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import renderingEngineCache from './renderingEngineCache';
import eventTarget from '../eventTarget';
import { triggerEvent, uuidv4 } from '../utilities';
import { vtkOffscreenMultiRenderWindow } from './vtkClasses';
import ViewportType from '../enums/ViewportType';
import VolumeViewport from './VolumeViewport';
import BaseVolumeViewport from './BaseVolumeViewport';
import StackViewport from './StackViewport';
import viewportTypeUsesCustomRenderingPipeline from './helpers/viewportTypeUsesCustomRenderingPipeline';
import getOrCreateCanvas from './helpers/getOrCreateCanvas';
import { getShouldUseCPURendering, isCornerstoneInitialized } from '../init';
import type IStackViewport from '../types/IStackViewport';
import type IVideoViewport from '../types/IVideoViewport';
import type IRenderingEngine from '../types/IRenderingEngine';
import type IVolumeViewport from '../types/IVolumeViewport';
import type { IViewport } from '../types/IViewport';
import VideoViewport from './VideoViewport';
import viewportTypeToViewportClass from './helpers/viewportTypeToViewportClass';
import type * as EventTypes from '../types/EventTypes';
import type {
ViewportInput,
PublicViewportInput,
InternalViewportInput,
NormalizedViewportInput,
} from '../types/IViewport';
import { OrientationAxis } from '../enums';
import VolumeViewport3D from './VolumeViewport3D';
type ViewportDisplayCoords = {
sxStartDisplayCoords: number;
syStartDisplayCoords: number;
sxEndDisplayCoords: number;
syEndDisplayCoords: number;
sx: number;
sy: number;
sWidth: number;
sHeight: number;
};
// Rendering engines seem to not like rendering things less than 2 pixels per side
const VIEWPORT_MIN_SIZE = 2;
/**
* A RenderingEngine takes care of the full pipeline of creating viewports and rendering
* them on a large offscreen canvas and transmitting this data back to the screen. This allows us
* to leverage the power of vtk.js whilst only using one WebGL context for the processing, and allowing
* us to share texture memory across on-screen viewports that show the same data.
*
*
* Instantiating a rendering engine:
* ```js
* const renderingEngine = new RenderingEngine('pet-ct-rendering-engine');
* ```
*
* There are various ways you can trigger a render on viewports. The simplest is to call `render()`
* on the rendering engine; however, it will trigger a render on all viewports. A more efficient
* way to do this is to call `renderViewports([viewportId])` on the rendering engine to
* trigger a render on a specific viewport(s). Each viewport also has a `.render` method which can be used to trigger a render on that
* viewport.
*
*
* Rendering engine uses `detect-gpu` external library to detect if GPU is available and
* it has minimum requirement to be able to render a volume with vtk.js. If GPU is not available
* RenderingEngine will throw an error if you try to render a volume; however, for StackViewports
* it is capable of falling back to CPU rendering for Stack images.
*
* By default RenderingEngine will use vtk.js enabled pipeline for rendering viewports,
* however, if a custom rendering pipeline is specified by a custom viewport, it will be used instead.
* We use this custom pipeline to render a StackViewport on CPU using Cornerstone-legacy cpu rendering pipeline.
*
* @public
*/
class RenderingEngine implements IRenderingEngine {
/** Unique identifier for renderingEngine */
readonly id: string;
/** A flag which tells if the renderingEngine has been destroyed or not */
public hasBeenDestroyed: boolean;
public offscreenMultiRenderWindow: any;
readonly offScreenCanvasContainer: any; // WebGL
private _viewports: Map<string, IViewport>;
private _needsRender: Set<string> = new Set();
private _animationFrameSet = false;
private _animationFrameHandle: number | null = null;
private useCPURendering: boolean;
/**
* @param uid - Unique identifier for RenderingEngine
*/
constructor(id?: string) {
this.id = id ? id : uuidv4();
this.useCPURendering = getShouldUseCPURendering();
renderingEngineCache.set(this);
Iif (!isCornerstoneInitialized()) {
throw new Error(
'@cornerstonejs/core is not initialized, run init() first'
);
}
if (!this.useCPURendering) {
this.offscreenMultiRenderWindow =
vtkOffscreenMultiRenderWindow.newInstance();
this.offScreenCanvasContainer = document.createElement('div');
this.offscreenMultiRenderWindow.setContainer(
this.offScreenCanvasContainer
);
}
this._viewports = new Map();
this.hasBeenDestroyed = false;
}
/**
* Enables the requested viewport and add it to the viewports. It will
* properly create the Stack viewport or Volume viewport:
*
* 1) Checks if the viewport is defined already, if yes, remove it first
* 2) Checks if the viewport is using a custom rendering pipeline, if no,
* it calculates a new offscreen canvas with the new requested viewport
* 3) Adds the viewport
*
*
* ```
* renderingEngine.enableElement({
* viewportId: viewportId,
* type: ViewportType.ORTHOGRAPHIC,
* element,
* defaultOptions: {
* orientation: Enums.OrientationAxis.AXIAL,
* background: [1, 0, 1],
* },
* })
* ```
*
* @fires Events.ELEMENT_ENABLED
*
* @param viewportInputEntry - viewport specifications
*/
public enableElement(viewportInputEntry: PublicViewportInput): void {
const viewportInput = this._normalizeViewportInputEntry(viewportInputEntry);
this._throwIfDestroyed();
const { element, viewportId } = viewportInput;
// Throw error if no canvas
Iif (!element) {
throw new Error('No element provided');
}
// 1. Get the viewport from the list of available viewports.
