float Detector::sizeOfBlackWhiteBlackRunBothWays(int fromX, int fromY, int toX, int toY) {
float result = sizeOfBlackWhiteBlackRun(fromX, fromY, toX, toY);
// Now count other way -- don't run off image though of course
float scale = 1.0f;
int otherToX = fromX - (toX - fromX);
if (otherToX < 0) {
scale = (float) fromX / (float) (fromX - otherToX);
otherToX = 0;
} else if (otherToX >= (int)image_->getWidth()) {
scale = (float) (image_->getWidth() - 1 - fromX) / (float) (otherToX - fromX);
otherToX = image_->getWidth() - 1;
}
int otherToY = (int) (fromY - (toY - fromY) * scale);
scale = 1.0f;
if (otherToY < 0) {
scale = (float) fromY / (float) (fromY - otherToY);
otherToY = 0;
} else if (otherToY >= (int)image_->getHeight()) {
scale = (float) (image_->getHeight() - 1 - fromY) / (float) (otherToY - fromY);
otherToY = image_->getHeight() - 1;
}
otherToX = (int) (fromX + (otherToX - fromX) * scale);
result += sizeOfBlackWhiteBlackRun(fromX, fromY, otherToX, otherToY);
// Middle pixel is double-counted this way; subtract 1
return result - 1.0f;
}
float Detector::sizeOfBlackWhiteBlackRunBothWays(int fromX, int fromY,
int toX, int toY) {
float result = sizeOfBlackWhiteBlackRun(fromX, fromY, toX, toY);
// Now count other way -- don't run off image though of course
size_t otherToX = fromX - (toX - fromX);
if (otherToX >= image_->getWidth()) {
otherToX = image_->getWidth();
}
size_t otherToY = fromY - (toY - fromY);
if (otherToY >= image_->getHeight()) {
otherToY = image_->getHeight();
}
result += sizeOfBlackWhiteBlackRun(fromX, fromY, otherToX, otherToY);
return result - 1.0f; // -1 because we counted the middle pixel twice
}
