@itwin/core-frontend
Version:
iTwin.js frontend components
138 lines • 6.5 kB
JavaScript
;
/*---------------------------------------------------------------------------------------------
* Copyright (c) Bentley Systems, Incorporated. All rights reserved.
* See LICENSE.md in the project root for license terms and full copyright notice.
*--------------------------------------------------------------------------------------------*/
/** @packageDocumentation
* @module Views
*/
Object.defineProperty(exports, "__esModule", { value: true });
exports.SpriteLocation = exports.IconSprites = exports.Sprite = void 0;
const core_bentley_1 = require("@itwin/core-bentley");
const core_geometry_1 = require("@itwin/core-geometry");
const FrontendLoggerCategory_1 = require("./common/FrontendLoggerCategory");
const ImageUtil_1 = require("./common/ImageUtil");
/** Sprites are small raster images that are drawn *on top* of Viewports by a ViewDecoration.
* Their purpose is to draw the user's attention to something of importance.
*
* There are two classes in the Sprites subsystem: Sprite (a Sprite image) and SpriteLocation.
* Sprite are the images that define the way a type of sprite looks and are generally
* loaded one time and saved for the rest of a session. A SpriteLocation defines the current
* position of a single Sprite in a Viewport.
*
* A SpriteLocation can be either active or inactive. It becomes active by specifying a location
* (an x,y point) and a Sprite to draw at that point. A Sprite
* can be used many times by many SpriteLocations and a single SpriteLocation can
* change both position and which Sprite is shown at that position over time.
* @public
* @extensions
*/
class Sprite {
/** The image for this Sprite. If undefined, the Spite is not valid. */
image;
/** The size of this Sprite. If not loaded, value is not meaningful. */
size = new core_geometry_1.Point2d();
/** Promise fulfilled when this sprite is loaded. */
loadPromise;
/** The offset to the middle of this Sprite. If not loaded, value is not meaningful. */
get offset() { return new core_geometry_1.Point2d(Math.round(this.size.x) / 2, Math.round(this.size.y / 2)); }
/** Whether this sprite has be successfully loaded. */
get isLoaded() { return undefined !== this.image; }
/** construct a Sprite from an ImageSource or a Url
* @param src The ImageSource holding an image to create the texture for this Sprite, or the url of the image
*/
constructor(src) {
this.loadPromise = (typeof src === "string") ? (0, ImageUtil_1.imageElementFromUrl)(src) : (0, ImageUtil_1.imageElementFromImageSource)(src);
this.loadPromise.then((image) => {
this.image = image;
this.size.set(image.naturalWidth, image.naturalHeight);
}).catch((err) => {
const str = err.toString();
console.log(str); // eslint-disable-line no-console
core_bentley_1.Logger.logError(`${FrontendLoggerCategory_1.FrontendLoggerCategory.Package}.sprites`, str);
});
}
}
exports.Sprite = Sprite;
/** Icon sprites are loaded from .png files in the assets directory of imodeljs-native.
* They are cached by name, and the cache is cleared when the ToolAdmin is shut down.
* @public
* @extensions
*/
class IconSprites {
static _sprites = new Map();
/** Look up an IconSprite by url. If not loaded, create and load it.
* @param spriteUrl The url of an image to load for this Sprite.
*/
static getSpriteFromUrl(spriteUrl) {
let sprite = this._sprites.get(spriteUrl);
if (!sprite) {
sprite = new Sprite(spriteUrl);
this._sprites.set(spriteUrl, sprite);
}
return sprite;
}
/** Empty the cache, disposing all existing Sprites. */
static emptyAll() { this._sprites.clear(); }
}
exports.IconSprites = IconSprites;
/** A Sprite location. Sprites generally move around on the screen and this object holds the current location
* and current Sprite within a ScreenViewport. SpriteLocations can be either inactive (not visible) or active.
*
* A SpriteLocation can also specify that a Sprite should be drawn partially transparent.
* @public
* @extensions
*/
class SpriteLocation {
_viewport;
_sprite;
_alpha;
/** The current position of this sprite in view coordinates.
* @see [[CanvasDecoration.position]]
*/
position = new core_geometry_1.Point3d();
get isActive() { return this._viewport !== undefined; }
/** Activate this SpriteLocation to show a Sprite at a location in a single ScreenViewport.
* This call does not display the Sprite. Rather, subsequent calls to [[decorate]] from will show the Sprite.
* This SpriteLocation remains active until [[deactivate]] is called.
* @param sprite The Sprite to draw at this SpriteLocation
* @param viewport The Viewport onto which the Sprite is drawn
* @param locationWorld The position, in world coordinates
* @param alpha Optional alpha for the Sprite. Must be a number between 0 (fully transparent) and 1 (fully opaque).
*/
activate(sprite, viewport, locationWorld, alpha) {
this._sprite = sprite;
this._alpha = alpha;
this._viewport = viewport;
viewport.worldToView(locationWorld, this.position);
sprite.loadPromise.then(() => {
if (this._viewport === viewport) // was this deactivated while we were loading?
viewport.invalidateDecorations();
}).catch(() => this._viewport = undefined); // sprite was not loaded properly
}
/** Turn this SpriteLocation off so it will no longer show. */
deactivate() {
if (!this.isActive)
return;
this._viewport.invalidateDecorations();
this._viewport = undefined;
}
/** Draw this sprite onto the supplied canvas.
* @see [[CanvasDecoration.drawDecoration]]
*/
drawDecoration(ctx) {
const sprite = this._sprite;
if (undefined === sprite.image)
return;
if (undefined !== this._alpha)
ctx.globalAlpha = this._alpha;
ctx.drawImage(sprite.image, -sprite.offset.x, -sprite.offset.y);
}
/** If this SpriteLocation is active and the supplied DecorateContext is for its Viewport, add the Sprite to decorations. */
decorate(context) {
if (context.viewport === this._viewport)
context.addCanvasDecoration(this);
}
}
exports.SpriteLocation = SpriteLocation;
//# sourceMappingURL=Sprites.js.map