Added -coloringstrategy option, version 1.2

.gitignore

@@ -13,6 +13,7 @@ x64/
 *.suo
 *.VC.opendb
 *.VC.db
+bin/msdf-atlas-gen
 bin/*.lib
 output.png
 out/

CHANGELOG.md

@@ -1,4 +1,12 @@
 
+## Version 1.2 (2021-05-29)
+
+- Updated to MSDFgen 1.9.
+- Multiple fonts or font sizes can now be compiled into a single atlas.
+- Added `-yorigin` option to choose if Y-coordinates increase from bottom to top or from top to bottom.
+- Added `-coloringstrategy` option to select MSDF edge coloring heuristic.
+- Shadron preview now properly loads floating-point image outputs in full range mode.
+
 ## Version 1.1 (2020-10-18)
 
 - Updated to MSDFgen 1.8.

README.md

@@ -108,14 +108,17 @@ Any non-empty subset of the following may be specified:
 ### Distance field generator settings
 
 - `-angle <angle>` &ndash; sets the minimum angle between adjacent edges to be considered a corner. Append D for degrees (`msdf` / `mtsdf` only)
-- `-errorcorrection <threshold>` &ndash; sets the threshold used to detect and correct potential artifacts. 0 disables error correction (`msdf` / `mtsdf` only)
+- `-coloringstrategy <simple / inktrap / distance>` &ndash; selects the edge coloring heuristic (`msdf` / `mtsdf` only)
+- `-errorcorrection <mode>` &ndash; selects the error correction algorithm. Use `help` as mode for more information (`msdf` / `mtsdf` only)
 - `-miterlimit <value>` &ndash; sets the miter limit that limits the extension of each glyph's bounding box due to very sharp corners (`psdf` / `msdf` / `mtsdf` only)
 - `-overlap` &ndash; switches to distance field generator with support for overlapping contours
 - `-nopreprocess` &ndash; disables path preprocessing which resolves self-intersections and overlapping contours
 - `-scanline` &ndash; performs an additional scanline pass to fix the signs of the distances
 - `-seed <N>` &ndash; sets the initial seed for the edge coloring heuristic
 - `-threads <N>` &ndash; sets the number of threads for the parallel computation (0 = auto)
 
+Use `-help` for an exhaustive list of options.
+
 ## Character set specification syntax
 
 The character set file is a text file with UTF-8 or ASCII encoding.

msdf-atlas-gen/GlyphGeometry.cpp

@@ -47,8 +47,8 @@ bool GlyphGeometry::load(msdfgen::FontHandle *font, double geometryScale, unicod
     return false;
 }
 
-void GlyphGeometry::edgeColoring(double angleThreshold, unsigned long long seed) {
-    msdfgen::edgeColoringInkTrap(shape, angleThreshold, seed);
+void GlyphGeometry::edgeColoring(void (*fn)(msdfgen::Shape &, double, unsigned long long), double angleThreshold, unsigned long long seed) {
+    fn(shape, angleThreshold, seed);
 }
 
 void GlyphGeometry::wrapBox(double scale, double range, double miterLimit) {

msdf-atlas-gen/GlyphGeometry.h

@@ -17,7 +17,7 @@ class GlyphGeometry {
     bool load(msdfgen::FontHandle *font, double geometryScale, msdfgen::GlyphIndex index, bool preprocessGeometry = true);
     bool load(msdfgen::FontHandle *font, double geometryScale, unicode_t codepoint, bool preprocessGeometry = true);
     /// Applies edge coloring to glyph shape
-    void edgeColoring(double angleThreshold, unsigned long long seed);
+    void edgeColoring(void (*fn)(msdfgen::Shape &, double, unsigned long long), double angleThreshold, unsigned long long seed);
     /// Computes the dimensions of the glyph's box as well as the transformation for the generator function
     void wrapBox(double scale, double range, double miterLimit);
     /// Sets the glyph's box's position in the atlas

msdf-atlas-gen/main.cpp

@@ -1,8 +1,8 @@
 
 /*
-* MULTI-CHANNEL SIGNED DISTANCE FIELD ATLAS GENERATOR v1.1 (2020-10-18) - standalone console program
+* MULTI-CHANNEL SIGNED DISTANCE FIELD ATLAS GENERATOR v1.2 (2021-05-29) - standalone console program
 * --------------------------------------------------------------------------------------------------
-* A utility by Viktor Chlumsky, (c) 2020
+* A utility by Viktor Chlumsky, (c) 2020 - 2021
 *
 */
 
@@ -26,7 +26,8 @@ using namespace msdf_atlas;
 #define DEFAULT_PIXEL_RANGE 2.0
 #define SDF_ERROR_ESTIMATE_PRECISION 19
 #define GLYPH_FILL_RULE msdfgen::FILL_NONZERO
-#define MCG_MULTIPLIER 6364136223846793005ull
+#define LCG_MULTIPLIER 6364136223846793005ull
+#define LCG_INCREMENT 1442695040888963407ull
 