const viewport = this.getViewport(viewportId);
// 1.a) If there is a found viewport, we remove the viewport and create a new viewport
Iif (viewport) {
this.disableElement(viewportId);
}
// 2.a) See if viewport uses a custom rendering pipeline.
const { type } = viewportInput;
const viewportUsesCustomRenderingPipeline =
viewportTypeUsesCustomRenderingPipeline(type);
// 2.b) Retrieving the list of viewports for calculation of the new size for
// offScreen canvas.
// If the viewport being added uses a custom pipeline, or we aren't using
// GPU rendering, we don't need to resize the offscreen canvas.
if (!this.useCPURendering && !viewportUsesCustomRenderingPipeline) {
this.enableVTKjsDrivenViewport(viewportInput);
} else E{
// 3 Add the requested viewport to rendering Engine
this.addCustomViewport(viewportInput);
}
// 5. Set the background color for the canvas
const canvas = getOrCreateCanvas(element);
const { background } = viewportInput.defaultOptions;
this.fillCanvasWithBackgroundColor(canvas, background);
}
/**
* Disables the requested viewportId from the rendering engine:
*
* 1) It removes the viewport from the the list of viewports
* 2) remove the renderer from the offScreen render window if using vtk.js driven
* rendering pipeline
* 3) resetting the viewport to remove the canvas attributes and canvas data
* 4) resize the offScreen appropriately (if using vtk.js driven rendering pipeline)
*
* @fires Events.ELEMENT_ENABLED
*
* @param viewportId - viewport Id
*
*/
public disableElement(viewportId: string): void {
this._throwIfDestroyed();
// 1. Getting the viewport to remove it
const viewport = this.getViewport(viewportId);
// 2 To throw if there is no viewport stored in rendering engine
Iif (!viewport) {
console.warn(`viewport ${viewportId} does not exist`);
return;
}
// 3. Reset the viewport to remove attributes, and reset the canvas
this._resetViewport(viewport);
// 4. Remove the related renderer from the offScreenMultiRenderWindow
if (
!viewportTypeUsesCustomRenderingPipeline(viewport.type) &&
!this.useCPURendering
) {
this.offscreenMultiRenderWindow.removeRenderer(viewportId);
}
// 5. Remove the requested viewport from the rendering engine
this._removeViewport(viewportId);
viewport.isDisabled = true;
// 6. Avoid rendering for the disabled viewport
this._needsRender.delete(viewportId);
// 7. Clear RAF if no viewport is left
const viewports = this.getViewports();
Eif (!viewports.length) {
this._clearAnimationFrame();
}
// Note: we should not call resize at the end of here, the reason is that
// in batch rendering, we might disable a viewport and enable others at the same
// time which would interfere with each other. So we just let the enable
// to call resize, and also resize getting called by applications on the
// DOM resize event.
}
/**
* It takes an array of viewport input objects including element, viewportId, type
* and defaultOptions. It will add the viewport to the rendering engine and enables them.
