz64(broadRejectDistanceSquared))) > 63;
265 const deInt64 limitValue = (limitValueCouldOverflow) ? (0) : (lineLengthSquared * broadRejectDistanceSquared); // avoid overflow
266
267 // only cross overflows
268 if (crossProductOverflows && !limitValueCouldOverflow)
269 return false;
270
271 // both representable
272 if (!crossProductOverflows && !limitValueCouldOverflow)
273 {
274 if (crossProductSquared > limitValue)
275 return false;
276 }
277 }
278
279 const struct DiamondBound
280 {
281 tcu::Vector<deInt64,2> p0;
282 tcu::Vector<deInt64,2> p1;
283 bool edgeInclusive; // would a point on the bound be inside of the region
284 } bounds[] =
285 {
286 { diamondCenter + tcu::Vector<deInt64,2>(0, -halfPixel), diamondCenter + tcu::Vector<deInt64,2>(-halfPixel, 0), false },
287 { diamondCenter + tcu::Vector<deInt64,2>(-halfPixel, 0), diamondCenter + tcu::Vector<deInt64,2>(0, halfPixel), false },
288 { diamondCenter + tcu::Vector<deInt64,2>(0, halfPixel), diamondCenter + tcu::Vector<deInt64,2>(halfPixel, 0), true },
289 { diamondCenter + tcu::Vector<deInt64,2>(halfPixel, 0), diamondCenter + tcu::Vector<deInt64,2>(0, -halfPixel), true },
290 };
291
292 const struct DiamondCorners
293 {
294 enum CORNER_EDGE_CASE_BEHAVIOR
295 {
296 CORNER_EDGE_CASE_NONE, // if the line intersects just a corner, no entering or exiting
297 CORNER_EDGE_CASE_HIT, // if the line intersects just a corner, entering and exit
298 CORNER_EDGE_CASE_HIT_FIRST_QUARTER, // if the line intersects just a corner and the line has either endpoint in (+X,-Y) direction (preturbing moves the line inside)
299 CORNER_EDGE_CASE_HIT_SECOND_QUARTER // if the line intersects just a corner and the line has either endpoint in (+X,+Y) direction (preturbing moves the line inside)
300 };
301 enum CORNER_START_CASE_BEHAVIOR
302 {
303 CORNER_START_CASE_NONE, // the line starting point is outside, no exiting
304 CORNER_START_CASE_OUTSIDE, // exit, if line does not intersect the region (preturbing moves the start point inside)
305 CORNER_START_CASE_POSITIVE_Y_45, // exit, if line the angle of line vector and X-axis is in range (0, 45] in positive Y side.
306 CORNER_START_CASE_NEGATIVE_Y_45 // exit, if line the angle of line vector and X-axis is in range [0, 45] in negative Y side.
307 };
308 enum CORNER_END_CASE_BEHAVIOR
309 {
310 CORNER_END_CASE_NONE, // end is inside, no exiting (preturbing moves the line end inside)
311 CORNER_END_CASE_DIRECTION, // exit, if line intersected the region (preturbing moves the line end outside)
312 CORNER_END_CASE_DIRECTION_AND_FIRST_QUARTER, // exit, if line intersected the region, or line originates from (+X,-Y) direction (preturbing moves the line end outside)
313 CORNER_END_CASE_DIRECTION_AND_SECOND_QUARTER // exit, if line intersected the region, or line originates from (+X,+Y) direction (preturbing moves the line end outside)
314 };
315
316 tcu::Vector<deInt64,2> dp;
317 bool pointInclusive; // would a point in this corner intersect with the region
318 CORNER_EDGE_CASE_BEHAVIOR lineBehavior; // would a line segment going through this corner intersect with the region
319 CORNER_START_CASE_BEHAVIOR startBehavior; // how the corner behaves if the start point at the corner
320 CORNER_END_CASE_BEHAVIOR endBehavior; // how the corner behaves if the end point at the corner
321 } corners[] =
322 {
323 { tcu::Vector<deInt64,2>(0, -halfPixel), false, DiamondCorners::CORNER_EDGE_CASE_HIT_SECOND_QUARTER, DiamondCorners::CORNER_START_CASE_POSITIVE_Y_45, DiamondCorners::CORNER_END_CASE_DIRECTION_AND_SECOND_QUARTER},
324 { tcu::Vector<deInt64,2>(-halfPixel, 0), false, DiamondCorners::CORNER_EDGE_CASE_NONE, DiamondCorners::CORNER_START_CASE_NONE, DiamondCorners::CORNER_END_CASE_DIRECTION },
325 { tcu::Vector<deInt64,2>(0, halfPixel), false, DiamondCorners::CORNER_EDGE_CASE_HIT_FIRST_QUARTER, DiamondCorners::CORNER_START_CASE_NEGATIVE_Y_45, DiamondCorners::CORNER_END_CASE_DIRECTION_AND_FIRST_QUARTER },
326 { tcu::Vector<deInt64,2>(halfPixel, 0), true, DiamondCorners::CORNER_EDGE_CASE_HIT, DiamondCorners::CORNER_START_CASE_OUTSIDE, DiamondCorners::CORNER_END_CASE_NONE },
327 };
328
329 // Corner cases at the corners
330 for (int ndx = 0; ndx < DE_LENGTH_OF_ARRAY(corners); ++ndx)
331 {
332 const tcu::Vector<deInt64,2> p = diamondCenter + corners[ndx].dp;
333 const bool intersectsAtCorner = LineRasterUtil::vertexOnLineSegment(p, line);
334
335 if (!intersectsAtCorner)
336 continue;
337
338 // line segment body intersects with the corner
339 if (p != line.m_v0 && p != line.m_v1)
340 {
341 if (corners[ndx].lineBehavior == DiamondCorners::CORNER_EDGE_CASE_HIT)
342 return true;
343
344 // endpoint in (+X, -Y) (X or Y may be 0) direction <==> x*y <= 0
345 if (corners[ndx].lineBehavior == DiamondCorners::CORNER_EDGE_CASE_HIT_FIRST_QUARTER &&
346 (line.direction().x() * line.direction().y()) <= 0)
347 return true;
348
349 // endpoint in (+X, +Y) (Y > 0) direction <==> x*y > 0
350 if (corners[ndx].lineBehavior == DiamondCorners::CORNER_EDGE_CASE_HIT_SECOND_QUARTER &&
351 (line.direction().x() * line.direction().y()) > 0)
352 return true;
353 }
354
355 // line exits the area at the corner
356 if (lineInCornerAngleRange(line, corners[ndx].dp))
357 {