 #ifdef MSDFGEN_USE_SKIA
     #define TITLE_SUFFIX    " & Skia"
@@ -94,6 +95,8 @@ GLYPH CONFIGURATION
 DISTANCE FIELD GENERATOR SETTINGS
   -angle <angle>
       Specifies the minimum angle between adjacent edges to be considered a corner. Append D for degrees. (msdf / mtsdf only)
+  -coloringstrategy <simple / inktrap / distance>
+      Selects the strategy of the edge coloring heuristic.
   -errorcorrection <mode>
       Changes the MSDF/MTSDF error correction mode. Use -errorcorrection help for a list of valid modes.
   -errordeviationratio <ratio>
@@ -201,6 +204,8 @@ struct Configuration {
     double pxRange;
     double angleThreshold;
     double miterLimit;
+    void (*edgeColoring)(msdfgen::Shape &, double, unsigned long long);
+    bool expensiveColoring;
     unsigned long long coloringSeed;
     GeneratorAttributes generatorAttributes;
     bool preprocessGeometry;
@@ -263,6 +268,7 @@ int main(int argc, const char * const *argv) {
     config.imageType = ImageType::MSDF;
     config.imageFormat = ImageFormat::UNSPECIFIED;
     config.yDirection = YDirection::BOTTOM_UP;
+    config.edgeColoring = msdfgen::edgeColoringInkTrap;
     config.kerning = true;
     const char *imageFormatName = nullptr;
     int fixedWidth = -1, fixedHeight = -1;
@@ -547,6 +553,15 @@ int main(int argc, const char * const *argv) {
             argPos += 2;
             continue;
         }
+        ARG_CASE("-coloringstrategy", 1) {
+            if (!strcmp(argv[argPos+1], "simple")) config.edgeColoring = msdfgen::edgeColoringSimple, config.expensiveColoring = false;
+            else if (!strcmp(argv[argPos+1], "inktrap")) config.edgeColoring = msdfgen::edgeColoringInkTrap, config.expensiveColoring = false;
+            else if (!strcmp(argv[argPos+1], "distance")) config.edgeColoring = msdfgen::edgeColoringByDistance, config.expensiveColoring = true;
+            else
+                puts("Unknown coloring strategy specified.");
+            argPos += 2;
+            continue;
+        }
         ARG_CASE("-miterlimit", 1) {
             double m;
             if (!(parseDouble(m, argv[++argPos]) && m >= 0))
@@ -891,10 +906,18 @@ int main(int argc, const char * const *argv) {
 
         // Edge coloring
         if (config.imageType == ImageType::MSDF || config.imageType == ImageType::MTSDF) {
-            unsigned long long glyphSeed = config.coloringSeed;
-            for (GlyphGeometry &glyph : glyphs) {
-                glyphSeed *= MCG_MULTIPLIER;
-                glyph.edgeColoring(config.angleThreshold, glyphSeed);
+            if (config.expensiveColoring) {
+                Workload([&glyphs, &config](int i, int threadNo) -> bool {
+                    unsigned long long glyphSeed = (LCG_MULTIPLIER*(config.coloringSeed^i)+LCG_INCREMENT)*!!config.coloringSeed;
+                    glyphs[i].edgeColoring(config.edgeColoring, config.angleThreshold, glyphSeed);
+                    return true;
+                }, glyphs.size()).finish(config.threadCount);
+            } else {
+                unsigned long long glyphSeed = config.coloringSeed;
+                for (GlyphGeometry &glyph : glyphs) {
+                    glyphSeed *= LCG_MULTIPLIER;
+                    glyph.edgeColoring(config.edgeColoring, config.angleThreshold, glyphSeed);
+                }
             }
         }
 

msdf-atlas-gen/msdf-atlas-gen.h

@@ -2,9 +2,9 @@
 #pragma once
 
 /*
- * MULTI-CHANNEL SIGNED DISTANCE FIELD ATLAS GENERATOR v1.1 (2020-10-18)
+ * MULTI-CHANNEL SIGNED DISTANCE FIELD ATLAS GENERATOR v1.2 (2021-05-29)
  * ---------------------------------------------------------------------
- * A utility by Viktor Chlumsky, (c) 2020
+ * A utility by Viktor Chlumsky, (c) 2020 - 2021
  *
  * Generates compact bitmap font atlases using MSDFGEN.
  *
@@ -39,4 +39,4 @@
 #include "json-export.h"
 #include "shadron-preview-generator.h"
 
-#define MSDF_ATLAS_VERSION "1.1"
+#define MSDF_ATLAS_VERSION "1.2"