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nanosvgrast.h
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nanosvgrast.h
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/*
* Copyright (c) 2013-14 Mikko Mononen [email protected]
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*
* The polygon rasterization is heavily based on stb_truetype rasterizer
* by Sean Barrett - http://nothings.org/
*
*/
#ifndef NANOSVGRAST_H
#define NANOSVGRAST_H
#ifndef NSVG_EXPORT
#define NSVG_EXPORT
#endif
#ifndef NANOSVGRAST_CPLUSPLUS
#ifdef __cplusplus
extern "C" {
#endif
#endif
typedef struct NSVGrasterizer NSVGrasterizer;
/* Example Usage:
// Load SVG
NSVGimage* image;
image = nsvgParseFromFile("test.svg", "px", 96);
// Create rasterizer (can be used to render multiple images).
struct NSVGrasterizer* rast = nsvgCreateRasterizer();
// Allocate memory for image
unsigned char* img = malloc(w*h*4);
// Rasterize
nsvgRasterize(rast, image, 0,0,1, img, w, h, w*4);
*/
// Allocated rasterizer context.
NSVG_EXPORT NSVGrasterizer* nsvgCreateRasterizer(void);
// Rasterizes SVG image, returns RGBA image (non-premultiplied alpha)
// r - pointer to rasterizer context
// image - pointer to image to rasterize
// tx,ty - image offset (applied after scaling)
// scale - image scale
// dst - pointer to destination image data, 4 bytes per pixel (RGBA)
// w - width of the image to render
// h - height of the image to render
// stride - number of bytes per scaleline in the destination buffer
NSVG_EXPORT void nsvgRasterize(NSVGrasterizer* r,
NSVGimage* image, float tx, float ty, float scale,
unsigned char* dst, int w, int h, int stride);
// Deletes rasterizer context.
NSVG_EXPORT void nsvgDeleteRasterizer(NSVGrasterizer*);
#ifndef NANOSVGRAST_CPLUSPLUS
#ifdef __cplusplus
}
#endif
#endif
#ifdef NANOSVGRAST_IMPLEMENTATION
/*
#include <math.h>
*/
#define NSVG__SUBSAMPLES 5
#define NSVG__FIXSHIFT 10
#define NSVG__FIX (1 << NSVG__FIXSHIFT)
#define NSVG__FIXMASK (NSVG__FIX-1)
#define NSVG__MEMPAGE_SIZE 1024
typedef struct NSVGedge {
float x0,y0, x1,y1;
int dir;
struct NSVGedge* next;
} NSVGedge;
typedef struct NSVGpoint {
float x, y;
float dx, dy;
float len;
float dmx, dmy;
unsigned char flags;
} NSVGpoint;
typedef struct NSVGactiveEdge {
int x,dx;
float ey;
int dir;
struct NSVGactiveEdge *next;
} NSVGactiveEdge;
typedef struct NSVGmemPage {
unsigned char mem[NSVG__MEMPAGE_SIZE];
int size;
struct NSVGmemPage* next;
} NSVGmemPage;
typedef struct NSVGcachedPaint {
char type;
char spread;
float xform[6];
unsigned int colors[256];
} NSVGcachedPaint;
struct NSVGrasterizer
{
float px, py;
float tessTol;
float distTol;
NSVGedge* edges;
int nedges;
int cedges;
NSVGpoint* points;
int npoints;
int cpoints;
NSVGpoint* points2;
int npoints2;
int cpoints2;
NSVGactiveEdge* freelist;
NSVGmemPage* pages;
NSVGmemPage* curpage;
unsigned char* scanline;
int cscanline;
unsigned char* bitmap;
int width, height, stride;
};
NSVG_EXPORT NSVGrasterizer* nsvgCreateRasterizer(void)
{