*
*
* ```typescript
*renderingEngine.setViewports([
* {
* viewportId: axialViewportId,
* type: ViewportType.ORTHOGRAPHIC,
* element: document.getElementById('axialDiv'),
* defaultOptions: {
* orientation: Enums.OrientationAxis.AXIAL,
* },
* },
* {
* viewportId: sagittalViewportId,
* type: ViewportType.ORTHOGRAPHIC,
* element: document.getElementById('sagittalDiv'),
* defaultOptions: {
* orientation: Enums.OrientationAxis.SAGITTAL,
* },
* },
* {
* viewportId: customOrientationViewportId,
* type: ViewportType.ORTHOGRAPHIC,
* element: document.getElementById('customOrientationDiv'),
* defaultOptions: {
* orientation: { viewPlaneNormal: [0, 0, 1], viewUp: [0, 1, 0] },
* },
* },
* ])
* ```
*
* @fires Events.ELEMENT_ENABLED
*
* @param viewportInputEntries - Array<PublicViewportInput>
*/
public setViewports(
publicViewportInputEntries: Array<PublicViewportInput>
): void {
const viewportInputEntries = this._normalizeViewportInputEntries(
publicViewportInputEntries
);
this._throwIfDestroyed();
this._reset();
// 1. Split viewports based on whether they use vtk.js or a custom pipeline.
const vtkDrivenViewportInputEntries: NormalizedViewportInput[] = [];
const customRenderingViewportInputEntries: NormalizedViewportInput[] = [];
viewportInputEntries.forEach((vpie) => {
if (
!this.useCPURendering &&
!viewportTypeUsesCustomRenderingPipeline(vpie.type)
) {
vtkDrivenViewportInputEntries.push(vpie);
} else {
customRenderingViewportInputEntries.push(vpie);
}
});
this.setVtkjsDrivenViewports(vtkDrivenViewportInputEntries);
this.setCustomViewports(customRenderingViewportInputEntries);
// Making sure the setViewports api also can fill the canvas
// properly
viewportInputEntries.forEach((vp) => {
const canvas = getOrCreateCanvas(vp.element);
const { background } = vp.defaultOptions;
this.fillCanvasWithBackgroundColor(canvas, background);
});
}
/**
* Resizes the offscreen viewport and recalculates translations to on screen canvases.
* It is up to the parent app to call the resize of the on-screen canvas changes.
* This is left as an app level concern as one might want to debounce the changes, or the like.
*
* @param immediate - Whether all of the viewports should be rendered immediately.
* @param keepCamera - Whether to keep the camera for other viewports while resizing the offscreen canvas
*/
public resize(immediate = true, keepCamera = true): void {
this._throwIfDestroyed();
// 1. Get the viewports' canvases
const viewports = this._getViewportsAsArray();
const vtkDrivenViewports = [];
const customRenderingViewports = [];
viewports.forEach((vpie) => {
if (!viewportTypeUsesCustomRenderingPipeline(vpie.type)) {
vtkDrivenViewports.push(vpie);
} else {
customRenderingViewports.push(vpie);
}
});
if (vtkDrivenViewports.length) {
this._resizeVTKViewports(vtkDrivenViewports, keepCamera, immediate);
}
if (customRenderingViewports.length) {
this._resizeUsingCustomResizeHandler(
customRenderingViewports,
keepCamera,
immediate
);
}
}
/**
* Returns the viewport by Id
*
* @returns viewport
*/
public getViewport(viewportId: string): IViewport {
return this._viewports.get(viewportId);
}
/**
* getViewports Returns an array of all `Viewport`s on the `RenderingEngine` instance.
*
* @returns Array of viewports
*/
public getViewports(): Array<IViewport> {
this._throwIfDestroyed();
return this._getViewportsAsArray();
}
/**
* Filters all the available viewports and return the stack viewports
* @returns stack viewports registered on the rendering Engine
*/
public getStackViewports(): Array<IStackViewport> {
this._throwIfDestroyed();
const viewports = this.getViewports();
const isStackViewport = (
viewport: IViewport
): viewport is StackViewport => {
return viewport instanceof StackViewport;
};
return viewports.filter(isStackViewport) as Array<IStackViewport>;
}
/**
* Filters all the available viewports and return the stack viewports
* @returns stack viewports registered on the rendering Engine
*/
public getVideoViewports(): Array<IVideoViewport> {
this._throwIfDestroyed();
const viewports = this.getViewports();
const isVideoViewport = (
viewport: IViewport
): viewport is VideoViewport => {
return viewport instanceof VideoViewport;
};
return viewports.filter(isVideoViewport) as Array<IVideoViewport>;
}
/**
* Return all the viewports that are volume viewports
* @returns An array of VolumeViewport objects.