358 const bool startIsInside = corners[ndx].pointInclusive || p != line.m_v0;
359 const bool endIsOutside = !corners[ndx].pointInclusive || p != line.m_v1;
360
361 // starting point is inside the region and end endpoint is outside
362 if (startIsInside && endIsOutside)
363 return true;
364 }
365
366 // line end is at the corner
367 if (p == line.m_v1)
368 {
369 if (corners[ndx].endBehavior == DiamondCorners::CORNER_END_CASE_DIRECTION ||
370 corners[ndx].endBehavior == DiamondCorners::CORNER_END_CASE_DIRECTION_AND_FIRST_QUARTER ||
371 corners[ndx].endBehavior == DiamondCorners::CORNER_END_CASE_DIRECTION_AND_SECOND_QUARTER)
372 {
373 // did the line intersect the region
374 if (lineInCornerAngleRange(line, corners[ndx].dp))
375 return true;
376 }
377
378 // due to the perturbed endpoint, lines at this the angle will cause and enter-exit pair
379 if (corners[ndx].endBehavior == DiamondCorners::CORNER_END_CASE_DIRECTION_AND_FIRST_QUARTER &&
380 line.direction().x() < 0 &&
381 line.direction().y() > 0)
382 return true;
383 if (corners[ndx].endBehavior == DiamondCorners::CORNER_END_CASE_DIRECTION_AND_SECOND_QUARTER &&
384 line.direction().x() > 0 &&
385 line.direction().y() > 0)
386 return true;
387 }
388
389 // line start is at the corner
390 if (p == line.m_v0)
391 {
392 if (corners[ndx].startBehavior == DiamondCorners::CORNER_START_CASE_OUTSIDE)
393 {
394 // if the line is not going inside, it will exit
395 if (lineInCornerOutsideAngleRange(line, corners[ndx].dp))
396 return true;
397 }
398
399 // exit, if line the angle between line vector and X-axis is in range (0, 45] in positive Y side.
400 if (corners[ndx].startBehavior == DiamondCorners::CORNER_START_CASE_POSITIVE_Y_45 &&
401 line.direction().x() > 0 &&
402 line.direction().y() > 0 &&
403 line.direction().y() <= line.direction().x())
404 return true;
405
406 // exit, if line the angle between line vector and X-axis is in range [0, 45] in negative Y side.
407 if (corners[ndx].startBehavior == DiamondCorners::CORNER_START_CASE_NEGATIVE_Y_45 &&
408 line.direction().x() > 0 &&
409 line.direction().y() <= 0 &&
410 -line.direction().y() <= line.direction().x())
411 return true;
412 }
413 }
414
415 // Does the line intersect boundary at the left == exits the diamond
416 for (int ndx = 0; ndx < DE_LENGTH_OF_ARRAY(bounds); ++ndx)
417 {
418 const bool startVertexInside = LineRasterUtil::vertexOnLeftSideOfLine (line.m_v0, LineRasterUtil::SubpixelLineSegment(bounds[ndx].p0, bounds[ndx].p1)) ||
419 (bounds[ndx].edgeInclusive && LineRasterUtil::vertexOnLine (line.m_v0, LineRasterUtil::SubpixelLineSegment(bounds[ndx].p0, bounds[ndx].p1)));
420 const bool endVertexInside = LineRasterUtil::vertexOnLeftSideOfLine (line.m_v1, LineRasterUtil::SubpixelLineSegment(bounds[ndx].p0, bounds[ndx].p1)) ||
421 (bounds[ndx].edgeInclusive && LineRasterUtil::vertexOnLine (line.m_v1, LineRasterUtil::SubpixelLineSegment(bounds[ndx].p0, bounds[ndx].p1)));
422
423 // start must be on inside this half space (left or at the inclusive boundary)
424 if (!startVertexInside)
425 continue;
426
427 // end must be outside of this half-space (right or at non-inclusive boundary)
428 if (endVertexInside)
429 continue;
430
431 // Does the line via v0 and v1 intersect the line segment p0-p1
432 // <==> p0 and p1 are the different sides (LEFT, RIGHT) of the v0-v1 line.
433 // Corners are not allowed, they are checked already
434 LineRasterUtil::LINE_SIDE sideP0 = LineRasterUtil::getVertexSide(bounds[ndx].p0, line);
435 LineRasterUtil::LINE_SIDE sideP1 = LineRasterUtil::getVertexSide(bounds[ndx].p1, line);
436
437 if (sideP0 != LineRasterUtil::LINE_SIDE_INTERSECT &&
438 sideP1 != LineRasterUtil::LINE_SIDE_INTERSECT &&
439 sideP0 != sideP1)
440 return true;
441 }
442
443 return false;
444 }
445
446 } // LineRasterUtil
447
TriangleRasterizer(const tcu::IVec4 & viewport,const int numSamples,const RasterizationState & state)448 TriangleRasterizer::TriangleRasterizer (const tcu::IVec4& viewport, const int numSamples, const RasterizationState& state)
449 : m_viewport (viewport)
450 , m_numSamples (numSamples)
451 , m_winding (state.winding)
452 , m_horizontalFill (state.horizontalFill)
453 , m_verticalFill (state.verticalFill)
454 , m_face (FACETYPE_LAST)
455 {
456 }
457
458 /*--------------------------------------------------------------------*//*!
459 * \brief Initialize triangle rasterization
460 * \param v0 Screen-space coordinates (x, y, z) and 1/w for vertex 0.
461 * \param v1 Screen-space coordinates (x, y, z) and 1/w for vertex 1.
462 * \param v2 Screen-space coordinates (x, y, z) and 1/w for vertex 2.
463 *//*--------------------------------------------------------------------*/
init(const tcu::Vec4 & v0,const tcu::Vec4 & v1,const tcu::Vec4 & v2)464 void TriangleRasterizer::init (const tcu::Vec4& v0, const tcu::Vec4& v1, const tcu::Vec4& v2)
465 {
466 m_v0 = v0;
467 m_v1 = v1;
468 m_v2 = v2;
469
470 // Positions in fixed-point coordinates.
471 const deInt64 x0 = toSubpixelCoord(v0.x());
472 const deInt64 y0 = toSubpixelCoord(v0.y());
473 const deInt64 x1 = toSubpixelCoord(v1.x());
474 const deInt64 y1 = toSubpixelCoord(v1.y());
475 const deInt64 x2 = toSubpixelCoord(v2.x());
476 const deInt64 y2 = toSubpixelCoord(v2.y());
477
478 // Initialize edge functions.
