[canviz] r477 committed - fix Y-coordinate of simple strings when drawing text to the canvas

[can...@googlecode.com]

Revision: 477
Author: ryandesign.com
Date: Thu Sep 5 03:26:37 2013 UTC
Log: fix Y-coordinate of simple strings when drawing text to the canvas

http://code.google.com/p/canviz/source/detail?r=477

Modified:
/canviz/trunk/src/Entity.js

=======================================
--- /canviz/trunk/src/Entity.js Mon Aug 26 21:10:36 2013 UTC
+++ /canviz/trunk/src/Entity.js Thu Sep 5 03:26:37 2013 UTC
@@ -148,6 +148,14 @@
str = tokenizer.takeString();

if (!/^\s*$/.test(str)) {
+ // The Y-coordinate of text operations in xdot neglects to
take
+ // into account the yoffset_centerline. The error
for "simple"
+ // strings is -0.2 * fontSize and -1 for complex ones;
+ // unfortunately xdot does not tell us whether a string is
+ // simple or complex. We adjust for the more common simple
+ // case, though this causes complex strings to look worse.
+ // http://www.graphviz.org/mantisbt/view.php?id=2333
+ var yError = -0.2 * fontSize;
switch (this.canviz.textMode) {
case 'canvas':
ctx.save();
@@ -157,9 +165,7 @@
ctx.font = fontSize + 'px ' + fontFamily;
// xdot uses pen color for text, but canvas uses fill
color
ctx.fillStyle = ctx.strokeStyle;
- //var metrics = ctx.measureText(str);
- //console.log(str, metrics);
- ctx.fillText(str, 0, 0); // TODO: the Y-coordinate is
even less correct than when using the DOM
+ ctx.fillText(str, 0, yError);
ctx.restore();
break;
case 'dom':