*/
public getVolumeViewports(): Array<IVolumeViewport> {
this._throwIfDestroyed();
const viewports = this.getViewports();
const isVolumeViewport = (
viewport: IViewport
): viewport is BaseVolumeViewport => {
return viewport instanceof BaseVolumeViewport;
};
return viewports.filter(isVolumeViewport);
}
/**
* Renders all viewports on the next animation frame.
*
* @fires Events.IMAGE_RENDERED
*/
public render(): void {
const viewports = this.getViewports();
const viewportIds = viewports.map((vp) => vp.id);
this._setViewportsToBeRenderedNextFrame(viewportIds);
}
/**
* Renders any viewports viewing the given Frame Of Reference.
*
* @param FrameOfReferenceUID - The unique identifier of the
* Frame Of Reference.
*/
public renderFrameOfReference = (FrameOfReferenceUID: string): void => {
const viewports = this._getViewportsAsArray();
const viewportIdsWithSameFrameOfReferenceUID = viewports.map((vp) => {
Eif (vp.getFrameOfReferenceUID() === FrameOfReferenceUID) {
return vp.id;
}
});
return this.renderViewports(viewportIdsWithSameFrameOfReferenceUID);
};
/**
* Renders the provided Viewport IDs.
*
*/
public renderViewports(viewportIds: Array<string>): void {
this._setViewportsToBeRenderedNextFrame(viewportIds);
}
/**
* Renders only a specific `Viewport` on the next animation frame.
*
* @param viewportId - The Id of the viewport.
*/
public renderViewport(viewportId: string): void {
this._setViewportsToBeRenderedNextFrame([viewportId]);
}
/**
* destroy the rendering engine. It will remove all the viewports and,
* if the rendering engine is using the GPU, it will also destroy the GPU
* resources.
*/
public destroy(): void {
if (this.hasBeenDestroyed) {
return;
}
// remove vtk rendered first before resetting the viewport
if (!this.useCPURendering) {
const viewports = this._getViewportsAsArray();
viewports.forEach((vp) => {
this.offscreenMultiRenderWindow.removeRenderer(vp.id);
});
// Free up WebGL resources
this.offscreenMultiRenderWindow.delete();
// Make sure all references go stale and are garbage collected.
delete this.offscreenMultiRenderWindow;
}
this._reset();
renderingEngineCache.delete(this.id);
this.hasBeenDestroyed = true;
}
/**
* Fill the canvas with the background color
* @param canvas - The canvas element to draw on.
* @param backgroundColor - An array of three numbers between 0 and 1 that
* specify the red, green, and blue values of the background color.
*/
public fillCanvasWithBackgroundColor(
canvas: HTMLCanvasElement,
backgroundColor: [number, number, number]
): void {
const ctx = canvas.getContext('2d');
// Default to black if no background color is set
let fillStyle;
if (backgroundColor) {
const rgb = backgroundColor.map((f) => Math.floor(255 * f));
fillStyle = `rgb(${rgb[0]}, ${rgb[1]}, ${rgb[2]})`;
} else {
fillStyle = 'black';
}
// We draw over the previous stack with the background color while we
// wait for the next stack to load
ctx.fillStyle = fillStyle;
ctx.fillRect(0, 0, canvas.width, canvas.height);
}
private _normalizeViewportInputEntry(
viewportInputEntry: PublicViewportInput
) {
const { type, defaultOptions } = viewportInputEntry;
let options = defaultOptions;
Iif (!options || Object.keys(options).length === 0) {
options = {
background: [0, 0, 0],
orientation: null,
displayArea: null,
};
if (type === ViewportType.ORTHOGRAPHIC) {
options = {
...options,
orientation: OrientationAxis.AXIAL,
};
}
}
return {
...viewportInputEntry,
defaultOptions: options,
};
}
private _normalizeViewportInputEntries(
viewportInputEntries: Array<PublicViewportInput>
): Array<NormalizedViewportInput> {
const normalizedViewportInputs = [];
viewportInputEntries.forEach((viewportInput) => {
normalizedViewportInputs.push(
this._normalizeViewportInputEntry(viewportInput)
);
});
return normalizedViewportInputs;
}
private _resizeUsingCustomResizeHandler(
customRenderingViewports: StackViewport[],
keepCamera = true,
immediate = true
) {
// 1. If viewport has a custom resize method, call it here.
