static void
fz_add_line_stroke(struct sctx *s, fz_point a, fz_point b)
{
float dx = b.x - a.x;
float dy = b.y - a.y;
float scale = s->linewidth / sqrtf(dx * dx + dy * dy);
float dlx = dy * scale;
float dly = -dx * scale;
fz_add_line(s, a.x - dlx, a.y - dly, b.x - dlx, b.y - dly);
fz_add_line(s, b.x + dlx, b.y + dly, a.x + dlx, a.y + dly);
}
static void
fz_add_line_cap(struct sctx *s, fz_point a, fz_point b, fz_linecap linecap)
{
float flatness = s->flatness;
float linewidth = s->linewidth;
float dx = b.x - a.x;
float dy = b.y - a.y;
float scale = linewidth / sqrtf(dx * dx + dy * dy);
float dlx = dy * scale;
float dly = -dx * scale;
if (linecap == FZ_LINECAP_BUTT)
fz_add_line(s, b.x - dlx, b.y - dly, b.x + dlx, b.y + dly);
if (linecap == FZ_LINECAP_ROUND)
{
int i;
int n = ceilf((float)M_PI / (2.0f * (float)M_SQRT2 * sqrtf(flatness / linewidth)));
float ox = b.x - dlx;
float oy = b.y - dly;
for (i = 1; i < n; i++)
{
float theta = (float)M_PI * i / n;
float cth = cosf(theta);
float sth = sinf(theta);
float nx = b.x - dlx * cth - dly * sth;
float ny = b.y - dly * cth + dlx * sth;
fz_add_line(s, ox, oy, nx, ny);
ox = nx;
oy = ny;
}
fz_add_line(s, ox, oy, b.x + dlx, b.y + dly);
}
if (linecap == FZ_LINECAP_SQUARE)
{
fz_add_line(s, b.x - dlx, b.y - dly,
b.x - dlx - dly, b.y - dly + dlx);
fz_add_line(s, b.x - dlx - dly, b.y - dly + dlx,
b.x + dlx - dly, b.y + dly + dlx);
fz_add_line(s, b.x + dlx - dly, b.y + dly + dlx,
b.x + dlx, b.y + dly);
}
if (linecap == FZ_LINECAP_TRIANGLE)
{
float mx = -dly;
float my = dlx;
fz_add_line(s, b.x - dlx, b.y - dly, b.x + mx, b.y + my);
fz_add_line(s, b.x + mx, b.y + my, b.x + dlx, b.y + dly);
}
}
static void
fz_add_arc(struct sctx *s,
float xc, float yc,
float x0, float y0,
float x1, float y1)
{
float th0, th1, r;
float theta;
float ox, oy, nx, ny;
int n, i;
r = fabsf(s->linewidth);
theta = 2 * (float)M_SQRT2 * sqrtf(s->flatness / r);
th0 = atan2f(y0, x0);
th1 = atan2f(y1, x1);
if (r > 0)
{
if (th0 < th1)
th0 += (float)M_PI * 2;
n = ceilf((th0 - th1) / theta);
}
else
{
if (th1 < th0)
th1 += (float)M_PI * 2;
n = ceilf((th1 - th0) / theta);
}
ox = x0;
oy = y0;
for (i = 1; i < n; i++)
{
theta = th0 + (th1 - th0) * i / n;
nx = cosf(theta) * r;
ny = sinf(theta) * r;
fz_add_line(s, xc + ox, yc + oy, xc + nx, yc + ny);
ox = nx;
oy = ny;
}
fz_add_line(s, xc + ox, yc + oy, xc + x1, yc + y1);
}
static void
fz_add_line_dot(struct sctx *s, fz_point a)
{
float flatness = s->flatness;
