| /* |
| * Copyright 2013 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "src/gpu/RectanizerSkyline.h" |
| |
| #include "include/private/base/SkAssert.h" |
| #include "src/core/SkIPoint16.h" |
| |
| #include <algorithm> |
| |
| namespace skgpu { |
| |
| bool RectanizerSkyline::addRect(int width, int height, SkIPoint16* loc) { |
| if ((unsigned)width > (unsigned)this->width() || |
| (unsigned)height > (unsigned)this->height()) { |
| return false; |
| } |
| |
| // find position for new rectangle |
| int bestWidth = this->width() + 1; |
| int bestX = 0; |
| int bestY = this->height() + 1; |
| int bestIndex = -1; |
| for (int i = 0; i < fSkyline.size(); ++i) { |
| int y; |
| if (this->rectangleFits(i, width, height, &y)) { |
| // minimize y position first, then width of skyline |
| if (y < bestY || (y == bestY && fSkyline[i].fWidth < bestWidth)) { |
| bestIndex = i; |
| bestWidth = fSkyline[i].fWidth; |
| bestX = fSkyline[i].fX; |
| bestY = y; |
| } |
| } |
| } |
| |
| // add rectangle to skyline |
| if (-1 != bestIndex) { |
| this->addSkylineLevel(bestIndex, bestX, bestY, width, height); |
| loc->fX = bestX; |
| loc->fY = bestY; |
| |
| fAreaSoFar += width*height; |
| return true; |
| } |
| |
| loc->fX = 0; |
| loc->fY = 0; |
| return false; |
| } |
| |
| bool RectanizerSkyline::rectangleFits(int skylineIndex, int width, int height, int* ypos) const { |
| int x = fSkyline[skylineIndex].fX; |
| if (x + width > this->width()) { |
| return false; |
| } |
| |
| int widthLeft = width; |
| int i = skylineIndex; |
| int y = fSkyline[skylineIndex].fY; |
| while (widthLeft > 0) { |
| y = std::max(y, fSkyline[i].fY); |
| if (y + height > this->height()) { |
| return false; |
| } |
| widthLeft -= fSkyline[i].fWidth; |
| ++i; |
| SkASSERT(i < fSkyline.size() || widthLeft <= 0); |
| } |
| |
| *ypos = y; |
| return true; |
| } |
| |
| void RectanizerSkyline::addSkylineLevel(int skylineIndex, int x, int y, int width, int height) { |
| SkylineSegment newSegment; |
| newSegment.fX = x; |
| newSegment.fY = y + height; |
| newSegment.fWidth = width; |
| fSkyline.insert(skylineIndex, 1, &newSegment); |
| |
| SkASSERT(newSegment.fX + newSegment.fWidth <= this->width()); |
| SkASSERT(newSegment.fY <= this->height()); |
| |
| // delete width of the new skyline segment from following ones |
| for (int i = skylineIndex+1; i < fSkyline.size(); ++i) { |
| // The new segment subsumes all or part of fSkyline[i] |
| SkASSERT(fSkyline[i-1].fX <= fSkyline[i].fX); |
| |
| if (fSkyline[i].fX < fSkyline[i-1].fX + fSkyline[i-1].fWidth) { |
| int shrink = fSkyline[i-1].fX + fSkyline[i-1].fWidth - fSkyline[i].fX; |
| |
| fSkyline[i].fX += shrink; |
| fSkyline[i].fWidth -= shrink; |
| |
| if (fSkyline[i].fWidth <= 0) { |
| // fully consumed |
| fSkyline.remove(i); |
| --i; |
| } else { |
| // only partially consumed |
| break; |
| } |
| } else { |
| break; |
| } |
| } |
| |
| // merge fSkylines |
| for (int i = 0; i < fSkyline.size()-1; ++i) { |
| if (fSkyline[i].fY == fSkyline[i+1].fY) { |
| fSkyline[i].fWidth += fSkyline[i+1].fWidth; |
| fSkyline.remove(i+1); |
| --i; |
| } |
| } |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| Rectanizer* Rectanizer::Factory(int width, int height) { |
| return new RectanizerSkyline(width, height); |
| } |
| |
| } // End of namespace skgpu |