NSVGrasterizer* r = (NSVGrasterizer*)malloc(sizeof(NSVGrasterizer));
if (r == NULL) goto error;
memset(r, 0, sizeof(NSVGrasterizer));
r->tessTol = 0.25f;
r->distTol = 0.01f;
return r;
error:
nsvgDeleteRasterizer(r);
return NULL;
}
NSVG_EXPORT void nsvgDeleteRasterizer(NSVGrasterizer* r)
{
NSVGmemPage* p;
if (r == NULL) return;
p = r->pages;
while (p != NULL) {
NSVGmemPage* next = p->next;
free(p);
p = next;
}
if (r->edges) free(r->edges);
if (r->points) free(r->points);
if (r->points2) free(r->points2);
if (r->scanline) free(r->scanline);
free(r);
}
static NSVGmemPage* nsvg__nextPage(NSVGrasterizer* r, NSVGmemPage* cur)
{
NSVGmemPage *newp;
// If using existing chain, return the next page in chain
if (cur != NULL && cur->next != NULL) {
return cur->next;
}
// Alloc new page
newp = (NSVGmemPage*)malloc(sizeof(NSVGmemPage));
if (newp == NULL) return NULL;
memset(newp, 0, sizeof(NSVGmemPage));
// Add to linked list
if (cur != NULL)
cur->next = newp;
else
r->pages = newp;
return newp;
}
static void nsvg__resetPool(NSVGrasterizer* r)
{
NSVGmemPage* p = r->pages;
while (p != NULL) {
p->size = 0;
p = p->next;
}
r->curpage = r->pages;
}
static unsigned char* nsvg__alloc(NSVGrasterizer* r, int size)
{
unsigned char* buf;
if (size > NSVG__MEMPAGE_SIZE) return NULL;
if (r->curpage == NULL || r->curpage->size+size > NSVG__MEMPAGE_SIZE) {
r->curpage = nsvg__nextPage(r, r->curpage);
}
buf = &r->curpage->mem[r->curpage->size];
r->curpage->size += size;
return buf;
}
static int nsvg__ptEquals(float x1, float y1, float x2, float y2, float tol)
{
float dx = x2 - x1;
float dy = y2 - y1;
return dx*dx + dy*dy < tol*tol;
}
static void nsvg__addPathPoint(NSVGrasterizer* r, float x, float y, int flags)
{
NSVGpoint* pt;
if (r->npoints > 0) {
pt = &r->points[r->npoints-1];
if (nsvg__ptEquals(pt->x,pt->y, x,y, r->distTol)) {
pt->flags = (unsigned char)(pt->flags | flags);
return;
}
}
if (r->npoints+1 > r->cpoints) {
r->cpoints = r->cpoints > 0 ? r->cpoints * 2 : 64;
r->points = (NSVGpoint*)realloc(r->points, sizeof(NSVGpoint) * r->cpoints);
if (r->points == NULL) return;
}
pt = &r->points[r->npoints];
pt->x = x;
pt->y = y;
pt->flags = (unsigned char)flags;
r->npoints++;
}
static void nsvg__appendPathPoint(NSVGrasterizer* r, NSVGpoint pt)
{
if (r->npoints+1 > r->cpoints) {
r->cpoints = r->cpoints > 0 ? r->cpoints * 2 : 64;
r->points = (NSVGpoint*)realloc(r->points, sizeof(NSVGpoint) * r->cpoints);
if (r->points == NULL) return;
}
r->points[r->npoints] = pt;
r->npoints++;
}
static void nsvg__duplicatePoints(NSVGrasterizer* r)
{
if (r->npoints > r->cpoints2) {
r->cpoints2 = r->npoints;
r->points2 = (NSVGpoint*)realloc(r->points2, sizeof(NSVGpoint) * r->cpoints2);
if (r->points2 == NULL) return;
}
memcpy(r->points2, r->points, sizeof(NSVGpoint) * r->npoints);
r->npoints2 = r->npoints;
}
static void nsvg__addEdge(NSVGrasterizer* r, float x0, float y0, float x1, float y1)
{
NSVGedge* e;
// Skip horizontal edges
if (y0 == y1)
return;
if (r->nedges+1 > r->cedges) {
r->cedges = r->cedges > 0 ? r->cedges * 2 : 64;