479 if (m_winding == WINDING_CCW)
480 {
481 initEdgeCCW(m_edge01, m_horizontalFill, m_verticalFill, x0, y0, x1, y1);
482 initEdgeCCW(m_edge12, m_horizontalFill, m_verticalFill, x1, y1, x2, y2);
483 initEdgeCCW(m_edge20, m_horizontalFill, m_verticalFill, x2, y2, x0, y0);
484 }
485 else
486 {
487 // Reverse edges
488 initEdgeCCW(m_edge01, m_horizontalFill, m_verticalFill, x1, y1, x0, y0);
489 initEdgeCCW(m_edge12, m_horizontalFill, m_verticalFill, x2, y2, x1, y1);
490 initEdgeCCW(m_edge20, m_horizontalFill, m_verticalFill, x0, y0, x2, y2);
491 }
492
493 // Determine face.
494 const deInt64 s = evaluateEdge(m_edge01, x2, y2);
495 const bool positiveArea = (m_winding == WINDING_CCW) ? (s > 0) : (s < 0);
496 m_face = positiveArea ? FACETYPE_FRONT : FACETYPE_BACK;
497
498 if (!positiveArea)
499 {
500 // Reverse edges so that we can use CCW area tests & interpolation
501 reverseEdge(m_edge01);
502 reverseEdge(m_edge12);
503 reverseEdge(m_edge20);
504 }
505
506 // Bounding box
507 const deInt64 xMin = de::min(de::min(x0, x1), x2);
508 const deInt64 xMax = de::max(de::max(x0, x1), x2);
509 const deInt64 yMin = de::min(de::min(y0, y1), y2);
510 const deInt64 yMax = de::max(de::max(y0, y1), y2);
511
512 m_bboxMin.x() = floorSubpixelToPixelCoord (xMin, m_horizontalFill == FILL_LEFT);
513 m_bboxMin.y() = floorSubpixelToPixelCoord (yMin, m_verticalFill == FILL_BOTTOM);
514 m_bboxMax.x() = ceilSubpixelToPixelCoord (xMax, m_horizontalFill == FILL_RIGHT);
515 m_bboxMax.y() = ceilSubpixelToPixelCoord (yMax, m_verticalFill == FILL_TOP);
516
517 // Clamp to viewport
518 const int wX0 = m_viewport.x();
519 const int wY0 = m_viewport.y();
520 const int wX1 = wX0 + m_viewport.z() - 1;
521 const int wY1 = wY0 + m_viewport.w() -1;
522
523 m_bboxMin.x() = de::clamp(m_bboxMin.x(), wX0, wX1);
524 m_bboxMin.y() = de::clamp(m_bboxMin.y(), wY0, wY1);
525 m_bboxMax.x() = de::clamp(m_bboxMax.x(), wX0, wX1);
526 m_bboxMax.y() = de::clamp(m_bboxMax.y(), wY0, wY1);
527
528 m_curPos = m_bboxMin;
529 }
530
rasterizeSingleSample(FragmentPacket * const fragmentPackets,float * const depthValues,const int maxFragmentPackets,int & numPacketsRasterized)531 void TriangleRasterizer::rasterizeSingleSample (FragmentPacket* const fragmentPackets, float* const depthValues, const int maxFragmentPackets, int& numPacketsRasterized)
532 {
533 DE_ASSERT(maxFragmentPackets > 0);
534
535 const deUint64 halfPixel = 1ll << (RASTERIZER_SUBPIXEL_BITS-1);
536 int packetNdx = 0;
537
538 // For depth interpolation; given barycentrics A, B, C = (1 - A - B)
539 // we can reformulate the usual z = z0*A + z1*B + z2*C into more
540 // stable equation z = A*(z0 - z2) + B*(z1 - z2) + z2.
541 const float za = m_v0.z()-m_v2.z();
542 const float zb = m_v1.z()-m_v2.z();
543 const float zc = m_v2.z();
544
545 while (m_curPos.y() <= m_bboxMax.y() && packetNdx < maxFragmentPackets)
546 {
547 const int x0 = m_curPos.x();
548 const int y0 = m_curPos.y();
549
550 // Subpixel coords
551 const deInt64 sx0 = toSubpixelCoord(x0) + halfPixel;
552 const deInt64 sx1 = toSubpixelCoord(x0+1) + halfPixel;
553 const deInt64 sy0 = toSubpixelCoord(y0) + halfPixel;
554 const deInt64 sy1 = toSubpixelCoord(y0+1) + halfPixel;
555
556 const deInt64 sx[4] = { sx0, sx1, sx0, sx1 };
557 const deInt64 sy[4] = { sy0, sy0, sy1, sy1 };
558
559 // Viewport test
560 const bool outX1 = x0+1 == m_viewport.x()+m_viewport.z();
561 const bool outY1 = y0+1 == m_viewport.y()+m_viewport.w();
562
563 DE_ASSERT(x0 < m_viewport.x()+m_viewport.z());
564 DE_ASSERT(y0 < m_viewport.y()+m_viewport.w());
565
566 // Edge values
567 tcu::Vector<deInt64, 4> e01;
568 tcu::Vector<deInt64, 4> e12;
569 tcu::Vector<deInt64, 4> e20;
570
571 // Coverage
572 deUint64 coverage = 0;
573
574 // Evaluate edge values
575 for (int i = 0; i < 4; i++)
576 {
577 e01[i] = evaluateEdge(m_edge01, sx[i], sy[i]);
578 e12[i] = evaluateEdge(m_edge12, sx[i], sy[i]);
579 e20[i] = evaluateEdge(m_edge20, sx[i], sy[i]);
580 }
581
582 // Compute coverage mask
583 coverage = setCoverageValue(coverage, 1, 0, 0, 0, isInsideCCW(m_edge01, e01[0]) && isInsideCCW(m_edge12, e12[0]) && isInsideCCW(m_edge20, e20[0]));
584 coverage = setCoverageValue(coverage, 1, 1, 0, 0, !outX1 && isInsideCCW(m_edge01, e01[1]) && isInsideCCW(m_edge12, e12[1]) && isInsideCCW(m_edge20, e20[1]));
585 coverage = setCoverageValue(coverage, 1, 0, 1, 0, !outY1 && isInsideCCW(m_edge01, e01[2]) && isInsideCCW(m_edge12, e12[2]) && isInsideCCW(m_edge20, e20[2]));
586 coverage = setCoverageValue(coverage, 1, 1, 1, 0, !outX1 && !outY1 && isInsideCCW(m_edge01, e01[3]) && isInsideCCW(m_edge12, e12[3]) && isInsideCCW(m_edge20, e20[3]));
587
588 // Advance to next location
589 m_curPos.x() += 2;
590 if (m_curPos.x() > m_bboxMax.x())
591 {
592 m_curPos.y() += 2;
593 m_curPos.x() = m_bboxMin.x();
594 }
595
596 if (coverage == 0)
597 continue; // Discard.
