Mirrors/overte
3
0
Fork 0
mirror of https://github.com/overte-org/overte.git synced 2025-04-23 14:14:07 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

faster TextureUsage::process2DImageColor()

Browse source
This commit is contained in:
Andrew Meadows 2016-08-05 23:38:45 -07:00
parent 652bea8cd0
commit 4f2c00af46
1 changed files with 11 additions and 13 deletions

24
libraries/model/src/model/TextureMap.cpp
View file

@ -59,29 +59,27 @@ const QImage TextureUsage::process2DImageColor(const QImage& srcImage, bool& val
const uint8 OPAQUE_ALPHA = 255;
const uint8 TRANSPARENT_ALPHA = 0;
if (image.hasAlphaChannel()) {
std::map<uint8, uint32> alphaHistogram;
if (image.format() != QImage::Format_ARGB32) {
image = image.convertToFormat(QImage::Format_ARGB32);
}
// Actual alpha channel? create the histogram
for (int y = 0; y < image.height(); ++y) {
// Count the opaque and transparent pixels
int numOpaques = 0;
int numTransparents = 0;
int height = image.height();
int width = image.width();
for (int y = 0; y < height; ++y) {
const QRgb* data = reinterpret_cast<const QRgb*>(image.constScanLine(y));
for (int x = 0; x < image.width(); ++x) {
for (int x = 0; x < width; ++x) {
auto alpha = qAlpha(data[x]);
alphaHistogram[alpha] ++;
validAlpha = validAlpha || (alpha != OPAQUE_ALPHA);
numOpaques += (int)(alpha == OPAQUE_ALPHA);
numTransparents += (int)(alpha == TRANSPARENT_ALPHA);
}
}
// If alpha was meaningfull refine
if (validAlpha && (alphaHistogram.size() > 1)) {
auto totalNumPixels = image.height() * image.width();
auto numOpaques = alphaHistogram[OPAQUE_ALPHA];
auto numTransparents = alphaHistogram[TRANSPARENT_ALPHA];
auto totalNumPixels = height * width;
if (numOpaques != totalNumPixels) {
auto numTranslucents = totalNumPixels - numOpaques - numTransparents;
alphaAsMask = ((numTranslucents / (double)totalNumPixels) < 0.05);
}
}