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Fixes type3 glyph compilation for bitpacked mask

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This commit is contained in:
Yury Delendik 2014-01-13 21:21:03 -06:00
parent 3f533a1cb0
commit 1991efe4f0
1 changed files with 24 additions and 12 deletions
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36
src/display/canvas.js
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@ -191,6 +191,18 @@ function compileType3Glyph(imgData) {
var points = new Uint8Array(width1 * (height + 1));
var POINT_TYPES =
new Uint8Array([0, 2, 4, 0, 1, 0, 5, 4, 8, 10, 0, 8, 0, 2, 1, 0]);
// decodes bit-packed mask data
var lineSize = (width + 7) & ~7, data0 = imgData.data;
var data = new Uint8Array(lineSize * height), pos = 0, ii;
for (i = 0, ii = data0.length; i < ii; i++) {
var mask = 128, elem = data0[i];
while (mask > 0) {
data[pos++] = (elem & mask) ? 0 : 255;
mask >>= 1;
}
}
// finding iteresting points: every point is located between mask pixels,
// so there will be points of the (width + 1)x(height + 1) grid. Every point
// will have flags assigned based on neighboring mask pixels:
@ -201,24 +213,25 @@ function compileType3Glyph(imgData) {
// - outside corners: 1, 2, 4, 8;
// - inside corners: 7, 11, 13, 14;
// - and, intersections: 5, 10.
var pos = 3, data = imgData.data, lineSize = width * 4, count = 0;
if (data[3] !== 0) {
var count = 0;
pos = 0;
if (data[pos] !== 0) {
points[0] = 1;
++count;
}
for (j = 1; j < width; j++) {
if (data[pos] !== data[pos + 4]) {
if (data[pos] !== data[pos + 1]) {
points[j] = data[pos] ? 2 : 1;
++count;
}
pos += 4;
pos++;
}
if (data[pos] !== 0) {
points[j] = 2;
++count;
}
pos += 4;
for (i = 1; i < height; i++) {
pos = i * lineSize;
j0 = i * width1;
if (data[pos - lineSize] !== data[pos]) {
points[j0] = data[pos] ? 1 : 8;
@ -228,37 +241,36 @@ function compileType3Glyph(imgData) {
// array (in order 8-1-2-4, so we can use '>>2' to shift the column).
var sum = (data[pos] ? 4 : 0) + (data[pos - lineSize] ? 8 : 0);
for (j = 1; j < width; j++) {
sum = (sum >> 2) + (data[pos + 4] ? 4 : 0) +
(data[pos - lineSize + 4] ? 8 : 0);
sum = (sum >> 2) + (data[pos + 1] ? 4 : 0) +
(data[pos - lineSize + 1] ? 8 : 0);
if (POINT_TYPES[sum]) {
points[j0 + j] = POINT_TYPES[sum];
++count;
}
pos += 4;
pos++;
}
if (data[pos - lineSize] !== data[pos]) {
points[j0 + j] = data[pos] ? 2 : 4;
++count;
}
pos += 4;
if (count > POINT_TO_PROCESS_LIMIT) {
return null;
}
}
pos -= lineSize;
pos = lineSize * (height - 1);
j0 = i * width1;
if (data[pos] !== 0) {
points[j0] = 8;
++count;
}
for (j = 1; j < width; j++) {
if (data[pos] !== data[pos + 4]) {
if (data[pos] !== data[pos + 1]) {
points[j0 + j] = data[pos] ? 4 : 8;
++count;
}
pos += 4;
pos++;
}
if (data[pos] !== 0) {
points[j0 + j] = 4;