598
599 // Floating-point edge values for barycentrics etc.
600 const tcu::Vec4 e01f = e01.asFloat();
601 const tcu::Vec4 e12f = e12.asFloat();
602 const tcu::Vec4 e20f = e20.asFloat();
603
604 // Compute depth values.
605 if (depthValues)
606 {
607 const tcu::Vec4 edgeSum = e01f + e12f + e20f;
608 const tcu::Vec4 z0 = e12f / edgeSum;
609 const tcu::Vec4 z1 = e20f / edgeSum;
610
611 depthValues[packetNdx*4+0] = z0[0]*za + z1[0]*zb + zc;
612 depthValues[packetNdx*4+1] = z0[1]*za + z1[1]*zb + zc;
613 depthValues[packetNdx*4+2] = z0[2]*za + z1[2]*zb + zc;
614 depthValues[packetNdx*4+3] = z0[3]*za + z1[3]*zb + zc;
615 }
616
617 // Compute barycentrics and write out fragment packet
618 {
619 FragmentPacket& packet = fragmentPackets[packetNdx];
620
621 const tcu::Vec4 b0 = e12f * m_v0.w();
622 const tcu::Vec4 b1 = e20f * m_v1.w();
623 const tcu::Vec4 b2 = e01f * m_v2.w();
624 const tcu::Vec4 bSum = b0 + b1 + b2;
625
626 packet.position = tcu::IVec2(x0, y0);
627 packet.coverage = coverage;
628 packet.barycentric[0] = b0 / bSum;
629 packet.barycentric[1] = b1 / bSum;
630 packet.barycentric[2] = 1.0f - packet.barycentric[0] - packet.barycentric[1];
631
632 packetNdx += 1;
633 }
634 }
635
636 DE_ASSERT(packetNdx <= maxFragmentPackets);
637 numPacketsRasterized = packetNdx;
638 }
639
640 // Sample positions - ordered as (x, y) list.
641
642 // \note Macros are used to eliminate function calls even in debug builds.
643 #define SAMPLE_POS_TO_SUBPIXEL_COORD(POS) \
644 (deInt64)((POS) * (1<<RASTERIZER_SUBPIXEL_BITS) + 0.5f)
645
646 #define SAMPLE_POS(X, Y) \
647 SAMPLE_POS_TO_SUBPIXEL_COORD(X), SAMPLE_POS_TO_SUBPIXEL_COORD(Y)
648
649 static const deInt64 s_samplePos2[] =
650 {
651 SAMPLE_POS(0.3f, 0.3f),
652 SAMPLE_POS(0.7f, 0.7f)
653 };
654
655 static const deInt64 s_samplePos4[] =
656 {
657 SAMPLE_POS(0.25f, 0.25f),
658 SAMPLE_POS(0.75f, 0.25f),
659 SAMPLE_POS(0.25f, 0.75f),
660 SAMPLE_POS(0.75f, 0.75f)
661 };
662 DE_STATIC_ASSERT(DE_LENGTH_OF_ARRAY(s_samplePos4) == 4*2);
663
664 static const deInt64 s_samplePos8[] =
665 {
666 SAMPLE_POS( 7.f/16.f, 9.f/16.f),
667 SAMPLE_POS( 9.f/16.f, 13.f/16.f),
668 SAMPLE_POS(11.f/16.f, 3.f/16.f),
669 SAMPLE_POS(13.f/16.f, 11.f/16.f),
670 SAMPLE_POS( 1.f/16.f, 7.f/16.f),
671 SAMPLE_POS( 5.f/16.f, 1.f/16.f),
672 SAMPLE_POS(15.f/16.f, 5.f/16.f),
673 SAMPLE_POS( 3.f/16.f, 15.f/16.f)
674 };
675 DE_STATIC_ASSERT(DE_LENGTH_OF_ARRAY(s_samplePos8) == 8*2);
676
677 static const deInt64 s_samplePos16[] =
678 {
679 SAMPLE_POS(1.f/8.f, 1.f/8.f),
680 SAMPLE_POS(3.f/8.f, 1.f/8.f),
681 SAMPLE_POS(5.f/8.f, 1.f/8.f),
682 SAMPLE_POS(7.f/8.f, 1.f/8.f),
683 SAMPLE_POS(1.f/8.f, 3.f/8.f),
684 SAMPLE_POS(3.f/8.f, 3.f/8.f),
685 SAMPLE_POS(5.f/8.f, 3.f/8.f),
686 SAMPLE_POS(7.f/8.f, 3.f/8.f),
687 SAMPLE_POS(1.f/8.f, 5.f/8.f),
688 SAMPLE_POS(3.f/8.f, 5.f/8.f),
689 SAMPLE_POS(5.f/8.f, 5.f/8.f),
690 SAMPLE_POS(7.f/8.f, 5.f/8.f),
691 SAMPLE_POS(1.f/8.f, 7.f/8.f),
692 SAMPLE_POS(3.f/8.f, 7.f/8.f),
693 SAMPLE_POS(5.f/8.f, 7.f/8.f),
694 SAMPLE_POS(7.f/8.f, 7.f/8.f)
695 };
696 DE_STATIC_ASSERT(DE_LENGTH_OF_ARRAY(s_samplePos16) == 16*2);
697
698 #undef SAMPLE_POS
699 #undef SAMPLE_POS_TO_SUBPIXEL_COORD
700
701 template<int NumSamples>
rasterizeMultiSample(FragmentPacket * const fragmentPackets,float * const depthValues,const int maxFragmentPackets,int & numPacketsRasterized)702 void TriangleRasterizer::rasterizeMultiSample (FragmentPacket* const fragmentPackets, float* const depthValues, const int maxFragmentPackets, int& numPacketsRasterized)
703 {
704 DE_ASSERT(maxFragmentPackets > 0);
705
706 const deInt64* samplePos = DE_NULL;
707 const deUint64 halfPixel = 1ll << (RASTERIZER_SUBPIXEL_BITS-1);
708 int packetNdx = 0;
709
710 // For depth interpolation, see rasterizeSingleSample
711 const float za = m_v0.z()-m_v2.z();
712 const float zb = m_v1.z()-m_v2.z();
713 const float zc = m_v2.z();
714
715 switch (NumSamples)
716 {
717 case 2: samplePos = s_samplePos2; break;
718 case 4: samplePos = s_samplePos4; break;
719 case 8: samplePos = s_samplePos8; break;
720 case 16: samplePos = s_samplePos16; break;
721 default:
722 DE_ASSERT(false);
