ofxMsdfgen/src/ofxMsdfgen.cpp

80 lines
4.3 KiB
C++

#include "ofxMsdfgen.h"
#include "BitmapRef.hpp"
#include "ofGraphicsConstants.h"
#include "ofPixels.h"
bool ofxMsdfgen::generateAtlas(const char * fontFilename){
bool success = false;
// Initialize instance of FreeType library
if(msdfgen::FreetypeHandle * ft = msdfgen::initializeFreetype()){
// Load font file
if(msdfgen::FontHandle * font = msdfgen::loadFont(ft, fontFilename)){
// Storage for glyph geometry and their coordinates in the atlas
std::vector <msdf_atlas::GlyphGeometry> glyphs;
// FontGeometry is a helper class that loads a set of glyphs from a single font.
// It can also be used to get additional font metrics, kerning information, etc.
msdf_atlas::FontGeometry fontGeometry(&glyphs);
// Load a set of character glyphs:
// The second argument can be ignored unless you mix different font sizes in one atlas.
// In the last argument, you can specify a charset other than ASCII.
// To load specific glyph indices, use loadGlyphs instead.
fontGeometry.loadCharset(font, 1.0, msdf_atlas::Charset::ASCII);
// Apply MSDF edge coloring. See edge-coloring.h for other coloring strategies.
const double maxCornerAngle = 3.0;
for(msdf_atlas::GlyphGeometry & glyph : glyphs){
glyph.edgeColoring(&msdfgen::edgeColoringInkTrap, maxCornerAngle, 0);
}
// TightAtlasPacker class computes the layout of the atlas.
msdf_atlas::TightAtlasPacker packer;
// Set atlas parameters:
// setDimensions or setDimensionsConstraint to find the best value
packer.setDimensionsConstraint(msdf_atlas::TightAtlasPacker::DimensionsConstraint::SQUARE);
// setScale for a fixed size or setMinimumScale to use the largest that fits
packer.setMinimumScale(24.0);
// setPixelRange or setUnitRange
packer.setPixelRange(2.0);
packer.setMiterLimit(1.0);
// Compute atlas layout - pack glyphs
packer.pack(glyphs.data(), glyphs.size());
// Get final atlas dimensions
int width = 0, height = 0;
packer.getDimensions(width, height);
// The ImmediateAtlasGenerator class facilitates the generation of the atlas bitmap.
msdf_atlas::ImmediateAtlasGenerator <
float, // pixel type of buffer for individual glyphs depends on generator function
3, // number of atlas color channels
& msdf_atlas::msdfGenerator, // function to generate bitmaps for individual glyphs
msdf_atlas::BitmapAtlasStorage <float, 3> // class that stores the atlas bitmap
// For example, a custom atlas storage class that stores it in VRAM can be used.
> generator(width, height);
// GeneratorAttributes can be modified to change the generator's default settings.
msdf_atlas::GeneratorAttributes attributes;
generator.setAttributes(attributes);
generator.setThreadCount(12);
// Generate atlas bitmap
generator.generate(glyphs.data(), glyphs.size());
// The atlas bitmap can now be retrieved via atlasStorage as a BitmapConstRef.
// The glyphs array (or fontGeometry) contains positioning data for typesetting text.
success = submitAtlasBitmapAndLayout((msdfgen::BitmapConstRef <float, 3>)generator.atlasStorage(),
glyphs,
width,
height);
// Cleanup
msdfgen::destroyFont(font);
}
msdfgen::deinitializeFreetype(ft);
}
return success;
}
bool ofxMsdfgen::submitAtlasBitmapAndLayout(const msdfgen::BitmapConstRef <float, 3> & storage,
const std::vector <msdf_atlas::GlyphGeometry> & glyphs,
const int & width,
const int & height){
const msdfgen::Bitmap <float, 3> bitmap(storage);
ofImage image;
toOfImage(bitmap, image);
image.save("atlas.png");
return true;
}