r->edges = (NSVGedge*)realloc(r->edges, sizeof(NSVGedge) * r->cedges);
if (r->edges == NULL) return;
}
e = &r->edges[r->nedges];
r->nedges++;
if (y0 < y1) {
e->x0 = x0;
e->y0 = y0;
e->x1 = x1;
e->y1 = y1;
e->dir = 1;
} else {
e->x0 = x1;
e->y0 = y1;
e->x1 = x0;
e->y1 = y0;
e->dir = -1;
}
}
static float nsvg__normalize(float *x, float* y)
{
float d = sqrtf((*x)*(*x) + (*y)*(*y));
if (d > 1e-6f) {
float id = 1.0f / d;
*x *= id;
*y *= id;
}
return d;
}
static float nsvg__absf(float x) { return x < 0 ? -x : x; }
static void nsvg__flattenCubicBez(NSVGrasterizer* r,
float x1, float y1, float x2, float y2,
float x3, float y3, float x4, float y4,
int level, int type)
{
const int max_level = 10;
float x12,y12,x23,y23,x34,y34,x123,y123,x234,y234,x1234,y1234;
float dx,dy,d2,d3;
if (level > max_level) return;
x12 = (x1+x2)*0.5f;
y12 = (y1+y2)*0.5f;
x23 = (x2+x3)*0.5f;
y23 = (y2+y3)*0.5f;
x34 = (x3+x4)*0.5f;
y34 = (y3+y4)*0.5f;
x123 = (x12+x23)*0.5f;
y123 = (y12+y23)*0.5f;
dx = x4 - x1;
dy = y4 - y1;
d2 = nsvg__absf(((x2 - x4) * dy - (y2 - y4) * dx));
d3 = nsvg__absf(((x3 - x4) * dy - (y3 - y4) * dx));
if ((d2 + d3)*(d2 + d3) < r->tessTol * (dx*dx + dy*dy)) {
nsvg__addPathPoint(r, x4, y4, type);
return;
}
++level;
if (level > max_level) return;
x234 = (x23+x34)*0.5f;
y234 = (y23+y34)*0.5f;
x1234 = (x123+x234)*0.5f;
y1234 = (y123+y234)*0.5f;
nsvg__flattenCubicBez(r, x1,y1, x12,y12, x123,y123, x1234,y1234, level, 0);
nsvg__flattenCubicBez(r, x1234,y1234, x234,y234, x34,y34, x4,y4, level, type);
}
static void nsvg__flattenShape(NSVGrasterizer* r, NSVGshape* shape, float scale)
{
int i, j;
NSVGpath* path;
for (path = shape->paths; path != NULL; path = path->next) {
r->npoints = 0;
// Flatten path
nsvg__addPathPoint(r, path->pts[0]*scale, path->pts[1]*scale, 0);
for (i = 0; i < path->npts-1; i += 3) {
float* p = &path->pts[i*2];
nsvg__flattenCubicBez(r, p[0]*scale,p[1]*scale, p[2]*scale,p[3]*scale, p[4]*scale,p[5]*scale, p[6]*scale,p[7]*scale, 0, 0);
}
// Close path
nsvg__addPathPoint(r, path->pts[0]*scale, path->pts[1]*scale, 0);
// Build edges
for (i = 0, j = r->npoints-1; i < r->npoints; j = i++)
nsvg__addEdge(r, r->points[j].x, r->points[j].y, r->points[i].x, r->points[i].y);
}
}
enum NSVGpointFlags
{
NSVG_PT_CORNER = 0x01,
NSVG_PT_BEVEL = 0x02,
NSVG_PT_LEFT = 0x04
};
static void nsvg__initClosed(NSVGpoint* left, NSVGpoint* right, NSVGpoint* p0, NSVGpoint* p1, float lineWidth)
{
float w = lineWidth * 0.5f;
float dx = p1->x - p0->x;
float dy = p1->y - p0->y;
float len = nsvg__normalize(&dx, &dy);
float px = p0->x + dx*len*0.5f, py = p0->y + dy*len*0.5f;
float dlx = dy, dly = -dx;
float lx = px - dlx*w, ly = py - dly*w;
float rx = px + dlx*w, ry = py + dly*w;
left->x = lx; left->y = ly;
right->x = rx; right->y = ry;
}
static void nsvg__buttCap(NSVGrasterizer* r, NSVGpoint* left, NSVGpoint* right, NSVGpoint* p, float dx, float dy, float lineWidth, int connect)
{
float w = lineWidth * 0.5f;
float px = p->x, py = p->y;
float dlx = dy, dly = -dx;
float lx = px - dlx*w, ly = py - dly*w;