float linewidth = s->linewidth;
int n = ceilf((float)M_PI / ((float)M_SQRT2 * sqrtf(flatness / linewidth)));
float ox = a.x - linewidth;
float oy = a.y;
int i;
for (i = 1; i < n; i++)
{
float theta = (float)M_PI * 2 * i / n;
float cth = cosf(theta);
float sth = sinf(theta);
float nx = a.x - cth * linewidth;
float ny = a.y + sth * linewidth;
fz_add_line(s, ox, oy, nx, ny);
ox = nx;
oy = ny;
}
fz_add_line(s, ox, oy, a.x - linewidth, a.y);
}
static void
fz_add_line_join(struct sctx *s, fz_point a, fz_point b, fz_point c, int join_under)
{
float miterlimit = s->miterlimit;
float linewidth = s->linewidth;
fz_linejoin linejoin = s->linejoin;
float dx0, dy0;
float dx1, dy1;
float dlx0, dly0;
float dlx1, dly1;
float dmx, dmy;
float dmr2;
float scale;
float cross;
float len0, len1;
dx0 = b.x - a.x;
dy0 = b.y - a.y;
dx1 = c.x - b.x;
dy1 = c.y - b.y;
cross = dx1 * dy0 - dx0 * dy1;
/* Ensure that cross >= 0 */
if (cross < 0)
{
float tmp;
tmp = dx1; dx1 = -dx0; dx0 = -tmp;
tmp = dy1; dy1 = -dy0; dy0 = -tmp;
cross = -cross;
}
len0 = dx0 * dx0 + dy0 * dy0;
if (len0 < FLT_EPSILON)
linejoin = FZ_LINEJOIN_BEVEL;
len1 = dx1 * dx1 + dy1 * dy1;
if (len1 < FLT_EPSILON)
linejoin = FZ_LINEJOIN_BEVEL;
scale = linewidth / sqrtf(len0);
dlx0 = dy0 * scale;
dly0 = -dx0 * scale;
scale = linewidth / sqrtf(len1);
dlx1 = dy1 * scale;
dly1 = -dx1 * scale;
dmx = (dlx0 + dlx1) * 0.5f;
dmy = (dly0 + dly1) * 0.5f;
dmr2 = dmx * dmx + dmy * dmy;
if (cross * cross < FLT_EPSILON && dx0 * dx1 + dy0 * dy1 >= 0)
linejoin = FZ_LINEJOIN_BEVEL;
if (join_under)
{
fz_add_line(s, b.x + dlx1, b.y + dly1, b.x + dlx0, b.y + dly0);
}
else
{
fz_add_line(s, b.x + dlx1, b.y + dly1, b.x, b.y);
fz_add_line(s, b.x, b.y, b.x + dlx0, b.y + dly0);
}
/* XPS miter joins are clipped at miterlength, rather than simply
* being converted to bevelled joins. */
if (linejoin == FZ_LINEJOIN_MITER_XPS)
{
if (cross == 0)
linejoin = FZ_LINEJOIN_BEVEL;
else if (dmr2 * miterlimit * miterlimit >= linewidth * linewidth)
linejoin = FZ_LINEJOIN_MITER;
else
{
float k, t0x, t0y, t1x, t1y;
scale = linewidth * linewidth / dmr2;
dmx *= scale;
dmy *= scale;
k = (scale - linewidth * miterlimit / sqrtf(dmr2)) / (scale - 1);
t0x = b.x - dmx + k * (dmx - dlx0);
t0y = b.y - dmy + k * (dmy - dly0);
t1x = b.x - dmx + k * (dmx - dlx1);
t1y = b.y - dmy + k * (dmy - dly1);
fz_add_line(s, b.x - dlx0, b.y - dly0, t0x, t0y);
fz_add_line(s, t0x, t0y, t1x, t1y);
fz_add_line(s, t1x, t1y, b.x - dlx1, b.y - dly1);
}
}
