This commit adds full support for a new OpenSeaDragon(OSD) feature - Mirror/Flip.
In order to fully support this new feature, the following OSD objects had to be modified:
- drawer.js:
- navigator
- openseadragon
- strings
- tiledImage
- viewer
Additionally, a new flip button was created (similar to the existing ones).
Flip Logic
Whenever the state is flip button is pressed, flip state is toogled, inverting all the controls and displays (the rotation direction is inverted as well).
This means that all viewer coordinates (including user inputs) must me inverted too.
Summary of modifications
- drawer.js: modified _offsetForRotation to invert rotation angle on flipped state. Added a _flip method to scale/mirror canvas context.
- navigator.js: adds full flip support and inverts nagivator inputs.
- openseadragon.js: new buttons, flip state variable and showFlipControl variable.
- strings.js: flip tool help tips.
- tiledImage.js: flips the actual drawing canvas.
- viewer.js: Added keyboardshortcuts to rotate 90degrees (r/R) and flip image (f/F). flip button state is stored here and flip order is set.
The flipped state is stored on viewer object.
This is an option for different applications or user preferences:
If zoomToRefPoint in a gesture setting is true (default), the zoom is
centered at the pointer position. Otherwise, the zoom is centered at the
canvas center.
If there are multiple tiled images as overlay, it might be important to
see how they are loaded. Different colors in the debug mode for the
different tiledImages visualize that. DebugGridColors have to be given
as a sting array with a color for each tiledImage. However, shorter
arrays will be recycled without error. Also, single strings are treated
as single entry arrays, for backwards compatibility.
html <canvas> is used to process multiple tiledImages to blend
is a specific way.
(special handling,
when compositeOperation is 'source-over' and opacity is 1,
useSketch is false, otherwise useSketch is true
)
Valid values are 'source-atop', 'source-in', 'source-out',
'destination-over', 'destination-atop', 'destination-in',
'destination-out', 'lighter', 'copy' or 'xor'
http://www.w3schools.com/tags/canvas_globalcompositeoperation.asp