723 }
724
725 while (m_curPos.y() <= m_bboxMax.y() && packetNdx < maxFragmentPackets)
726 {
727 const int x0 = m_curPos.x();
728 const int y0 = m_curPos.y();
729
730 // Base subpixel coords
731 const deInt64 sx0 = toSubpixelCoord(x0);
732 const deInt64 sx1 = toSubpixelCoord(x0+1);
733 const deInt64 sy0 = toSubpixelCoord(y0);
734 const deInt64 sy1 = toSubpixelCoord(y0+1);
735
736 const deInt64 sx[4] = { sx0, sx1, sx0, sx1 };
737 const deInt64 sy[4] = { sy0, sy0, sy1, sy1 };
738
739 // Viewport test
740 const bool outX1 = x0+1 == m_viewport.x()+m_viewport.z();
741 const bool outY1 = y0+1 == m_viewport.y()+m_viewport.w();
742
743 DE_ASSERT(x0 < m_viewport.x()+m_viewport.z());
744 DE_ASSERT(y0 < m_viewport.y()+m_viewport.w());
745
746 // Edge values
747 tcu::Vector<deInt64, 4> e01[NumSamples];
748 tcu::Vector<deInt64, 4> e12[NumSamples];
749 tcu::Vector<deInt64, 4> e20[NumSamples];
750
751 // Coverage
752 deUint64 coverage = 0;
753
754 // Evaluate edge values at sample positions
755 for (int sampleNdx = 0; sampleNdx < NumSamples; sampleNdx++)
756 {
757 const deInt64 ox = samplePos[sampleNdx*2 + 0];
758 const deInt64 oy = samplePos[sampleNdx*2 + 1];
759
760 for (int fragNdx = 0; fragNdx < 4; fragNdx++)
761 {
762 e01[sampleNdx][fragNdx] = evaluateEdge(m_edge01, sx[fragNdx] + ox, sy[fragNdx] + oy);
763 e12[sampleNdx][fragNdx] = evaluateEdge(m_edge12, sx[fragNdx] + ox, sy[fragNdx] + oy);
764 e20[sampleNdx][fragNdx] = evaluateEdge(m_edge20, sx[fragNdx] + ox, sy[fragNdx] + oy);
765 }
766 }
767
768 // Compute coverage mask
769 for (int sampleNdx = 0; sampleNdx < NumSamples; sampleNdx++)
770 {
771 coverage = setCoverageValue(coverage, NumSamples, 0, 0, sampleNdx, isInsideCCW(m_edge01, e01[sampleNdx][0]) && isInsideCCW(m_edge12, e12[sampleNdx][0]) && isInsideCCW(m_edge20, e20[sampleNdx][0]));
772 coverage = setCoverageValue(coverage, NumSamples, 1, 0, sampleNdx, !outX1 && isInsideCCW(m_edge01, e01[sampleNdx][1]) && isInsideCCW(m_edge12, e12[sampleNdx][1]) && isInsideCCW(m_edge20, e20[sampleNdx][1]));
773 coverage = setCoverageValue(coverage, NumSamples, 0, 1, sampleNdx, !outY1 && isInsideCCW(m_edge01, e01[sampleNdx][2]) && isInsideCCW(m_edge12, e12[sampleNdx][2]) && isInsideCCW(m_edge20, e20[sampleNdx][2]));
774 coverage = setCoverageValue(coverage, NumSamples, 1, 1, sampleNdx, !outX1 && !outY1 && isInsideCCW(m_edge01, e01[sampleNdx][3]) && isInsideCCW(m_edge12, e12[sampleNdx][3]) && isInsideCCW(m_edge20, e20[sampleNdx][3]));
775 }
776
777 // Advance to next location
778 m_curPos.x() += 2;
779 if (m_curPos.x() > m_bboxMax.x())
780 {
781 m_curPos.y() += 2;
782 m_curPos.x() = m_bboxMin.x();
783 }
784
785 if (coverage == 0)
786 continue; // Discard.
787
788 // Compute depth values.
789 if (depthValues)
790 {
791 for (int sampleNdx = 0; sampleNdx < NumSamples; sampleNdx++)
792 {
793 // Floating-point edge values at sample coordinates.
794 const tcu::Vec4& e01f = e01[sampleNdx].asFloat();
795 const tcu::Vec4& e12f = e12[sampleNdx].asFloat();
796 const tcu::Vec4& e20f = e20[sampleNdx].asFloat();
797
798 const tcu::Vec4 edgeSum = e01f + e12f + e20f;
799 const tcu::Vec4 z0 = e12f / edgeSum;
800 const tcu::Vec4 z1 = e20f / edgeSum;
801
802 depthValues[(packetNdx*4+0)*NumSamples + sampleNdx] = z0[0]*za + z1[0]*zb + zc;
803 depthValues[(packetNdx*4+1)*NumSamples + sampleNdx] = z0[1]*za + z1[1]*zb + zc;
804 depthValues[(packetNdx*4+2)*NumSamples + sampleNdx] = z0[2]*za + z1[2]*zb + zc;
805 depthValues[(packetNdx*4+3)*NumSamples + sampleNdx] = z0[3]*za + z1[3]*zb + zc;
806 }
807 }
808
809 // Compute barycentrics and write out fragment packet
810 {
811 FragmentPacket& packet = fragmentPackets[packetNdx];
812
813 // Floating-point edge values at pixel center.
814 tcu::Vec4 e01f;
815 tcu::Vec4 e12f;
816 tcu::Vec4 e20f;
817
818 for (int i = 0; i < 4; i++)
819 {
820 e01f[i] = float(evaluateEdge(m_edge01, sx[i] + halfPixel, sy[i] + halfPixel));
821 e12f[i] = float(evaluateEdge(m_edge12, sx[i] + halfPixel, sy[i] + halfPixel));
822 e20f[i] = float(evaluateEdge(m_edge20, sx[i] + halfPixel, sy[i] + halfPixel));
823 }
824
825 // Barycentrics & scale.
