xcfreader v0.0.6
xcfreader
Parses files generated by Gimp (.xcf)
xcfreader can
- Parse a gimp file.
- Provide image width and height information.
- Provide layer information including width, height, x offset in the main image, y offset from the main image.
- Render each layer using an image generator
- Flatten the file using an image generator
xcfreader only supports
- rgb and rgba file formats.
- raster images
xcfreader todo
- support text layers.
- support indexed images
- support grayscale images
- support paths
- perform proper layer flattening. (Currently the pixel is over written by the layer)
Installation
Install this module with the following command:
npm install xcfreader
Add the module to your package.json dependencies:
npm install --save xcfreader
Add the module to your package.json dev-dependencies
npm install --save-dev xcfreader
Usage
Require the module
import XCFReader from 'xcfreader';
Read a file
XCFReader.parseFile('./myimage.xcf, function(err, xcfReader){
if (err) throw err;
// Get width and height
console.log(xcfReader.width);
console.log(xcfReader.height);
// Get the number of layers
console.log(xcfReader.layers.length);
// Get the width and height of the top layer
console.log(xcfreader.layers[0].width);
console.log(xcfreader.layers[0].height);
// Flattern an image
var xcf = new XCFImage() // should call your Image class.
xcf.fill({red:0, green:0, blue: 0, alpha: 255}); // You need to set up the image with the default background for the image.
// Layer[0] is the top most layer whilst layer[layer.length-1] is the lowest level
// So we need to apply from the end of the layer array.
var numLayers = xcfreader.layers.length;
for(var loop = numLayers -1; loop >=0; loop -=1){
xcfreader.layers[loop].makeImage(xcf,true); // Put the current layer on to the image.
}
xcf.save('myImage.png');
});
Saving an Image If you want to save either the layer images or the whole image you need to provide a class instance that implements the folling interface
XCFImageInterface {
//set a pixel at a given position.
// @param x the x co-ordinate to set (Can be outside of the image);
// @param y the y co-ordinate to set (Can be outside of the image);
// @param colour { red:<0-255> , green:<0-255> , blue: <0-255>, alpha: <o-255>} // alpha is only include if the layer includes transparancy informatin
setAt(int: x, int: y, obj: colour);
// get the pixel at a given position ( Not currently used, but will in the future to perform flattening)
// @param x the x co-ordinate to set (Can be outside of the image);
// @param y the y co-ordinate to set (Can be outside of the image);
// @return colour { red:<0-255> , green:<0-255> , blue: <0-255>, alpha: <o-255>} // alpha is only include if the layer includes transparancy informatin
obj: colour getAt(int: x, int: y);
}
Class XCFParser
Static methods
parseImage(string: filename, function: callback)
filename
the file to parse
callback
function(Error:err , GimpParser: xcfReader) called when the parsing has completed.
Methods
createImage(XCFImage image)
image
instance of a class derived from the above interface.
Returns the image with all visible layers flattened. If image
if null then an XCFImage is created of the correct width and height
Properties
width
The width of the image
height
The height of the image
layers
An array of GimpLayer objects
Class GimpLayer
Methods
makeImage(XCFImage: image , boolean: useOffset)
image
instance of a class derived from the above interface.
useOffset
(defaults to false) wether to use the layer offset.
Returns:
image | useOffset | layer is visible | Action |
---|---|---|---|
null | true / false | false | returns null |
null | true | true | returns a XCFImage the width and height of the main image, with the layer rendered in the correct location |
null | false | true | returns a XCFImage the width and height of the layer |
XCFImage | true / false | false | returns the passed XCFImage unaltered |
XCFImage | true | true | returns the passed XCFImage with the layer rendered in the correct location |
XCFImage | false | true | returns the passed XCFImage with the layer rendered in the top left corner |
Properties
name
The name of the layer
width
The width of the layer
height
The height of the layer
x
The x offset of the layer on the base image
y
The y offset of the layer on the base image
Class XCFImage
The XCFImage
wraps round a pngjs-image object. See the docs of pngjs-image for details
The XCFImage
overwrites setAt(x,y,color) and getAt(x,y,colour) to provide functionality describe above