else if (linejoin == FZ_LINEJOIN_MITER)
if (dmr2 * miterlimit * miterlimit < linewidth * linewidth)
linejoin = FZ_LINEJOIN_BEVEL;
if (linejoin == FZ_LINEJOIN_MITER)
{
scale = linewidth * linewidth / dmr2;
dmx *= scale;
dmy *= scale;
fz_add_line(s, b.x - dlx0, b.y - dly0, b.x - dmx, b.y - dmy);
fz_add_line(s, b.x - dmx, b.y - dmy, b.x - dlx1, b.y - dly1);
}
if (linejoin == FZ_LINEJOIN_BEVEL)
{
fz_add_line(s, b.x - dlx0, b.y - dly0, b.x - dlx1, b.y - dly1);
}
if (linejoin == FZ_LINEJOIN_ROUND)
{
fz_add_arc(s, b.x, b.y, -dlx0, -dly0, -dlx1, -dly1);
}
}
static void
fz_add_line_join(struct sctx *s, fz_point a, fz_point b, fz_point c)
{
float miterlimit = s->miterlimit;
float linewidth = s->linewidth;
int linejoin = s->linejoin;
float dx0, dy0;
float dx1, dy1;
float dlx0, dly0;
float dlx1, dly1;
float dmx, dmy;
float dmr2;
float scale;
float cross;
dx0 = b.x - a.x;
dy0 = b.y - a.y;
dx1 = c.x - b.x;
dy1 = c.y - b.y;
if (dx0 * dx0 + dy0 * dy0 < FLT_EPSILON)
linejoin = BEVEL;
if (dx1 * dx1 + dy1 * dy1 < FLT_EPSILON)
linejoin = BEVEL;
scale = linewidth / sqrtf(dx0 * dx0 + dy0 * dy0);
dlx0 = dy0 * scale;
dly0 = -dx0 * scale;
scale = linewidth / sqrtf(dx1 * dx1 + dy1 * dy1);
dlx1 = dy1 * scale;
dly1 = -dx1 * scale;
cross = dx1 * dy0 - dx0 * dy1;
dmx = (dlx0 + dlx1) * 0.5f;
dmy = (dly0 + dly1) * 0.5f;
dmr2 = dmx * dmx + dmy * dmy;
if (cross * cross < FLT_EPSILON && dx0 * dx1 + dy0 * dy1 >= 0)
linejoin = BEVEL;
if (linejoin == MITER)
if (dmr2 * miterlimit * miterlimit < linewidth * linewidth)
linejoin = BEVEL;
if (linejoin == BEVEL)
{
fz_add_line(s, b.x - dlx0, b.y - dly0, b.x - dlx1, b.y - dly1);
fz_add_line(s, b.x + dlx1, b.y + dly1, b.x + dlx0, b.y + dly0);
}
if (linejoin == MITER)
{
scale = linewidth * linewidth / dmr2;
dmx *= scale;
dmy *= scale;
if (cross < 0)
{
fz_add_line(s, b.x - dlx0, b.y - dly0, b.x - dlx1, b.y - dly1);
fz_add_line(s, b.x + dlx1, b.y + dly1, b.x + dmx, b.y + dmy);
fz_add_line(s, b.x + dmx, b.y + dmy, b.x + dlx0, b.y + dly0);
}
else
{
fz_add_line(s, b.x + dlx1, b.y + dly1, b.x + dlx0, b.y + dly0);
fz_add_line(s, b.x - dlx0, b.y - dly0, b.x - dmx, b.y - dmy);
fz_add_line(s, b.x - dmx, b.y - dmy, b.x - dlx1, b.y - dly1);
}
}
if (linejoin == ROUND)
{
if (cross < 0)
{
fz_add_line(s, b.x - dlx0, b.y - dly0, b.x - dlx1, b.y - dly1);
fz_add_arc(s, b.x, b.y, dlx1, dly1, dlx0, dly0);
}
else
{
fz_add_line(s, b.x + dlx1, b.y + dly1, b.x + dlx0, b.y + dly0);
fz_add_arc(s, b.x, b.y, -dlx0, -dly0, -dlx1, -dly1);
}
}
}