826 const tcu::Vec4 b0 = e12f * m_v0.w();
827 const tcu::Vec4 b1 = e20f * m_v1.w();
828 const tcu::Vec4 b2 = e01f * m_v2.w();
829 const tcu::Vec4 bSum = b0 + b1 + b2;
830
831 packet.position = tcu::IVec2(x0, y0);
832 packet.coverage = coverage;
833 packet.barycentric[0] = b0 / bSum;
834 packet.barycentric[1] = b1 / bSum;
835 packet.barycentric[2] = 1.0f - packet.barycentric[0] - packet.barycentric[1];
836
837 packetNdx += 1;
838 }
839 }
840
841 DE_ASSERT(packetNdx <= maxFragmentPackets);
842 numPacketsRasterized = packetNdx;
843 }
844
rasterize(FragmentPacket * const fragmentPackets,float * const depthValues,const int maxFragmentPackets,int & numPacketsRasterized)845 void TriangleRasterizer::rasterize (FragmentPacket* const fragmentPackets, float* const depthValues, const int maxFragmentPackets, int& numPacketsRasterized)
846 {
847 DE_ASSERT(maxFragmentPackets > 0);
848
849 switch (m_numSamples)
850 {
851 case 1: rasterizeSingleSample (fragmentPackets, depthValues, maxFragmentPackets, numPacketsRasterized); break;
852 case 2: rasterizeMultiSample<2> (fragmentPackets, depthValues, maxFragmentPackets, numPacketsRasterized); break;
853 case 4: rasterizeMultiSample<4> (fragmentPackets, depthValues, maxFragmentPackets, numPacketsRasterized); break;
854 case 8: rasterizeMultiSample<8> (fragmentPackets, depthValues, maxFragmentPackets, numPacketsRasterized); break;
855 case 16: rasterizeMultiSample<16> (fragmentPackets, depthValues, maxFragmentPackets, numPacketsRasterized); break;
856 default:
857 DE_ASSERT(DE_FALSE);
858 }
859 }
860
SingleSampleLineRasterizer(const tcu::IVec4 & viewport)861 SingleSampleLineRasterizer::SingleSampleLineRasterizer (const tcu::IVec4& viewport)
862 : m_viewport (viewport)
863 , m_curRowFragment (0)
864 , m_lineWidth (0.0f)
865 {
866 }
867
~SingleSampleLineRasterizer(void)868 SingleSampleLineRasterizer::~SingleSampleLineRasterizer (void)
869 {
870 }
871
init(const tcu::Vec4 & v0,const tcu::Vec4 & v1,float lineWidth)872 void SingleSampleLineRasterizer::init (const tcu::Vec4& v0, const tcu::Vec4& v1, float lineWidth)
873 {
874 const bool isXMajor = de::abs((v1 - v0).x()) >= de::abs((v1 - v0).y());
875
876 // Bounding box \note: with wide lines, the line is actually moved as in the spec
877 const deInt32 lineWidthPixels = (lineWidth > 1.0f) ? (deInt32)floor(lineWidth + 0.5f) : 1;
878
879 const tcu::Vector<deInt64,2> widthOffset = (isXMajor ? tcu::Vector<deInt64,2>(0, -1) : tcu::Vector<deInt64,2>(-1, 0)) * (toSubpixelCoord(lineWidthPixels - 1) / 2);
880
881 const deInt64 x0 = toSubpixelCoord(v0.x()) + widthOffset.x();
882 const deInt64 y0 = toSubpixelCoord(v0.y()) + widthOffset.y();
883 const deInt64 x1 = toSubpixelCoord(v1.x()) + widthOffset.x();
884 const deInt64 y1 = toSubpixelCoord(v1.y()) + widthOffset.y();
885
886 // line endpoints might be perturbed, add some margin
887 const deInt64 xMin = de::min(x0, x1) - toSubpixelCoord(1);
888 const deInt64 xMax = de::max(x0, x1) + toSubpixelCoord(1);
889 const deInt64 yMin = de::min(y0, y1) - toSubpixelCoord(1);
890 const deInt64 yMax = de::max(y0, y1) + toSubpixelCoord(1);
891
892 // Remove invisible area
893
894 if (isXMajor)
895 {
896 // clamp to viewport in major direction
897 m_bboxMin.x() = de::clamp(floorSubpixelToPixelCoord(xMin, true), m_viewport.x(), m_viewport.x() + m_viewport.z() - 1);
898 m_bboxMax.x() = de::clamp(ceilSubpixelToPixelCoord (xMax, true), m_viewport.x(), m_viewport.x() + m_viewport.z() - 1);
899
900 // clamp to padded viewport in minor direction (wide lines might bleed over viewport in minor direction)
901 m_bboxMin.y() = de::clamp(floorSubpixelToPixelCoord(yMin, true), m_viewport.y() - lineWidthPixels, m_viewport.y() + m_viewport.w() - 1);
902 m_bboxMax.y() = de::clamp(ceilSubpixelToPixelCoord (yMax, true), m_viewport.y() - lineWidthPixels, m_viewport.y() + m_viewport.w() - 1);
903 }
904 else
905 {
906 // clamp to viewport in major direction
907 m_bboxMin.y() = de::clamp(floorSubpixelToPixelCoord(yMin, true), m_viewport.y(), m_viewport.y() + m_viewport.w() - 1);
908 m_bboxMax.y() = de::clamp(ceilSubpixelToPixelCoord (yMax, true), m_viewport.y(), m_viewport.y() + m_viewport.w() - 1);
909
910 // clamp to padded viewport in minor direction (wide lines might bleed over viewport in minor direction)
911 m_bboxMin.x() = de::clamp(floorSubpixelToPixelCoord(xMin, true), m_viewport.x() - lineWidthPixels, m_viewport.x() + m_viewport.z() - 1);
912 m_bboxMax.x() = de::clamp(ceilSubpixelToPixelCoord (xMax, true), m_viewport.x() - lineWidthPixels, m_viewport.x() + m_viewport.z() - 1);
913 }
914
915 m_lineWidth = lineWidth;
916
917 m_v0 = v0;
918 m_v1 = v1;
919
920 m_curPos = m_bboxMin;
921 m_curRowFragment = 0;
922 }
923
rasterize(FragmentPacket * const fragmentPackets,float * const depthValues,const int maxFragmentPackets,int & numPacketsRasterized)924 void SingleSampleLineRasterizer::rasterize (FragmentPacket* const fragmentPackets, float* const depthValues, const int maxFragmentPackets, int& numPacketsRasterized)
925 {
926 DE_ASSERT(maxFragmentPackets > 0);
927
928 const deInt64 halfPixel = 1ll << (RASTERIZER_SUBPIXEL_BITS-1);
929 const deInt32 lineWidth = (m_lineWidth > 1.0f) ? deFloorFloatToInt32(m_lineWidth + 0.5f) : 1;
930 const bool isXMajor = de::abs((m_v1 - m_v0).x()) >= de::abs((m_v1 - m_v0).y());
931 const tcu::IVec2 minorDirection = (isXMajor) ? (tcu::IVec2(0, 1)) : (tcu::IVec2(1, 0));
932 const int minViewportLimit = (isXMajor) ? (m_viewport.y()) : (m_viewport.x());
933 const int maxViewportLimit = (isXMajor) ? (m_viewport.y() + m_viewport.w()) : (m_viewport.x() + m_viewport.z());
934 const tcu::Vector<deInt64,2> widthOffset = -minorDirection.cast<deInt64>() * (toSubpixelCoord(lineWidth - 1) / 2);
935 const tcu::Vector<deInt64,2> pa = LineRasterUtil::toSubpixelVector(m_v0.xy()) + widthOffset;
936 const tcu::Vector<deInt64,2> pb = LineRasterUtil::toSubpixelVector(m_v1.xy()) + widthOffset;
937 const LineRasterUtil::SubpixelLineSegment line = LineRasterUtil::SubpixelLineSegment(pa, pb);
938
939 int packetNdx = 0;
940
941 while (m_curPos.y() <= m_bboxMax.y() && packetNdx < maxFragmentPackets)
942 {
943 const tcu::Vector<deInt64,2> diamondPosition = LineRasterUtil::toSubpixelVector(m_curPos) + tcu::Vector<deInt64,2>(halfPixel,halfPixel);
944
945 // Should current fragment be drawn? == does the segment exit this diamond?
