mirror
/
msdfgen
mirror of https://github.com/Chlumsky/msdfgen.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
msdfgen/c/msdfgen.c

274 lines
14 KiB
C
Raw Blame History

#include "msdfgen-c.h"
#include <math.h>
#include <float.h>
#include "equation-solver.h"
#define DISTANCE_DELTA_FACTOR 1.001
//#define MSDFGEN_IF_CACHE_AND(...) // disable cache
#define MSDFGEN_IF_CACHE_AND if
extern long long MSDFGEN_PERFSTATS_CACHE_TESTS;
extern long long MSDFGEN_PERFSTATS_CACHE_MISSES;
long long MSDFGEN_PERFSTATS_CACHE_TESTS = 0;
long long MSDFGEN_PERFSTATS_CACHE_MISSES = 0;
#define MSDFGEN_PERFSTATS_CACHE_TEST() (++MSDFGEN_PERFSTATS_CACHE_TESTS)
#define MSDFGEN_PERFSTATS_CACHE_MISS() (++MSDFGEN_PERFSTATS_CACHE_MISSES)
//#define NO_CACHE_AND_SQUARE_DISTANCE
#ifdef __cplusplus
extern "C" {
#endif
static int nonZeroSign(MSDFGEN_real x) {
return x > (MSDFGEN_real) 0 ? 1 : -1;
}
static int crossNonZeroSign(MSDFGEN_Vector2 a, MSDFGEN_Vector2 b) {
return a.x*b.y > b.x*a.y ? 1 : -1;
}
size_t MSDFGEN_TrueDistanceCache_size(const MSDFGEN_CompiledShape *shapePtr) {
return sizeof(MSDFGEN_TrueDistanceCache) + (shapePtr->nLinearEdges+shapePtr->nQuadraticEdges+shapePtr->nCubicEdges)*sizeof(MSDFGEN_TrueDistanceEdgeCache);
}
void MSDFGEN_TrueDistanceCache_initialize(MSDFGEN_TrueDistanceCache *cachePtr, const MSDFGEN_CompiledShape *shapePtr) {
MSDFGEN_TrueDistanceEdgeCache *cur, *end;
cachePtr->origin.x = 0;
cachePtr->origin.y = 0;
cachePtr->minDistance = .0625f*FLT_MAX;
for (cur = cachePtr->edgeData, end = cachePtr->edgeData+(shapePtr->nLinearEdges+shapePtr->nQuadraticEdges+shapePtr->nCubicEdges); cur < end; ++cur) {
#if MSDFGEN_ABTEST_ALT_CACHE
cur->origin.x = 0;
cur->origin.y = 0;
#else
cur->edgeDistance = 0;
#endif
}
}
#ifdef NO_CACHE_AND_SQUARE_DISTANCE
// INCOMPLETE !!!!
MSDFGEN_real MSDFGEN_signedDistance(const MSDFGEN_CompiledShape *shapePtr, MSDFGEN_Vector2 origin, MSDFGEN_TrueDistanceCache *cachePtr) {
int sign = -1;
MSDFGEN_real sqd = FLT_MAX;
size_t i;
for (i = 0; i < shapePtr->nLinearEdges; ++i) {
MSDFGEN_Vector2 originP0 = MSDFGEN_Vector2_difference(shapePtr->linearEdges[i].endpoint0, origin);
MSDFGEN_real originP0SqD = MSDFGEN_Vector2_squaredLength(originP0);
MSDFGEN_real t = MSDFGEN_Vector2_dot(originP0, shapePtr->linearEdges[i].invDerivative);
if (originP0SqD < sqd) {
sqd = originP0SqD;
sign = crossNonZeroSign(shapePtr->linearEdges[i].cornerVec0, MSDFGEN_Vector2_sum(shapePtr->linearEdges[i].direction, originP0));
}
if (t > (MSDFGEN_real) 0 && t < (MSDFGEN_real) 1) {
MSDFGEN_real pd = MSDFGEN_Vector2_cross(shapePtr->linearEdges[i].direction, originP0);
MSDFGEN_real sqpd = pd*pd;
if (sqpd < sqd) {
sqd = sqpd;
sign = nonZeroSign(pd);
}
}
}
for (i = 0; i < shapePtr->nQuadraticEdges; ++i) {
MSDFGEN_Vector2 originP0 = MSDFGEN_Vector2_difference(shapePtr->quadraticEdges[i].endpoint0, origin);
MSDFGEN_real originP0SqD = MSDFGEN_Vector2_squaredLength(originP0);
MSDFGEN_real a = MSDFGEN_Vector2_squaredLength(shapePtr->quadraticEdges[i].derivative1);