float rx = px + dlx*w, ry = py + dly*w;
nsvg__addEdge(r, lx, ly, rx, ry);
if (connect) {
nsvg__addEdge(r, left->x, left->y, lx, ly);
nsvg__addEdge(r, rx, ry, right->x, right->y);
}
left->x = lx; left->y = ly;
right->x = rx; right->y = ry;
}
static void nsvg__squareCap(NSVGrasterizer* r, NSVGpoint* left, NSVGpoint* right, NSVGpoint* p, float dx, float dy, float lineWidth, int connect)
{
float w = lineWidth * 0.5f;
float px = p->x - dx*w, py = p->y - dy*w;
float dlx = dy, dly = -dx;
float lx = px - dlx*w, ly = py - dly*w;
float rx = px + dlx*w, ry = py + dly*w;
nsvg__addEdge(r, lx, ly, rx, ry);
if (connect) {
nsvg__addEdge(r, left->x, left->y, lx, ly);
nsvg__addEdge(r, rx, ry, right->x, right->y);
}
left->x = lx; left->y = ly;
right->x = rx; right->y = ry;
}
#ifndef NSVG_PI
#define NSVG_PI (3.14159265358979323846264338327f)
#endif
static void nsvg__roundCap(NSVGrasterizer* r, NSVGpoint* left, NSVGpoint* right, NSVGpoint* p, float dx, float dy, float lineWidth, int ncap, int connect)
{
int i;
float w = lineWidth * 0.5f;
float px = p->x, py = p->y;
float dlx = dy, dly = -dx;
float lx = 0, ly = 0, rx = 0, ry = 0, prevx = 0, prevy = 0;
for (i = 0; i < ncap; i++) {
float a = (float)i/(float)(ncap-1)*NSVG_PI;
float ax = cosf(a) * w, ay = sinf(a) * w;
float x = px - dlx*ax - dx*ay;
float y = py - dly*ax - dy*ay;
if (i > 0)
nsvg__addEdge(r, prevx, prevy, x, y);
prevx = x;
prevy = y;
if (i == 0) {
lx = x; ly = y;
} else if (i == ncap-1) {
rx = x; ry = y;
}
}
if (connect) {
nsvg__addEdge(r, left->x, left->y, lx, ly);
nsvg__addEdge(r, rx, ry, right->x, right->y);
}
left->x = lx; left->y = ly;
right->x = rx; right->y = ry;
}
static void nsvg__bevelJoin(NSVGrasterizer* r, NSVGpoint* left, NSVGpoint* right, NSVGpoint* p0, NSVGpoint* p1, float lineWidth)
{
float w = lineWidth * 0.5f;
float dlx0 = p0->dy, dly0 = -p0->dx;
float dlx1 = p1->dy, dly1 = -p1->dx;
float lx0 = p1->x - (dlx0 * w), ly0 = p1->y - (dly0 * w);
float rx0 = p1->x + (dlx0 * w), ry0 = p1->y + (dly0 * w);
float lx1 = p1->x - (dlx1 * w), ly1 = p1->y - (dly1 * w);
float rx1 = p1->x + (dlx1 * w), ry1 = p1->y + (dly1 * w);
nsvg__addEdge(r, lx0, ly0, left->x, left->y);
nsvg__addEdge(r, lx1, ly1, lx0, ly0);
nsvg__addEdge(r, right->x, right->y, rx0, ry0);
nsvg__addEdge(r, rx0, ry0, rx1, ry1);
left->x = lx1; left->y = ly1;
right->x = rx1; right->y = ry1;
}
static void nsvg__miterJoin(NSVGrasterizer* r, NSVGpoint* left, NSVGpoint* right, NSVGpoint* p0, NSVGpoint* p1, float lineWidth)
{
float w = lineWidth * 0.5f;
float dlx0 = p0->dy, dly0 = -p0->dx;
float dlx1 = p1->dy, dly1 = -p1->dx;
float lx0, rx0, lx1, rx1;
float ly0, ry0, ly1, ry1;
if (p1->flags & NSVG_PT_LEFT) {
lx0 = lx1 = p1->x - p1->dmx * w;
ly0 = ly1 = p1->y - p1->dmy * w;
nsvg__addEdge(r, lx1, ly1, left->x, left->y);
rx0 = p1->x + (dlx0 * w);
ry0 = p1->y + (dly0 * w);
rx1 = p1->x + (dlx1 * w);
ry1 = p1->y + (dly1 * w);
nsvg__addEdge(r, right->x, right->y, rx0, ry0);
nsvg__addEdge(r, rx0, ry0, rx1, ry1);
} else {
lx0 = p1->x - (dlx0 * w);
