phaser/src/textures/parsers/SpriteSheet.js

119 lines
3.6 KiB
JavaScript

/**
* @author Richard Davey <rich@photonstorm.com>
* @copyright 2018 Photon Storm Ltd.
* @license {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
*/
var GetFastValue = require('../../utils/object/GetFastValue');
/**
* Parses a Sprite Sheet and adds the Frames to the Texture.
*
* In Phaser terminology a Sprite Sheet is a texture containing different frames, but each frame is the exact
* same size and cannot be trimmed or rotated.
*
* @function Phaser.Textures.Parsers.SpriteSheet
* @memberOf Phaser.Textures.Parsers
* @private
* @since 3.0.0
*
* @param {Phaser.Textures.Texture} texture - The Texture to add the Frames to.
* @param {integer} sourceIndex - The index of the TextureSource.
* @param {integer} x - [description]
* @param {integer} y - [description]
* @param {integer} width - [description]
* @param {integer} height - [description]
* @param {object} config - An object describing how to parse the Sprite Sheet.
* @param {number} config.frameWidth - Width in pixels of a single frame in the sprite sheet.
* @param {number} [config.frameHeight] - Height in pixels of a single frame in the sprite sheet. Defaults to frameWidth if not provided.
* @param {number} [config.startFrame=0] - [description]
* @param {number} [config.endFrame=-1] - [description]
* @param {number} [config.margin=0] - If the frames have been drawn with a margin, specify the amount here.
* @param {number} [config.spacing=0] - If the frames have been drawn with spacing between them, specify the amount here.
*
* @return {Phaser.Textures.Texture} The Texture modified by this parser.
*/
var SpriteSheet = function (texture, sourceIndex, x, y, width, height, config)
{
var frameWidth = GetFastValue(config, 'frameWidth', null);
var frameHeight = GetFastValue(config, 'frameHeight', frameWidth);
// If missing we can't proceed
if (frameWidth === null)
{
throw new Error('TextureManager.SpriteSheet: Invalid frameWidth given.');
}
// Add in a __BASE entry (for the entire atlas)
var source = texture.source[sourceIndex];
texture.add('__BASE', sourceIndex, 0, 0, source.width, source.height);
var startFrame = GetFastValue(config, 'startFrame', 0);
var endFrame = GetFastValue(config, 'endFrame', -1);
var margin = GetFastValue(config, 'margin', 0);
var spacing = GetFastValue(config, 'spacing', 0);
var row = Math.floor((width - margin + spacing) / (frameWidth + spacing));
var column = Math.floor((height - margin + spacing) / (frameHeight + spacing));
var total = row * column;
if (total === 0)
{
console.warn('SpriteSheet frame dimensions will result in zero frames.');
}
if (startFrame > total || startFrame < -total)
{
startFrame = 0;
}
if (startFrame < 0)
{
// Allow negative skipframes.
startFrame = total + startFrame;
}
if (endFrame !== -1)
{
total = startFrame + (endFrame + 1);
}
var fx = margin;
var fy = margin;
var ax = 0;
var ay = 0;
for (var i = 0; i < total; i++)
{
ax = 0;
ay = 0;
var w = fx + frameWidth;
var h = fy + frameHeight;
if (w > width)
{
ax = w - width;
}
if (h > height)
{
ay = h - height;
}
texture.add(i, sourceIndex, x + fx, y + fy, frameWidth - ax, frameHeight - ay);
fx += frameWidth + spacing;
if (fx + frameWidth > width)
{
fx = margin;
fy += frameHeight + spacing;
}
}
return texture;
};
module.exports = SpriteSheet;