skia2/debugger/SkHitBox.cpp
chudy@google.com e606d6e210 SkHitBox added.
SkHitBox is a class that determines which draw command is associated with the pixel located at x,y. By calculating a single point instead of the entire bitmap at once there is no visible performance slowdown.

Review URL: https://codereview.appspot.com/6350098

git-svn-id: http://skia.googlecode.com/svn/trunk@4565 2bbb7eff-a529-9590-31e7-b0007b416f81
2012-07-12 14:31:25 +00:00

67 lines
1.9 KiB
C++

/*
* Copyright 2012 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkHitBox.h"
SkHitBox::SkHitBox() {
fHitBox = NULL;
fX = -1;
fY = -1;
fLayer = -1;
}
SkHitBox::~SkHitBox() {}
void SkHitBox::alloc(int width, int height) {
free(fHitBox);
int length = width * height;
fHitBox = (int*) malloc(length * sizeof(int));
for (int i = 0; i < length; i++) {
fHitBox[i] = 0;
}
}
void SkHitBox::updateHitBox(SkBitmap* newBitmap, int layer) {
int length = fPrev.width() * fPrev.height();
int* prevBase = (int*)fPrev.getPixels();
int* currBase = (int*)newBitmap->getPixels();
for (int i = 0; i < length; i++) {
if (SkUnPreMultiply::PMColorToColor(prevBase[i]) !=
SkUnPreMultiply::PMColorToColor(currBase[i])) {
fHitBox[i] = layer;
}
}
if (fPrev.empty()) {
alloc(newBitmap->width(), newBitmap->height());
fPrev.setConfig(SkBitmap::kARGB_8888_Config, newBitmap->width(), newBitmap->height());
fPrev.allocPixels();
}
newBitmap->deepCopyTo(&fPrev, SkBitmap::kARGB_8888_Config);
}
void SkHitBox::updateHitPoint(SkBitmap* newBitmap, int layer) {
int* prevBase = (int*)fPrev.getPixels();
int* currBase = (int*)newBitmap->getPixels();
int pixel = fY * fPrev.width() + fX;
if (pointIsSet() && !fPrev.empty()) {
if (SkUnPreMultiply::PMColorToColor(prevBase[pixel]) !=
SkUnPreMultiply::PMColorToColor(currBase[pixel])) {
fLayer = layer;
}
}
if (fPrev.empty()) {
alloc(newBitmap->width(), newBitmap->height());
fPrev.setConfig(SkBitmap::kARGB_8888_Config, newBitmap->width(), newBitmap->height());
fPrev.allocPixels();
}
newBitmap->deepCopyTo(&fPrev, SkBitmap::kARGB_8888_Config);
}