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0,0 → 1,102 |
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dojox.gfx |
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Version 1.100 |
Release date: 08/01/2006 |
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Project state: |
beta |
HTMLCanvas renderer: experimental |
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Credits |
Eugene Lazutkin (eugene.lazutkin@gmail.com) |
Kun Xi (bookstack@gmail.com) |
Chris Mitchell (ccmitchellusa@gmail.com) HTML Canvas |
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Project description |
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Implementation of simple portable 2D graphics library. |
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Dependencies: |
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Dojo Core |
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Documentation |
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Currently it can be found here: http://docs.google.com/Doc?id=d764479_1hnb2tn |
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HTMLCanvas Renderer Status |
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To use canvas rendering, insert 'canvas' at the beginning of the gfxRenderers list in your |
djConfig, for example: |
<script type="text/javascript" src="../../../dojo/dojo.js" |
djConfig="parseOnLoad: true, gfxRenderer: 'canvas,svg,silverlight,vml'"></script> |
canvas currently will only render on non-IE browsers (see dojox/gfx.js for where the renderer is loaded); |
although it should be possible to use an IE canvas implementation (like Google's); however, it will be very slow. |
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The following tests can be made to work with HTML Canvas with minor testcase modification: |
dojox/gfx/tests |
test_gfx.html-Bugs #1 |
test_arc.html |
test_bezier.html |
test_pattern.html |
test_gradient.html |
test_linearGradient.html |
test_image1.html - Limitation #3 |
test_transform.html - Bug #1 |
test_poly.html - Bug #1 |
dojox/gfx/demos |
butterfly.html - Bug #1 |
lion.html - Bug #1 |
tiger.html - Bug #1 |
circles.html - No event processing yet :( |
creator.html |
dojox/chart |
test_pie2d.html - Dojo Charts on iPhone anyone? :) |
test_chart2d.html - |
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// To make charts work, the following line needs to be added to the end of the |
// Chart2D.js render() method (prior to return) |
if(this.surface.render){this.surface.render()}; |
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Known Limitations: |
1) event handling- plan is to capture all events at canvas, perform intersect/hit |
tests (not implemented) against scene graph, then propogate event to top-most |
intersected shape. HtmlCanvas shape need intersectsStroke and intersectsBounds, |
and intersects (region). |
2) SVG and VML are "live" scene graphs; eg. any state change to objects in the |
scene automatically get rendered in next engine render pass. For canvas, it's |
procedural, and current implementation requires application to call surface.render() |
whenever scene needs to be updated. Plan is to do dirty region checking based |
on bounding boxes (currently not properly computed), and track dirty areas anytime |
state changes (invalidate) separate from render phase. |
Add the following call where changes to the scene graph are complete and you want to |
render: |
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if (surface.render){surface.render();} |
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4) Text/Text Paths - Text shape is implemented using DIV overlays. Many text styles are not |
applied, and outline/fills are not possible. This is due to limitations in Canvas spec. |
Firefox 3.0 has proprietary text functions that we could test for and use once FF3 is out. |
No luck on Safari. |
3) No Image skewing - Limitation of Canvas |
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Known Bugs: |
1) Matrix xformations (applied from root to shape leaf nodes) not quite right--but very close. |
Canvas does not have a built in transformation function that allows skewing. Need to |
track skew matrix with Shape, and perform other trans/rot/scale transformations without |
using canvas transform functions. |
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Installation instructions |
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Grab the following from the Dojo SVN Repository: |
http://svn.dojotoolkit.org/var/src/dojo/dojox/trunk/gfx.js |
http://svn.dojotoolkit.org/var/src/dojo/dojox/trunk/gfx/* |
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Install into the following directory structure: |
/dojox/gfx/ |
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...which should be at the same level as your Dojo checkout. |
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