ly0 = p1->y - (dly0 * w);
lx1 = p1->x - (dlx1 * w);
ly1 = p1->y - (dly1 * w);
nsvg__addEdge(r, lx0, ly0, left->x, left->y);
nsvg__addEdge(r, lx1, ly1, lx0, ly0);
rx0 = rx1 = p1->x + p1->dmx * w;
ry0 = ry1 = p1->y + p1->dmy * w;
nsvg__addEdge(r, right->x, right->y, rx1, ry1);
}
left->x = lx1; left->y = ly1;
right->x = rx1; right->y = ry1;
}
static void nsvg__roundJoin(NSVGrasterizer* r, NSVGpoint* left, NSVGpoint* right, NSVGpoint* p0, NSVGpoint* p1, float lineWidth, int ncap)
{
int i, n;
float w = lineWidth * 0.5f;
float dlx0 = p0->dy, dly0 = -p0->dx;
float dlx1 = p1->dy, dly1 = -p1->dx;
float a0 = atan2f(dly0, dlx0);
float a1 = atan2f(dly1, dlx1);
float da = a1 - a0;
float lx, ly, rx, ry;
if (da < NSVG_PI) da += NSVG_PI*2;
if (da > NSVG_PI) da -= NSVG_PI*2;
n = (int)ceilf((nsvg__absf(da) / NSVG_PI) * (float)ncap);
if (n < 2) n = 2;
if (n > ncap) n = ncap;
lx = left->x;
ly = left->y;
rx = right->x;
ry = right->y;
for (i = 0; i < n; i++) {
float u = (float)i/(float)(n-1);
float a = a0 + u*da;
float ax = cosf(a) * w, ay = sinf(a) * w;
float lx1 = p1->x - ax, ly1 = p1->y - ay;
float rx1 = p1->x + ax, ry1 = p1->y + ay;
nsvg__addEdge(r, lx1, ly1, lx, ly);
nsvg__addEdge(r, rx, ry, rx1, ry1);
lx = lx1; ly = ly1;
rx = rx1; ry = ry1;
}
left->x = lx; left->y = ly;
right->x = rx; right->y = ry;
}
static void nsvg__straightJoin(NSVGrasterizer* r, NSVGpoint* left, NSVGpoint* right, NSVGpoint* p1, float lineWidth)
{
float w = lineWidth * 0.5f;
float lx = p1->x - (p1->dmx * w), ly = p1->y - (p1->dmy * w);
float rx = p1->x + (p1->dmx * w), ry = p1->y + (p1->dmy * w);
nsvg__addEdge(r, lx, ly, left->x, left->y);
nsvg__addEdge(r, right->x, right->y, rx, ry);
left->x = lx; left->y = ly;
right->x = rx; right->y = ry;
}
static int nsvg__curveDivs(float r, float arc, float tol)
{
float da = acosf(r / (r + tol)) * 2.0f;
int divs = (int)ceilf(arc / da);
if (divs < 2) divs = 2;
return divs;
}
static void nsvg__expandStroke(NSVGrasterizer* r, NSVGpoint* points, int npoints, int closed, int lineJoin, int lineCap, float lineWidth)
{
int ncap = nsvg__curveDivs(lineWidth*0.5f, NSVG_PI, r->tessTol); // Calculate divisions per half circle.
NSVGpoint left = {0,0,0,0,0,0,0,0}, right = {0,0,0,0,0,0,0,0}, firstLeft = {0,0,0,0,0,0,0,0}, firstRight = {0,0,0,0,0,0,0,0};
NSVGpoint* p0, *p1;
int j, s, e;
// Build stroke edges
if (closed) {
// Looping
p0 = &points[npoints-1];
p1 = &points[0];
s = 0;
e = npoints;
} else {
// Add cap
p0 = &points[0];
p1 = &points[1];
s = 1;
e = npoints-1;
}
if (closed) {
nsvg__initClosed(&left, &right, p0, p1, lineWidth);
firstLeft = left;
firstRight = right;
} else {
// Add cap
float dx = p1->x - p0->x;
float dy = p1->y - p0->y;
nsvg__normalize(&dx, &dy);
if (lineCap == NSVG_CAP_BUTT)
nsvg__buttCap(r, &left, &right, p0, dx, dy, lineWidth, 0);
else if (lineCap == NSVG_CAP_SQUARE)
nsvg__squareCap(r, &left, &right, p0, dx, dy, lineWidth, 0);
else if (lineCap == NSVG_CAP_ROUND)
nsvg__roundCap(r, &left, &right, p0, dx, dy, lineWidth, ncap, 0);
}
for (j = s; j < e; ++j) {