946 if (LineRasterUtil::doesLineSegmentExitDiamond(line, diamondPosition))
947 {
948 const tcu::Vector<deInt64,2> pr = diamondPosition;
949 const float t = tcu::dot((pr - pa).asFloat(), (pb - pa).asFloat()) / tcu::lengthSquared(pb.asFloat() - pa.asFloat());
950
951 // Rasterize on only fragments that are would end up in the viewport (i.e. visible)
952 const int fragmentLocation = (isXMajor) ? (m_curPos.y()) : (m_curPos.x());
953 const int rowFragBegin = de::max(0, minViewportLimit - fragmentLocation);
954 const int rowFragEnd = de::min(maxViewportLimit - fragmentLocation, lineWidth);
955
956 // Wide lines require multiple fragments.
957 for (; rowFragBegin + m_curRowFragment < rowFragEnd; m_curRowFragment++)
958 {
959 const int replicationId = rowFragBegin + m_curRowFragment;
960 const tcu::IVec2 fragmentPos = m_curPos + minorDirection * replicationId;
961
962 // We only rasterize visible area
963 DE_ASSERT(LineRasterUtil::inViewport(fragmentPos, m_viewport));
964
965 // Compute depth values.
966 if (depthValues)
967 {
968 const float za = m_v0.z();
969 const float zb = m_v1.z();
970
971 depthValues[packetNdx*4+0] = (1 - t) * za + t * zb;
972 depthValues[packetNdx*4+1] = 0;
973 depthValues[packetNdx*4+2] = 0;
974 depthValues[packetNdx*4+3] = 0;
975 }
976
977 {
978 // output this fragment
979 // \note In order to make consistent output with multisampled line rasterization, output "barycentric" coordinates
980 FragmentPacket& packet = fragmentPackets[packetNdx];
981
982 const tcu::Vec4 b0 = tcu::Vec4(1 - t);
983 const tcu::Vec4 b1 = tcu::Vec4(t);
984 const tcu::Vec4 ooSum = 1.0f / (b0 + b1);
985
986 packet.position = fragmentPos;
987 packet.coverage = getCoverageBit(1, 0, 0, 0);
988 packet.barycentric[0] = b0 * ooSum;
989 packet.barycentric[1] = b1 * ooSum;
990 packet.barycentric[2] = tcu::Vec4(0.0f);
991
992 packetNdx += 1;
993 }
994
995 if (packetNdx == maxFragmentPackets)
996 {
997 m_curRowFragment++; // don't redraw this fragment again next time
998 numPacketsRasterized = packetNdx;
999 return;
1000 }
1001 }
1002
1003 m_curRowFragment = 0;
1004 }
1005
1006 ++m_curPos.x();
1007 if (m_curPos.x() > m_bboxMax.x())
1008 {
1009 ++m_curPos.y();
1010 m_curPos.x() = m_bboxMin.x();
1011 }
1012 }
1013
1014 DE_ASSERT(packetNdx <= maxFragmentPackets);
1015 numPacketsRasterized = packetNdx;
1016 }
1017
MultiSampleLineRasterizer(const int numSamples,const tcu::IVec4 & viewport)1018 MultiSampleLineRasterizer::MultiSampleLineRasterizer (const int numSamples, const tcu::IVec4& viewport)
1019 : m_numSamples (numSamples)
1020 , m_triangleRasterizer0 (viewport, m_numSamples, RasterizationState())
1021 , m_triangleRasterizer1 (viewport, m_numSamples, RasterizationState())
1022 {
1023 }
1024
~MultiSampleLineRasterizer()1025 MultiSampleLineRasterizer::~MultiSampleLineRasterizer ()
1026 {
1027 }
1028
init(const tcu::Vec4 & v0,const tcu::Vec4 & v1,float lineWidth)1029 void MultiSampleLineRasterizer::init (const tcu::Vec4& v0, const tcu::Vec4& v1, float lineWidth)
1030 {
1031 // allow creation of single sampled rasterizer objects but do not allow using them
1032 DE_ASSERT(m_numSamples > 1);
1033
1034 const tcu::Vec2 lineVec = tcu::Vec2(tcu::Vec4(v1).xy()) - tcu::Vec2(tcu::Vec4(v0).xy());
1035 const tcu::Vec2 normal2 = tcu::normalize(tcu::Vec2(-lineVec[1], lineVec[0]));
1036 const tcu::Vec4 normal4 = tcu::Vec4(normal2.x(), normal2.y(), 0, 0);
1037 const float offset = lineWidth / 2.0f;
1038
1039 const tcu::Vec4 p0 = v0 + normal4 * offset;
1040 const tcu::Vec4 p1 = v0 - normal4 * offset;
1041 const tcu::Vec4 p2 = v1 - normal4 * offset;
1042 const tcu::Vec4 p3 = v1 + normal4 * offset;
1043
1044 // Edge 0 -> 1 is always along the line and edge 1 -> 2 is in 90 degree angle to the line
1045 m_triangleRasterizer0.init(p0, p3, p2);
1046 m_triangleRasterizer1.init(p2, p1, p0);
1047 }
1048
rasterize(FragmentPacket * const fragmentPackets,float * const depthValues,const int maxFragmentPackets,int & numPacketsRasterized)1049 void MultiSampleLineRasterizer::rasterize (FragmentPacket* const fragmentPackets, float* const depthValues, const int maxFragmentPackets, int& numPacketsRasterized)
1050 {
1051 DE_ASSERT(maxFragmentPackets > 0);
1052
1053 m_triangleRasterizer0.rasterize(fragmentPackets, depthValues, maxFragmentPackets, numPacketsRasterized);
1054
1055 // Remove 3rd barycentric value and rebalance. Lines do not have non-zero barycentric at index 2
1056 for (int packNdx = 0; packNdx < numPacketsRasterized; ++packNdx)
1057 for (int fragNdx = 0; fragNdx < 4; fragNdx++)
1058 {
1059 float removedValue = fragmentPackets[packNdx].barycentric[2][fragNdx];
1060 fragmentPackets[packNdx].barycentric[2][fragNdx] = 0.0f;
1061 fragmentPackets[packNdx].barycentric[1][fragNdx] += removedValue;
1062 }
1063
1064 // rasterizer 0 filled the whole buffer?