MSDFGEN_real b = (MSDFGEN_real) 3*MSDFGEN_Vector2_dot(shapePtr->quadraticEdges[i].derivative0, shapePtr->quadraticEdges[i].derivative1);
MSDFGEN_real c = (MSDFGEN_real) 2*MSDFGEN_Vector2_squaredLength(shapePtr->quadraticEdges[i].derivative0) + MSDFGEN_Vector2_dot(originP0, shapePtr->quadraticEdges[i].derivative1);
MSDFGEN_real d = MSDFGEN_Vector2_dot(originP0, shapePtr->quadraticEdges[i].derivative0);
double t[3];
int solutions = MSDFGEN_solveCubic(t, a, b, c, d);
if (originP0SqD < sqd) {
sqd = originP0SqD;
sign = crossNonZeroSign(shapePtr->quadraticEdges[i].cornerVec0, MSDFGEN_Vector2_sum(shapePtr->quadraticEdges[i].direction0, originP0));
}
#define MSDFGEN_SD_RESOLVE_QUADRATIC_SOLUTION(t) if (t > 0 && t < 1) { \
MSDFGEN_Vector2 originP = MSDFGEN_Vector2_sum(MSDFGEN_Vector2_sum(originP0, MSDFGEN_Vector2_scale((MSDFGEN_real) (2*t), shapePtr->quadraticEdges[i].derivative0)), MSDFGEN_Vector2_scale((MSDFGEN_real) (t*t), shapePtr->quadraticEdges[i].derivative1)); \
MSDFGEN_real originPSqD = MSDFGEN_Vector2_squaredLength(originP); \
if (originPSqD < sqd) { \
MSDFGEN_Vector2 direction = MSDFGEN_Vector2_sum(shapePtr->quadraticEdges[i].derivative0, MSDFGEN_Vector2_scale(t, shapePtr->quadraticEdges[i].derivative1)); \
sqd = originPSqD; \
sign = crossNonZeroSign(direction, originP); \
} \
}
if (solutions > 0) {
MSDFGEN_SD_RESOLVE_QUADRATIC_SOLUTION(t[0]);
if (solutions > 1) {
MSDFGEN_SD_RESOLVE_QUADRATIC_SOLUTION(t[1]);
if (solutions > 2)
MSDFGEN_SD_RESOLVE_QUADRATIC_SOLUTION(t[2]);
}
}
}
return (MSDFGEN_real) sign*sqrt(sqd);
}
#else
#if MSDFGEN_ABTEST_ALT_CACHE
#define MSDFGEN_IF_TRUE_DISTANCE_UNCACHED MSDFGEN_PERFSTATS_CACHE_TEST(); MSDFGEN_IF_CACHE_AND(++edgeCache, edgeCache[-1].edgeDistance-DISTANCE_DELTA_FACTOR*sqrt(MSDFGEN_Vector2_squaredLength(MSDFGEN_Vector2_difference(origin, edgeCache[-1].origin))) <= minDistance)
#else
#define MSDFGEN_IF_TRUE_DISTANCE_UNCACHED MSDFGEN_PERFSTATS_CACHE_TEST(); MSDFGEN_IF_CACHE_AND((edgeCache++->edgeDistance -= cacheDelta) <= minDistance)
#endif
MSDFGEN_real MSDFGEN_signedDistance(const MSDFGEN_CompiledShape *shapePtr, MSDFGEN_Vector2 origin, MSDFGEN_TrueDistanceCache *cachePtr) {
MSDFGEN_real cacheDelta = DISTANCE_DELTA_FACTOR*sqrt(MSDFGEN_Vector2_squaredLength(MSDFGEN_Vector2_difference(origin, cachePtr->origin)));
MSDFGEN_real minDistance = cachePtr->minDistance+cacheDelta;
int distanceSign = -1;
MSDFGEN_TrueDistanceEdgeCache *edgeCache = cachePtr->edgeData;
size_t i;
for (i = 0; i < shapePtr->nLinearEdges; ++i) {
MSDFGEN_IF_TRUE_DISTANCE_UNCACHED {
MSDFGEN_Vector2 originP0 = MSDFGEN_Vector2_difference(shapePtr->linearEdges[i].endpoint0, origin);
MSDFGEN_real originP0Dist = sqrt(MSDFGEN_Vector2_squaredLength(originP0));
MSDFGEN_real t = MSDFGEN_Vector2_dot(originP0, shapePtr->linearEdges[i].invDerivative);
if (originP0Dist < minDistance) {
minDistance = originP0Dist;
distanceSign = crossNonZeroSign(shapePtr->linearEdges[i].cornerVec0, MSDFGEN_Vector2_sum(shapePtr->linearEdges[i].direction, originP0));
