// This method does some trickery type stuff where we perform the TestPackingImages method over and over,
// trying to reduce the image size until we have found the smallest possible image we can fit.
private bool PackImageRectangles()
{
// create a dictionary for our test image placements
Dictionary <string, Rectangle> testImagePlacement = new Dictionary <string, Rectangle>();
// get the size of our smallest image
int smallestWidth = int.MaxValue;
int smallestHeight = int.MaxValue;
foreach (var size in imageSizes)
{
smallestWidth = Math.Min(smallestWidth, size.Value.Width);
smallestHeight = Math.Min(smallestHeight, size.Value.Height);
}
// we need a couple values for testing
int testWidth = outputWidth;
int testHeight = outputHeight;
bool shrinkVertical = false;
// just keep looping...
while (true)
{
// make sure our test dictionary is empty
testImagePlacement.Clear();
// try to pack the images into our current test size
if (!TestPackingImages(testWidth, testHeight, testImagePlacement))
{
// if that failed...
// if we have no images in imagePlacement, i.e. we've never succeeded at PackImages,
// show an error and return false since there is no way to fit the images into our
// maximum size texture
if (imagePlacement.Count == 0)
{
return(false);
}
// otherwise return true to use our last good results
if (shrinkVertical)
{
return(true);
}
shrinkVertical = true;
testWidth += smallestWidth + padding + padding;
testHeight += smallestHeight + padding + padding;
continue;
}
// clear the imagePlacement dictionary and add our test results in
imagePlacement.Clear();
foreach (var pair in testImagePlacement)
{
imagePlacement.Add(pair.Key, pair.Value);
}
// figure out the smallest bitmap that will hold all the images
testWidth = testHeight = 0;
foreach (var pair in imagePlacement)
{
testWidth = Math.Max(testWidth, pair.Value.Right);
testHeight = Math.Max(testHeight, pair.Value.Bottom);
}
// subtract the extra padding on the right and bottom
if (!shrinkVertical)
{
testWidth -= padding;
}
testHeight -= padding;
// if we require a power of two texture, find the next power of two that can fit this image
if (requirePow2)
{
testWidth = MiscHelper.FindNextPowerOfTwo(testWidth);
testHeight = MiscHelper.FindNextPowerOfTwo(testHeight);
}
// if we require a square texture, set the width and height to the larger of the two
if (requireSquare)
{
int max = Math.Max(testWidth, testHeight);
testWidth = testHeight = max;
}
// if the test results are the same as our last output results, we've reached an optimal size,
// so we can just be done
if (testWidth == outputWidth && testHeight == outputHeight)
{
if (shrinkVertical)
{
return(true);
}
shrinkVertical = true;
}
// save the test results as our last known good results
outputWidth = testWidth;
outputHeight = testHeight;
// subtract the smallest image size out for the next test iteration
if (!shrinkVertical)
{
testWidth -= smallestWidth;
}
testHeight -= smallestHeight;
}
}