customRenderingViewports.forEach((vp) => {
if (typeof vp.resize === 'function') {
vp.resize();
}
});
// 3. Reset viewport cameras
customRenderingViewports.forEach((vp) => {
const prevCamera = vp.getCamera();
vp.resetCamera();
if (keepCamera) {
vp.setCamera(prevCamera);
}
});
// 2. If render is immediate: Render all
if (immediate === true) {
this.render();
}
}
private _resizeVTKViewports(
vtkDrivenViewports: Array<IStackViewport | IVolumeViewport>,
keepCamera = true,
immediate = true
) {
// Ensure all the canvases are ready for rendering
vtkDrivenViewports.forEach((vp: IStackViewport | IVolumeViewport) => {
getOrCreateCanvas(vp.element);
});
const canvasesDrivenByVtkJs = vtkDrivenViewports.map((vp) => vp.canvas);
if (canvasesDrivenByVtkJs.length) {
// 1. Recalculate and resize the offscreen canvas size
const { offScreenCanvasWidth, offScreenCanvasHeight } =
this._resizeOffScreenCanvas(canvasesDrivenByVtkJs);
// 2. Recalculate the viewports location on the off screen canvas
this._resize(
vtkDrivenViewports,
offScreenCanvasWidth,
offScreenCanvasHeight
);
}
// 3. Reset viewport cameras
vtkDrivenViewports.forEach((vp: IStackViewport | IVolumeViewport) => {
const prevCamera = vp.getCamera();
const rotation = vp.getRotation();
const { flipHorizontal } = prevCamera;
vp.resetCamera();
const displayArea = vp.getDisplayArea();
// TODO - make this use get/set Presentation or in some way preserve the
// basic presentation info on this viewport, rather than preserving camera
if (keepCamera) {
if (displayArea) {
if (flipHorizontal) {
vp.setCamera({ flipHorizontal });
}
if (rotation) {
vp.setProperties({ rotation });
}
} else {
vp.setCamera(prevCamera);
}
}
});
// 4. If render is immediate: Render all
if (immediate === true) {
this.render();
}
}
/**
* Enables a viewport to be driven by the offscreen vtk.js rendering engine.
*
* @param viewportInputEntry - Information object used to
* construct and enable the viewport.
*/
private enableVTKjsDrivenViewport(
viewportInputEntry: NormalizedViewportInput
) {
const viewports = this._getViewportsAsArray();
const viewportsDrivenByVtkJs = viewports.filter(
(vp) => viewportTypeUsesCustomRenderingPipeline(vp.type) === false
);
const canvasesDrivenByVtkJs = viewportsDrivenByVtkJs.map((vp) => vp.canvas);
const canvas = getOrCreateCanvas(viewportInputEntry.element);
canvasesDrivenByVtkJs.push(canvas);
// 2.c Calculating the new size for offScreen Canvas
const { offScreenCanvasWidth, offScreenCanvasHeight } =
this._resizeOffScreenCanvas(canvasesDrivenByVtkJs);
// 2.d Re-position previous viewports on the offScreen Canvas based on the new
// offScreen canvas size
const xOffset = this._resize(
viewportsDrivenByVtkJs,
offScreenCanvasWidth,
offScreenCanvasHeight
);
const internalViewportEntry = { ...viewportInputEntry, canvas };
// 3 Add the requested viewport to rendering Engine
this.addVtkjsDrivenViewport(internalViewportEntry, {
offScreenCanvasWidth,
offScreenCanvasHeight,
xOffset,
});
}
/**
* Disables the requested viewportId from the rendering engine:
* 1) It removes the viewport from the the list of viewports
* 2) remove the renderer from the offScreen render window
* 3) resetting the viewport to remove the canvas attributes and canvas data
* 4) resize the offScreen appropriately
*
* @param viewportId - viewport Id
*
*/
private _removeViewport(viewportId: string): void {
// 1. Get the viewport
const viewport = this.getViewport(viewportId);
Iif (!viewport) {
console.warn(`viewport ${viewportId} does not exist`);
return;
}
// 2. Delete the viewports from the the viewports
this._viewports.delete(viewportId);
}
/**
* Adds a viewport driven by vtk.js to the `RenderingEngine`.
*
* @param viewportInputEntry - Information object used to construct and enable the viewport.
* @param options - Options object used to configure the viewport.
* @param options.offScreenCanvasWidth - The width of the offscreen canvas.
* @param options.offScreenCanvasHeight - The height of the offscreen canvas.
* @param options.xOffset - The x offset of the viewport on the offscreen canvas.