if (p1->flags & NSVG_PT_CORNER) {
if (lineJoin == NSVG_JOIN_ROUND)
nsvg__roundJoin(r, &left, &right, p0, p1, lineWidth, ncap);
else if (lineJoin == NSVG_JOIN_BEVEL || (p1->flags & NSVG_PT_BEVEL))
nsvg__bevelJoin(r, &left, &right, p0, p1, lineWidth);
else
nsvg__miterJoin(r, &left, &right, p0, p1, lineWidth);
} else {
nsvg__straightJoin(r, &left, &right, p1, lineWidth);
}
p0 = p1++;
}
if (closed) {
// Loop it
nsvg__addEdge(r, firstLeft.x, firstLeft.y, left.x, left.y);
nsvg__addEdge(r, right.x, right.y, firstRight.x, firstRight.y);
} else {
// Add cap
float dx = p1->x - p0->x;
float dy = p1->y - p0->y;
nsvg__normalize(&dx, &dy);
if (lineCap == NSVG_CAP_BUTT)
nsvg__buttCap(r, &right, &left, p1, -dx, -dy, lineWidth, 1);
else if (lineCap == NSVG_CAP_SQUARE)
nsvg__squareCap(r, &right, &left, p1, -dx, -dy, lineWidth, 1);
else if (lineCap == NSVG_CAP_ROUND)
nsvg__roundCap(r, &right, &left, p1, -dx, -dy, lineWidth, ncap, 1);
}
}
static void nsvg__prepareStroke(NSVGrasterizer* r, float miterLimit, int lineJoin)
{
int i, j;
NSVGpoint* p0, *p1;
p0 = &r->points[r->npoints-1];
p1 = &r->points[0];
for (i = 0; i < r->npoints; i++) {
// Calculate segment direction and length
p0->dx = p1->x - p0->x;
p0->dy = p1->y - p0->y;
p0->len = nsvg__normalize(&p0->dx, &p0->dy);
// Advance
p0 = p1++;
}
// calculate joins
p0 = &r->points[r->npoints-1];
p1 = &r->points[0];
for (j = 0; j < r->npoints; j++) {
float dlx0, dly0, dlx1, dly1, dmr2, cross;
dlx0 = p0->dy;
dly0 = -p0->dx;
dlx1 = p1->dy;
dly1 = -p1->dx;
// Calculate extrusions
p1->dmx = (dlx0 + dlx1) * 0.5f;
p1->dmy = (dly0 + dly1) * 0.5f;
dmr2 = p1->dmx*p1->dmx + p1->dmy*p1->dmy;
if (dmr2 > 0.000001f) {
float s2 = 1.0f / dmr2;
if (s2 > 600.0f) {
s2 = 600.0f;
}
p1->dmx *= s2;
p1->dmy *= s2;
}
// Clear flags, but keep the corner.
p1->flags = (p1->flags & NSVG_PT_CORNER) ? NSVG_PT_CORNER : 0;
// Keep track of left turns.
cross = p1->dx * p0->dy - p0->dx * p1->dy;
if (cross > 0.0f)
p1->flags |= NSVG_PT_LEFT;
// Check to see if the corner needs to be beveled.
if (p1->flags & NSVG_PT_CORNER) {
if ((dmr2 * miterLimit*miterLimit) < 1.0f || lineJoin == NSVG_JOIN_BEVEL || lineJoin == NSVG_JOIN_ROUND) {
p1->flags |= NSVG_PT_BEVEL;
}
}
p0 = p1++;
}
}
static void nsvg__flattenShapeStroke(NSVGrasterizer* r, NSVGshape* shape, float scale)
{
int i, j, closed;
NSVGpath* path;
NSVGpoint* p0, *p1;
float miterLimit = shape->miterLimit;
int lineJoin = shape->strokeLineJoin;
int lineCap = shape->strokeLineCap;
float lineWidth = shape->strokeWidth * scale;
for (path = shape->paths; path != NULL; path = path->next) {
// Flatten path
r->npoints = 0;
nsvg__addPathPoint(r, path->pts[0]*scale, path->pts[1]*scale, NSVG_PT_CORNER);
for (i = 0; i < path->npts-1; i += 3) {
float* p = &path->pts[i*2];
nsvg__flattenCubicBez(r, p[0]*scale,p[1]*scale, p[2]*scale,p[3]*scale, p[4]*scale,p[5]*scale, p[6]*scale,p[7]*scale, 0, NSVG_PT_CORNER);
}
if (r->npoints < 2)
continue;
closed = path->closed;
// If the first and last points are the same, remove the last, mark as closed path.