1065 if (numPacketsRasterized == maxFragmentPackets)
1066 return;
1067
1068 {
1069 FragmentPacket* const nextFragmentPackets = fragmentPackets + numPacketsRasterized;
1070 float* nextDepthValues = (depthValues) ? (depthValues+4*numPacketsRasterized*m_numSamples) : (DE_NULL);
1071 int numPacketsRasterized2 = 0;
1072
1073 m_triangleRasterizer1.rasterize(nextFragmentPackets, nextDepthValues, maxFragmentPackets - numPacketsRasterized, numPacketsRasterized2);
1074
1075 numPacketsRasterized += numPacketsRasterized2;
1076
1077 // Fix swapped barycentrics in the second triangle
1078 for (int packNdx = 0; packNdx < numPacketsRasterized2; ++packNdx)
1079 for (int fragNdx = 0; fragNdx < 4; fragNdx++)
1080 {
1081 float removedValue = nextFragmentPackets[packNdx].barycentric[2][fragNdx];
1082 nextFragmentPackets[packNdx].barycentric[2][fragNdx] = 0.0f;
1083 nextFragmentPackets[packNdx].barycentric[1][fragNdx] += removedValue;
1084
1085 // edge has reversed direction
1086 std::swap(nextFragmentPackets[packNdx].barycentric[0][fragNdx], nextFragmentPackets[packNdx].barycentric[1][fragNdx]);
1087 }
1088 }
1089 }
1090
LineExitDiamondGenerator(void)1091 LineExitDiamondGenerator::LineExitDiamondGenerator (void)
1092 {
1093 }
1094
~LineExitDiamondGenerator(void)1095 LineExitDiamondGenerator::~LineExitDiamondGenerator (void)
1096 {
1097 }
1098
init(const tcu::Vec4 & v0,const tcu::Vec4 & v1)1099 void LineExitDiamondGenerator::init (const tcu::Vec4& v0, const tcu::Vec4& v1)
1100 {
1101 const deInt64 x0 = toSubpixelCoord(v0.x());
1102 const deInt64 y0 = toSubpixelCoord(v0.y());
1103 const deInt64 x1 = toSubpixelCoord(v1.x());
1104 const deInt64 y1 = toSubpixelCoord(v1.y());
1105
1106 // line endpoints might be perturbed, add some margin
1107 const deInt64 xMin = de::min(x0, x1) - toSubpixelCoord(1);
1108 const deInt64 xMax = de::max(x0, x1) + toSubpixelCoord(1);
1109 const deInt64 yMin = de::min(y0, y1) - toSubpixelCoord(1);
1110 const deInt64 yMax = de::max(y0, y1) + toSubpixelCoord(1);
1111
1112 m_bboxMin.x() = floorSubpixelToPixelCoord(xMin, true);
1113 m_bboxMin.y() = floorSubpixelToPixelCoord(yMin, true);
1114 m_bboxMax.x() = ceilSubpixelToPixelCoord (xMax, true);
1115 m_bboxMax.y() = ceilSubpixelToPixelCoord (yMax, true);
1116
1117 m_v0 = v0;
1118 m_v1 = v1;
1119
1120 m_curPos = m_bboxMin;
1121 }
1122
rasterize(LineExitDiamond * const lineDiamonds,const int maxDiamonds,int & numWritten)1123 void LineExitDiamondGenerator::rasterize (LineExitDiamond* const lineDiamonds, const int maxDiamonds, int& numWritten)
1124 {
1125 DE_ASSERT(maxDiamonds > 0);
1126
1127 const deInt64 halfPixel = 1ll << (RASTERIZER_SUBPIXEL_BITS-1);
1128 const tcu::Vector<deInt64,2> pa = LineRasterUtil::toSubpixelVector(m_v0.xy());
1129 const tcu::Vector<deInt64,2> pb = LineRasterUtil::toSubpixelVector(m_v1.xy());
1130 const LineRasterUtil::SubpixelLineSegment line = LineRasterUtil::SubpixelLineSegment(pa, pb);
1131
1132 int diamondNdx = 0;
1133
1134 while (m_curPos.y() <= m_bboxMax.y() && diamondNdx < maxDiamonds)
1135 {
1136 const tcu::Vector<deInt64,2> diamondPosition = LineRasterUtil::toSubpixelVector(m_curPos) + tcu::Vector<deInt64,2>(halfPixel,halfPixel);
1137
1138 if (LineRasterUtil::doesLineSegmentExitDiamond(line, diamondPosition))
1139 {
1140 LineExitDiamond& packet = lineDiamonds[diamondNdx];
1141 packet.position = m_curPos;
1142 ++diamondNdx;
1143 }
1144
1145 ++m_curPos.x();
1146 if (m_curPos.x() > m_bboxMax.x())
1147 {
1148 ++m_curPos.y();
1149 m_curPos.x() = m_bboxMin.x();
1150 }
1151 }
1152
1153 DE_ASSERT(diamondNdx <= maxDiamonds);
1154 numWritten = diamondNdx;
1155 }
1156
1157 } // rr
1158