}
edgeCache[-1].edgeDistance = originP0Dist;
if (t > (MSDFGEN_real) 0 && t < (MSDFGEN_real) 1) {
MSDFGEN_real psd = MSDFGEN_Vector2_cross(shapePtr->linearEdges[i].direction, originP0);
MSDFGEN_real pd = fabs(psd);
if (pd < minDistance) {
minDistance = pd;
distanceSign = nonZeroSign(psd);
}
edgeCache[-1].edgeDistance = pd;
} else {
MSDFGEN_real originP1Dist = sqrt(MSDFGEN_Vector2_squaredLength(MSDFGEN_Vector2_difference(shapePtr->linearEdges[i].endpoint1, origin)));
if (originP1Dist < edgeCache[-1].edgeDistance)
edgeCache[-1].edgeDistance = originP1Dist;
}
MSDFGEN_PERFSTATS_CACHE_MISS();
#if MSDFGEN_ABTEST_ALT_CACHE
edgeCache[-1].origin = origin;
#endif
}
}
for (i = 0; i < shapePtr->nQuadraticEdges; ++i) {
MSDFGEN_IF_TRUE_DISTANCE_UNCACHED {
MSDFGEN_Vector2 originP0 = MSDFGEN_Vector2_difference(shapePtr->quadraticEdges[i].endpoint0, origin);
MSDFGEN_real originP0Dist = sqrt(MSDFGEN_Vector2_squaredLength(originP0));
MSDFGEN_real originP1Dist = sqrt(MSDFGEN_Vector2_squaredLength(MSDFGEN_Vector2_difference(shapePtr->quadraticEdges[i].endpoint1, origin)));
MSDFGEN_real a = MSDFGEN_Vector2_squaredLength(shapePtr->quadraticEdges[i].derivative1);
MSDFGEN_real b = (MSDFGEN_real) 3*MSDFGEN_Vector2_dot(shapePtr->quadraticEdges[i].derivative0, shapePtr->quadraticEdges[i].derivative1);
MSDFGEN_real c = (MSDFGEN_real) 2*MSDFGEN_Vector2_squaredLength(shapePtr->quadraticEdges[i].derivative0) + MSDFGEN_Vector2_dot(originP0, shapePtr->quadraticEdges[i].derivative1);
MSDFGEN_real d = MSDFGEN_Vector2_dot(originP0, shapePtr->quadraticEdges[i].derivative0);
double t[3];
int solutions = MSDFGEN_solveCubic(t, a, b, c, d);
if (originP0Dist < minDistance) {
minDistance = originP0Dist;
distanceSign = crossNonZeroSign(shapePtr->quadraticEdges[i].cornerVec0, MSDFGEN_Vector2_sum(shapePtr->quadraticEdges[i].direction0, originP0));
}
edgeCache[-1].edgeDistance = originP0Dist;
if (originP1Dist < edgeCache[-1].edgeDistance)
edgeCache[-1].edgeDistance = originP1Dist;
#define MSDFGEN_SD_RESOLVE_QUADRATIC_SOLUTION(t) if (t > 0 && t < 1) { \
MSDFGEN_Vector2 originP = MSDFGEN_Vector2_sum(MSDFGEN_Vector2_sum(originP0, MSDFGEN_Vector2_scale((MSDFGEN_real) (2*t), shapePtr->quadraticEdges[i].derivative0)), MSDFGEN_Vector2_scale((MSDFGEN_real) (t*t), shapePtr->quadraticEdges[i].derivative1)); \
MSDFGEN_real originPDist = sqrt(MSDFGEN_Vector2_squaredLength(originP)); \
if (originPDist < minDistance) { \
MSDFGEN_Vector2 direction = MSDFGEN_Vector2_sum(shapePtr->quadraticEdges[i].derivative0, MSDFGEN_Vector2_scale(t, shapePtr->quadraticEdges[i].derivative1)); \
minDistance = originPDist; \
distanceSign = crossNonZeroSign(direction, originP); \
} \
if (originPDist < edgeCache[-1].edgeDistance) \
edgeCache[-1].edgeDistance = originPDist; \
}
if (solutions > 0) {
MSDFGEN_SD_RESOLVE_QUADRATIC_SOLUTION(t[0]);
if (solutions > 1) {
MSDFGEN_SD_RESOLVE_QUADRATIC_SOLUTION(t[1]);
if (solutions > 2)
MSDFGEN_SD_RESOLVE_QUADRATIC_SOLUTION(t[2]);
}
}
MSDFGEN_PERFSTATS_CACHE_MISS();