*/
private addVtkjsDrivenViewport(
viewportInputEntry: InternalViewportInput,
offscreenCanvasProperties?: {
offScreenCanvasWidth: number;
offScreenCanvasHeight: number;
xOffset: number;
}
): void {
const { element, canvas, viewportId, type, defaultOptions } =
viewportInputEntry;
// Make the element not focusable, we use this for modifier keys to work
element.tabIndex = -1;
const { offScreenCanvasWidth, offScreenCanvasHeight, xOffset } =
offscreenCanvasProperties;
// 1. Calculate the size of location of the viewport on the offScreen canvas
const {
sxStartDisplayCoords,
syStartDisplayCoords,
sxEndDisplayCoords,
syEndDisplayCoords,
sx,
sy,
sWidth,
sHeight,
} = this._getViewportCoordsOnOffScreenCanvas(
viewportInputEntry,
offScreenCanvasWidth,
offScreenCanvasHeight,
xOffset
);
// 2. Add a renderer to the offScreenMultiRenderWindow
this.offscreenMultiRenderWindow.addRenderer({
viewport: [
sxStartDisplayCoords,
syStartDisplayCoords,
sxEndDisplayCoords,
syEndDisplayCoords,
],
id: viewportId,
background: defaultOptions.background
? defaultOptions.background
: [0, 0, 0],
});
// 3. ViewportInput to be passed to a stack/volume viewport
const viewportInput = <ViewportInput>{
id: viewportId,
element, // div
renderingEngineId: this.id,
type,
canvas,
sx,
sy,
sWidth,
sHeight,
defaultOptions: defaultOptions || {},
};
// 4. Create a proper viewport based on the type of the viewport
let viewport;
if (type === ViewportType.STACK) {
// 4.a Create stack viewport
viewport = new StackViewport(viewportInput);
} else if (
type === ViewportType.ORTHOGRAPHIC ||
type === ViewportType.PERSPECTIVE
) {
// 4.b Create a volume viewport
viewport = new VolumeViewport(viewportInput);
} else if (type === ViewportType.VOLUME_3D) {
viewport = new VolumeViewport3D(viewportInput);
} else E{
throw new Error(`Viewport Type ${type} is not supported`);
}
// 5. Storing the viewports
this._viewports.set(viewportId, viewport);
const eventDetail: EventTypes.ElementEnabledEventDetail = {
element,
viewportId,
renderingEngineId: this.id,
};
if (!viewport.suppressEvents) {
triggerEvent(eventTarget, Events.ELEMENT_ENABLED, eventDetail);
}
}
/**
* Adds a viewport using a custom rendering pipeline to the `RenderingEngine`.
*
* @param viewportInputEntry - Information object used to
* construct and enable the viewport.
*/
private addCustomViewport(viewportInputEntry: PublicViewportInput): void {
const { element, viewportId, type, defaultOptions } = viewportInputEntry;
// Make the element not focusable, we use this for modifier keys to work
element.tabIndex = -1;
const canvas = getOrCreateCanvas(element);
// Add a viewport with no offset
const { clientWidth, clientHeight } = canvas;
// Set the canvas to be same resolution as the client.
// Note: This ignores devicePixelRatio for now. We may want to change it in the
// future but it has no benefit for the Cornerstone CPU rendering pathway at the
// moment anyway.
Iif (canvas.width !== clientWidth || canvas.height !== clientHeight) {
canvas.width = clientWidth;
canvas.height = clientHeight;
}
const viewportInput = <ViewportInput>{
id: viewportId,
renderingEngineId: this.id,
element, // div
type,
canvas,
sx: 0, // No offset, uses own renderer
sy: 0,
sWidth: clientWidth,
sHeight: clientHeight,
defaultOptions: defaultOptions || {},
};
// 4. Create a proper viewport based on the type of the viewport
const ViewportType = viewportTypeToViewportClass[type];
const viewport = new ViewportType(viewportInput);
// 5. Storing the viewports
this._viewports.set(viewportId, viewport);
const eventDetail: EventTypes.ElementEnabledEventDetail = {
element,
viewportId,
renderingEngineId: this.id,
};
triggerEvent(eventTarget, Events.ELEMENT_ENABLED, eventDetail);
}
/**
* Sets multiple viewports using custom rendering
* pipelines to the `RenderingEngine`.
*
* @param viewportInputEntries - An array of information
* objects used to construct and enable the viewports.
*/
private setCustomViewports(viewportInputEntries: PublicViewportInput[]) {
viewportInputEntries.forEach((vpie) => this.addCustomViewport(vpie));
}
/**
* Sets multiple vtk.js driven viewports to
* the `RenderingEngine`.
