piskel/js/rendering/FrameRenderer.js

169 lines
5.1 KiB
JavaScript

(function () {
var ns = $.namespace("pskl.rendering");
/**
* FrameRenderer will display a given frame inside a canvas element.
* @param {HtmlElement} container HtmlElement to use as parentNode of the Frame
* @param {Object} renderingOptions
* @param {Array} classes array of strings to use for css classes
*/
ns.FrameRenderer = function (container, renderingOptions, classes) {
this.defaultRenderingOptions = {
'supportGridRendering' : false
};
renderingOptions = $.extend(true, {}, this.defaultRenderingOptions, renderingOptions);
if(container === undefined) {
throw 'Bad FrameRenderer initialization. <container> undefined.';
}
if(isNaN(renderingOptions.dpi)) {
throw 'Bad FrameRenderer initialization. <dpi> not well defined.';
}
this.container = container;
this.dpi = renderingOptions.dpi;
this.supportGridRendering = renderingOptions.supportGridRendering;
this.classes = classes || [];
this.classes.push('canvas');
this.canvas = null;
this.enableGrid(pskl.UserSettings.get(pskl.UserSettings.SHOW_GRID));
// Flag to know if the config was altered
this.canvasConfigDirty = true;
this.updateBackgroundClass_(pskl.UserSettings.get(pskl.UserSettings.CANVAS_BACKGROUND));
$.subscribe(Events.USER_SETTINGS_CHANGED, $.proxy(this.onUserSettingsChange_, this));
};
ns.FrameRenderer.prototype.updateDPI = function (newDPI) {
this.dpi = newDPI;
this.canvasConfigDirty = true;
};
/**
* @private
*/
ns.FrameRenderer.prototype.onUserSettingsChange_ = function (evt, settingName, settingValue) {
if(settingName == pskl.UserSettings.SHOW_GRID) {
this.enableGrid(settingValue);
}
else if (settingName == pskl.UserSettings.CANVAS_BACKGROUND) {
this.updateBackgroundClass_(settingValue);
}
};
/**
* @private
*/
ns.FrameRenderer.prototype.updateBackgroundClass_ = function (newClass) {
var currentClass = this.container.data('current-background-class');
if (currentClass) {
this.container.removeClass(currentClass);
}
this.container.addClass(newClass);
this.container.data('current-background-class', newClass);
};
ns.FrameRenderer.prototype.enableGrid = function (flag) {
this.gridStrokeWidth = (flag && this.supportGridRendering) ? Constants.GRID_STROKE_WIDTH : 0;
this.canvasConfigDirty = true;
};
ns.FrameRenderer.prototype.render = function (frame) {
if (frame) {
this.clear();
var context = this.getCanvas_(frame).getContext('2d');
for(var col = 0, width = frame.getWidth(); col < width; col++) {
for(var row = 0, height = frame.getHeight(); row < height; row++) {
var color = frame.getPixel(col, row);
this.renderPixel_(color, col, row, context);
}
}
this.lastRenderedFrame = frame;
}
};
ns.FrameRenderer.prototype.renderPixel_ = function (color, col, row, context) {
if(color != Constants.TRANSPARENT_COLOR) {
context.fillStyle = color;
context.fillRect(this.getFramePos_(col), this.getFramePos_(row), this.dpi, this.dpi);
}
};
ns.FrameRenderer.prototype.clear = function () {
if (this.canvas) {
this.canvas.getContext("2d").clearRect(0, 0, this.canvas.width, this.canvas.height);
}
};
/**
* Transform a screen pixel-based coordinate (relative to the top-left corner of the rendered
* frame) into a sprite coordinate in column and row.
* @public
*/
ns.FrameRenderer.prototype.convertPixelCoordinatesIntoSpriteCoordinate = function(coords) {
var cellSize = this.dpi + this.gridStrokeWidth;
return {
"col" : (coords.x - coords.x % cellSize) / cellSize,
"row" : (coords.y - coords.y % cellSize) / cellSize
};
};
/**
* @private
*/
ns.FrameRenderer.prototype.getFramePos_ = function(index) {
return index * this.dpi + ((index - 1) * this.gridStrokeWidth);
};
/**
* @private
*/
ns.FrameRenderer.prototype.drawGrid_ = function(canvas, width, height, col, row) {
var ctx = canvas.getContext("2d");
ctx.lineWidth = Constants.GRID_STROKE_WIDTH;
ctx.strokeStyle = Constants.GRID_STROKE_COLOR;
for(var c=1; c < col; c++) {
ctx.moveTo(this.getFramePos_(c), 0);
ctx.lineTo(this.getFramePos_(c), height);
ctx.stroke();
}
for(var r=1; r < row; r++) {
ctx.moveTo(0, this.getFramePos_(r));
ctx.lineTo(width, this.getFramePos_(r));
ctx.stroke();
}
};
/**
* @private
*/
ns.FrameRenderer.prototype.getCanvas_ = function (frame) {
if(this.canvasConfigDirty) {
$(this.canvas).remove();
var col = frame.getWidth(),
row = frame.getHeight();
var pixelWidth = col * this.dpi + this.gridStrokeWidth * (col - 1);
var pixelHeight = row * this.dpi + this.gridStrokeWidth * (row - 1);
var canvas = pskl.CanvasUtils.createCanvas(pixelWidth, pixelHeight, this.classes);
this.container.append(canvas);
if(this.gridStrokeWidth > 0) {
this.drawGrid_(canvas, pixelWidth, pixelHeight, col, row);
}
this.canvas = canvas;
this.canvasConfigDirty = false;
}
return this.canvas;
};
})();