diff --git a/core/MSDFErrorCorrection.cpp b/core/MSDFErrorCorrection.cpp index 2a8fdf1..aaa6a86 100644 --- a/core/MSDFErrorCorrection.cpp +++ b/core/MSDFErrorCorrection.cpp @@ -5,19 +5,120 @@ #include "arithmetics.hpp" #include "equation-solver.h" #include "EdgeColor.h" +#include "bitmap-interpolation.hpp" +#include "edge-selectors.h" +#include "contour-combiners.h" +#include "ShapeDistanceFinder.h" +#include "generator-config.h" namespace msdfgen { #define ARTIFACT_T_EPSILON .01 #define PROTECTION_RADIUS_TOLERANCE 1.001 +#define CLASSIFIER_FLAG_CANDIDATE 0x01 +#define CLASSIFIER_FLAG_ARTIFACT 0x02 + +const double ErrorCorrectionConfig::defaultMinDeviationRatio = 1.11111111111111111; +const double ErrorCorrectionConfig::defaultMinImproveRatio = 1.11111111111111111; + +/// The base artifact classifier recognizes artifacts based on the contents of the SDF alone. +class BaseArtifactClassifier { +public: + inline BaseArtifactClassifier(double span, bool protectedFlag) : span(span), protectedFlag(protectedFlag) { } + /// Evaluates if the median value xm interpolated at xt in the range between am at at and bm at bt indicates an artifact. + inline int rangeTest(double at, double bt, double xt, float am, float bm, float xm) const { + // For protected texels, only consider inversion artifacts (interpolated median has different sign than boundaries). For the rest, it is sufficient that the interpolated median is outside its boundaries. + if ((am > .5f && bm > .5f && xm < .5f) || (am < .5f && bm < .5f && xm > .5f) || (!protectedFlag && median(am, bm, xm) != xm)) { + double axSpan = (xt-at)*span, bxSpan = (bt-xt)*span; + // Check if the interpolated median's value is in the expected range based on its distance (span) from boundaries a, b. + if (!(xm >= am-axSpan && xm <= am+axSpan && xm >= bm-bxSpan && xm <= bm+bxSpan)) + return CLASSIFIER_FLAG_CANDIDATE|CLASSIFIER_FLAG_ARTIFACT; + return CLASSIFIER_FLAG_CANDIDATE; + } + return 0; + } + /// Returns true if the combined results of the tests performed on the median value m interpolated at t indicate an artifact. + inline bool evaluate(double t, float m, int flags) const { + return (flags&2) != 0; + } +private: + double span; + bool protectedFlag; +}; + +/// The shape distance checker evaluates the exact shape distance to find additional artifacts at a significant performance cost. +template