*
* @param viewportInputEntries - An array of information
* objects used to construct and enable the viewports.
*/
private setVtkjsDrivenViewports(
viewportInputEntries: NormalizedViewportInput[]
) {
// Deal with vtkjs driven viewports
if (viewportInputEntries.length) {
// 1. Getting all the canvases from viewports calculation of the new offScreen size
const vtkDrivenCanvases = viewportInputEntries.map((vp) =>
getOrCreateCanvas(vp.element)
);
// Ensure the canvas size includes any scaling due to device pixel ratio
vtkDrivenCanvases.forEach((canvas) => {
const devicePixelRatio = window.devicePixelRatio || 1;
const rect = canvas.getBoundingClientRect();
canvas.width = rect.width * devicePixelRatio;
canvas.height = rect.height * devicePixelRatio;
});
// 2. Set canvas size based on height and sum of widths
const { offScreenCanvasWidth, offScreenCanvasHeight } =
this._resizeOffScreenCanvas(vtkDrivenCanvases);
/*
TODO: Commenting this out until we can mock the Canvas usage in the tests (or use jsdom?)
if (!offScreenCanvasWidth || !offScreenCanvasHeight) {
throw new Error('Invalid offscreen canvas width or height')
}*/
// 3. Adding the viewports based on the viewportInputEntry definition to the
// rendering engine.
let xOffset = 0;
for (let i = 0; i < viewportInputEntries.length; i++) {
const vtkDrivenViewportInputEntry = viewportInputEntries[i];
const canvas = vtkDrivenCanvases[i];
const internalViewportEntry = {
...vtkDrivenViewportInputEntry,
canvas,
};
this.addVtkjsDrivenViewport(internalViewportEntry, {
offScreenCanvasWidth,
offScreenCanvasHeight,
xOffset,
});
// Incrementing the xOffset which provides the horizontal location of each
// viewport on the offScreen canvas
xOffset += canvas.width;
}
}
}
/**
* Resizes the offscreen canvas based on the provided vtk.js driven canvases.
*
* @param canvases - An array of HTML Canvas
*/
private _resizeOffScreenCanvas(
canvasesDrivenByVtkJs: Array<HTMLCanvasElement>
): { offScreenCanvasWidth: number; offScreenCanvasHeight: number } {
const { offScreenCanvasContainer, offscreenMultiRenderWindow } = this;
// 1. Calculated the height of the offScreen canvas to be the maximum height
// between canvases
const offScreenCanvasHeight = Math.max(
...canvasesDrivenByVtkJs.map((canvas) => canvas.height)
);
// 2. Calculating the width of the offScreen canvas to be the sum of all
let offScreenCanvasWidth = 0;
canvasesDrivenByVtkJs.forEach((canvas) => {
offScreenCanvasWidth += canvas.width;
});
offScreenCanvasContainer.width = offScreenCanvasWidth;
offScreenCanvasContainer.height = offScreenCanvasHeight;
// 3. Resize command
offscreenMultiRenderWindow.resize();
return { offScreenCanvasWidth, offScreenCanvasHeight };
}
/**
* Recalculates and updates the viewports location on the offScreen canvas upon its resize
*
* @param viewports - An array of viewports
* @param offScreenCanvasWidth - new offScreen canvas width
* @param offScreenCanvasHeight - new offScreen canvas height
*
* @returns _xOffset the final offset which will be used for the next viewport
*/
private _resize(
viewportsDrivenByVtkJs: Array<IViewport>,
offScreenCanvasWidth: number,
offScreenCanvasHeight: number
): number {
// Redefine viewport properties
let _xOffset = 0;
for (let i = 0; i < viewportsDrivenByVtkJs.length; i++) {
const viewport = viewportsDrivenByVtkJs[i];
const {
sxStartDisplayCoords,
syStartDisplayCoords,
sxEndDisplayCoords,
syEndDisplayCoords,
sx,
sy,
sWidth,
sHeight,
} = this._getViewportCoordsOnOffScreenCanvas(
viewport,
offScreenCanvasWidth,
offScreenCanvasHeight,
_xOffset
);
_xOffset += viewport.canvas.width;
viewport.sx = sx;
viewport.sy = sy;
viewport.sWidth = sWidth;
viewport.sHeight = sHeight;
// Updating the renderer for the viewport
const renderer = this.offscreenMultiRenderWindow.getRenderer(viewport.id);
renderer.setViewport([
sxStartDisplayCoords,
syStartDisplayCoords,
sxEndDisplayCoords,
syEndDisplayCoords,
]);
}
// Returns the final xOffset
return _xOffset;
}
/**
* Calculates the location of the provided viewport on the offScreenCanvas
*
* @param viewports - An array of viewports
* @param offScreenCanvasWidth - new offScreen canvas width
* @param offScreenCanvasHeight - new offScreen canvas height
* @param _xOffset - xOffSet to draw
*/
private _getViewportCoordsOnOffScreenCanvas(
viewport: InternalViewportInput | IViewport,
offScreenCanvasWidth: number,
offScreenCanvasHeight: number,
_xOffset: number
): ViewportDisplayCoords {
const { canvas } = viewport;
const { width: sWidth, height: sHeight } = canvas;
// Update the canvas drawImage offsets.