#if MSDFGEN_ABTEST_ALT_CACHE
edgeCache[-1].origin = origin;
#endif
}
}
for (i = 0; i < shapePtr->nCubicEdges; ++i) {
MSDFGEN_IF_TRUE_DISTANCE_UNCACHED {
int start, step;
MSDFGEN_Vector2 originP0 = MSDFGEN_Vector2_difference(shapePtr->cubicEdges[i].endpoint0, origin);
MSDFGEN_real originP0Dist = sqrt(MSDFGEN_Vector2_squaredLength(originP0));
MSDFGEN_real originP1Dist = sqrt(MSDFGEN_Vector2_squaredLength(MSDFGEN_Vector2_difference(shapePtr->cubicEdges[i].endpoint1, origin)));
if (originP0Dist < minDistance) {
minDistance = originP0Dist;
distanceSign = crossNonZeroSign(shapePtr->cubicEdges[i].cornerVec0, MSDFGEN_Vector2_sum(shapePtr->cubicEdges[i].direction0, originP0));
}
edgeCache[-1].edgeDistance = originP0Dist;
if (originP1Dist < edgeCache[-1].edgeDistance)
edgeCache[-1].edgeDistance = originP1Dist;
for (start = 0; start <= MSDFGEN_CUBIC_SEARCH_STARTS; ++start) {
MSDFGEN_real t = (MSDFGEN_real) 1/(MSDFGEN_real) MSDFGEN_CUBIC_SEARCH_STARTS*(MSDFGEN_real) start;
MSDFGEN_Vector2 originP = MSDFGEN_Vector2_sum(
MSDFGEN_Vector2_sum(
MSDFGEN_Vector2_sum(originP0, MSDFGEN_Vector2_scale((MSDFGEN_real) 3*t, shapePtr->cubicEdges[i].derivative0)),
MSDFGEN_Vector2_scale((MSDFGEN_real) 3*(t*t), shapePtr->cubicEdges[i].derivative1)
), MSDFGEN_Vector2_scale(t*t*t, shapePtr->cubicEdges[i].derivative2)
);
for (step = 0; step < MSDFGEN_CUBIC_SEARCH_STEPS; ++step) {
MSDFGEN_Vector2 derivative0 = MSDFGEN_Vector2_sum(
MSDFGEN_Vector2_sum(
MSDFGEN_Vector2_scale((MSDFGEN_real) 3, shapePtr->cubicEdges[i].derivative0),
MSDFGEN_Vector2_scale((MSDFGEN_real) 6*t, shapePtr->cubicEdges[i].derivative1)
), MSDFGEN_Vector2_scale((MSDFGEN_real) 3*(t*t), shapePtr->cubicEdges[i].derivative2)
);
MSDFGEN_Vector2 derivative1 = MSDFGEN_Vector2_sum(
MSDFGEN_Vector2_scale((MSDFGEN_real) 6, shapePtr->cubicEdges[i].derivative1),
MSDFGEN_Vector2_scale((MSDFGEN_real) 6*t, shapePtr->cubicEdges[i].derivative2)
);
t -= MSDFGEN_Vector2_dot(originP, derivative0)/(MSDFGEN_Vector2_squaredLength(derivative0)+MSDFGEN_Vector2_dot(originP, derivative1));
if (t <= (MSDFGEN_real) 0 || t >= (MSDFGEN_real) 1)
break;
originP = MSDFGEN_Vector2_sum(
MSDFGEN_Vector2_sum(
MSDFGEN_Vector2_sum(originP0, MSDFGEN_Vector2_scale((MSDFGEN_real) 3*t, shapePtr->cubicEdges[i].derivative0)),
MSDFGEN_Vector2_scale((MSDFGEN_real) 3*(t*t), shapePtr->cubicEdges[i].derivative1)
), MSDFGEN_Vector2_scale(t*t*t, shapePtr->cubicEdges[i].derivative2)
);
MSDFGEN_real originPDist = sqrt(MSDFGEN_Vector2_squaredLength(originP));
if (originPDist < minDistance) {
minDistance = originPDist;
distanceSign = crossNonZeroSign(derivative0, originP);
}
if (originPDist < edgeCache[-1].edgeDistance)
edgeCache[-1].edgeDistance = originPDist;
}
}
MSDFGEN_PERFSTATS_CACHE_MISS();
#if MSDFGEN_ABTEST_ALT_CACHE
edgeCache[-1].origin = origin;
#endif
}
}
cachePtr->origin = origin;
cachePtr->minDistance = minDistance;
return (MSDFGEN_real) distanceSign*minDistance;
}
#endif
#ifdef __cplusplus
}
#endif
Reference in New Issue View Git Blame Copy Permalink