p0 = &r->points[r->npoints-1];
p1 = &r->points[0];
if (nsvg__ptEquals(p0->x,p0->y, p1->x,p1->y, r->distTol)) {
r->npoints--;
p0 = &r->points[r->npoints-1];
closed = 1;
}
if (shape->strokeDashCount > 0) {
int idash = 0, dashState = 1;
float totalDist = 0, dashLen, allDashLen, dashOffset;
NSVGpoint cur;
if (closed)
nsvg__appendPathPoint(r, r->points[0]);
// Duplicate points -> points2.
nsvg__duplicatePoints(r);
r->npoints = 0;
cur = r->points2[0];
nsvg__appendPathPoint(r, cur);
// Figure out dash offset.
allDashLen = 0;
for (j = 0; j < shape->strokeDashCount; j++)
allDashLen += shape->strokeDashArray[j];
if (shape->strokeDashCount & 1)
allDashLen *= 2.0f;
// Find location inside pattern
dashOffset = fmodf(shape->strokeDashOffset, allDashLen);
if (dashOffset < 0.0f)
dashOffset += allDashLen;
while (dashOffset > shape->strokeDashArray[idash]) {
dashOffset -= shape->strokeDashArray[idash];
idash = (idash + 1) % shape->strokeDashCount;
}
dashLen = (shape->strokeDashArray[idash] - dashOffset) * scale;
for (j = 1; j < r->npoints2; ) {
float dx = r->points2[j].x - cur.x;
float dy = r->points2[j].y - cur.y;
float dist = sqrtf(dx*dx + dy*dy);
if ((totalDist + dist) > dashLen) {
// Calculate intermediate point
float d = (dashLen - totalDist) / dist;
float x = cur.x + dx * d;
float y = cur.y + dy * d;
nsvg__addPathPoint(r, x, y, NSVG_PT_CORNER);
// Stroke
if (r->npoints > 1 && dashState) {
nsvg__prepareStroke(r, miterLimit, lineJoin);
nsvg__expandStroke(r, r->points, r->npoints, 0, lineJoin, lineCap, lineWidth);
}
// Advance dash pattern
dashState = !dashState;
idash = (idash+1) % shape->strokeDashCount;
dashLen = shape->strokeDashArray[idash] * scale;
// Restart
cur.x = x;
cur.y = y;
cur.flags = NSVG_PT_CORNER;
totalDist = 0.0f;
r->npoints = 0;
nsvg__appendPathPoint(r, cur);
} else {
totalDist += dist;
cur = r->points2[j];
nsvg__appendPathPoint(r, cur);
j++;
}
}
// Stroke any leftover path
if (r->npoints > 1 && dashState)
nsvg__expandStroke(r, r->points, r->npoints, 0, lineJoin, lineCap, lineWidth);
} else {
nsvg__prepareStroke(r, miterLimit, lineJoin);
nsvg__expandStroke(r, r->points, r->npoints, closed, lineJoin, lineCap, lineWidth);
}
}
}
static int SDLCALL
nsvg__cmpEdge(const void *p, const void *q)
{
const NSVGedge* a = (const NSVGedge*)p;
const NSVGedge* b = (const NSVGedge*)q;
if (a->y0 < b->y0) return -1;
if (a->y0 > b->y0) return 1;
return 0;
}
static NSVGactiveEdge* nsvg__addActive(NSVGrasterizer* r, NSVGedge* e, float startPoint)
{
NSVGactiveEdge* z;
float dxdy;
if (r->freelist != NULL) {
// Restore from freelist.
z = r->freelist;
r->freelist = z->next;
} else {
// Alloc new edge.
z = (NSVGactiveEdge*)nsvg__alloc(r, sizeof(NSVGactiveEdge));
if (z == NULL) return NULL;
}
dxdy = (e->x1 - e->x0) / (e->y1 - e->y0);
// STBTT_assert(e->y0 <= start_point);
// round dx down to avoid going too far
if (dxdy < 0)
z->dx = (int)(-floorf(NSVG__FIX * -dxdy));
else
z->dx = (int)floorf(NSVG__FIX * dxdy);
z->x = (int)floorf(NSVG__FIX * (e->x0 + dxdy * (startPoint - e->y0)));
// z->x -= off_x * FIX;
z->ey = e->y1;
z->next = 0;
z->dir = e->dir;
return z;
}
static void nsvg__freeActive(NSVGrasterizer* r, NSVGactiveEdge* z)
{
z->next = r->freelist;
r->freelist = z;
}
static void nsvg__fillScanline(unsigned char* scanline, int len, int x0, int x1, int maxWeight, int* xmin, int* xmax)
{
int i = x0 >> NSVG__FIXSHIFT;
int j = x1 >> NSVG__FIXSHIFT;
if (i < *xmin) *xmin = i;
if (j > *xmax) *xmax = j;
if (i < len && j >= 0) {
if (i == j) {
// x0,x1 are the same pixel, so compute combined coverage
scanline[i] = (unsigned char)(scanline[i] + ((x1 - x0) * maxWeight >> NSVG__FIXSHIFT));
} else {
if (i >= 0) // add antialiasing for x0
scanline[i] = (unsigned char)(scanline[i] + (((NSVG__FIX - (x0 & NSVG__FIXMASK)) * maxWeight) >> NSVG__FIXSHIFT));
else
i = -1; // clip
if (j < len) // add antialiasing for x1
scanline[j] = (unsigned char)(scanline[j] + (((x1 & NSVG__FIXMASK) * maxWeight) >> NSVG__FIXSHIFT));
else
j = len; // clip
for (++i; i < j; ++i) // fill pixels between x0 and x1
scanline[i] = (unsigned char)(scanline[i] + maxWeight);
}
}
}
// note: this routine clips fills that extend off the edges... ideally this
// wouldn't happen, but it could happen if the truetype glyph bounding boxes
// are wrong, or if the user supplies a too-small bitmap
static void nsvg__fillActiveEdges(unsigned char* scanline, int len, NSVGactiveEdge* e, int maxWeight, int* xmin, int* xmax, char fillRule)
{
// non-zero winding fill
int x0 = 0, w = 0;
if (fillRule == NSVG_FILLRULE_NONZERO) {
// Non-zero
while (e != NULL) {
if (w == 0) {
// if we're currently at zero, we need to record the edge start point
x0 = e->x; w += e->dir;
} else {
int x1 = e->x; w += e->dir;
// if we went to zero, we need to draw
if (w == 0)
nsvg__fillScanline(scanline, len, x0, x1, maxWeight, xmin, xmax);
}
e = e->next;
}
} else if (fillRule == NSVG_FILLRULE_EVENODD) {
// Even-odd
while (e != NULL) {
if (w == 0) {
// if we're currently at zero, we need to record the edge start point
x0 = e->x; w = 1;
} else {
int x1 = e->x; w = 0;
nsvg__fillScanline(scanline, len, x0, x1, maxWeight, xmin, xmax);
}
e = e->next;
}
}
}
static float nsvg__clampf(float a, float mn, float mx) { return a < mn ? mn : (a > mx ? mx : a); }
static unsigned int nsvg__RGBA(unsigned char r, unsigned char g, unsigned char b, unsigned char a)
{
return ((unsigned int)r) | ((unsigned int)g << 8) | ((unsigned int)b << 16) | ((unsigned int)a << 24);
}
static unsigned int nsvg__lerpRGBA(unsigned int c0, unsigned int c1, float u)
{
int iu = (int)(nsvg__clampf(u, 0.0f, 1.0f) * 256.0f);
int r = (((c0) & 0xff)*(256-iu) + (((c1) & 0xff)*iu)) >> 8;
int g = (((c0>>8) & 0xff)*(256-iu) + (((c1>>8) & 0xff)*iu)) >> 8;
int b = (((c0>>16) & 0xff)*(256-iu) + (((c1>>16) & 0xff)*iu)) >> 8;
int a = (((c0>>24) & 0xff)*(256-iu) + (((c1>>24) & 0xff)*iu)) >> 8;
return nsvg__RGBA((unsigned char)r, (unsigned char)g, (unsigned char)b, (unsigned char)a);
}
static unsigned int nsvg__applyOpacity(unsigned int c, float u)
{
int iu = (int)(nsvg__clampf(u, 0.0f, 1.0f) * 256.0f);
int r = (c) & 0xff;
int g = (c>>8) & 0xff;
int b = (c>>16) & 0xff;
int a = (((c>>24) & 0xff)*iu) >> 8;
return nsvg__RGBA((unsigned char)r, (unsigned char)g, (unsigned char)b, (unsigned char)a);
}
static int nsvg__div255(int x)
{
return ((x+1) * 257) >> 16;
}
static void nsvg__scanlineSolid(unsigned char* dst, int count, unsigned char* cover, int x, int y,
float tx, float ty, float scale, NSVGcachedPaint* cache)
{
if (cache->type == NSVG_PAINT_COLOR) {