const sx = _xOffset;
const sy = 0;
const sxStartDisplayCoords = sx / offScreenCanvasWidth;
// Need to offset y if it not max height
const syStartDisplayCoords =
sy + (offScreenCanvasHeight - sHeight) / offScreenCanvasHeight;
const sWidthDisplayCoords = sWidth / offScreenCanvasWidth;
const sHeightDisplayCoords = sHeight / offScreenCanvasHeight;
return {
sxStartDisplayCoords,
syStartDisplayCoords,
sxEndDisplayCoords: sxStartDisplayCoords + sWidthDisplayCoords,
syEndDisplayCoords: syStartDisplayCoords + sHeightDisplayCoords,
sx,
sy,
sWidth,
sHeight,
};
}
/**
* @method _getViewportsAsArray Returns an array of all viewports
*
* @returns {Array} Array of viewports.
*/
private _getViewportsAsArray() {
return Array.from(this._viewports.values());
}
private _setViewportsToBeRenderedNextFrame(viewportIds: string[]) {
// Add the viewports to the set of flagged viewports
viewportIds.forEach((viewportId) => {
this._needsRender.add(viewportId);
});
// Render any flagged viewports
this._render();
}
/**
* Sets up animation frame if necessary
*/
private _render() {
// If we have viewports that need rendering and we have not already
// set the RAF callback to run on the next frame.
if (this._needsRender.size > 0 && this._animationFrameSet === false) {
this._animationFrameHandle = window.requestAnimationFrame(
this._renderFlaggedViewports
);
// Set the flag that we have already set up the next RAF call.
this._animationFrameSet = true;
}
}
/**
* Renders all viewports.
*/
private _renderFlaggedViewports = () => {
this._throwIfDestroyed();
if (!this.useCPURendering) {
this.performVtkDrawCall();
}
const viewports = this._getViewportsAsArray();
const eventDetailArray = [];
for (let i = 0; i < viewports.length; i++) {
const viewport = viewports[i];
if (this._needsRender.has(viewport.id)) {
const eventDetail =
this.renderViewportUsingCustomOrVtkPipeline(viewport);
eventDetailArray.push(eventDetail);
viewport.setRendered();
// This viewport has been rendered, we can remove it from the set
this._needsRender.delete(viewport.id);
// If there is nothing left that is flagged for rendering, stop the loop
if (this._needsRender.size === 0) {
break;
}
}
}
// allow RAF to be called again
this._animationFrameSet = false;
this._animationFrameHandle = null;
eventDetailArray.forEach((eventDetail) => {
// Very small viewports won't have an element
Iif (!eventDetail?.element) {
return;
}
triggerEvent(eventDetail.element, Events.IMAGE_RENDERED, eventDetail);
});
};
/**
* Performs the single `vtk.js` draw call which is used to render the offscreen
* canvas for vtk.js. This is a bulk rendering step for all Volume and Stack
* viewports when GPU rendering is available.
*/
private performVtkDrawCall() {
// Render all viewports under vtk.js' control.
const { offscreenMultiRenderWindow } = this;
const renderWindow = offscreenMultiRenderWindow.getRenderWindow();
const renderers = offscreenMultiRenderWindow.getRenderers();
Iif (!renderers.length) {
return;
}
for (let i = 0; i < renderers.length; i++) {
const { renderer, id } = renderers[i];
// Requesting viewports that need rendering to be rendered only
if (this._needsRender.has(id)) {
renderer.setDraw(true);
} else {
renderer.setDraw(false);
}
}
renderWindow.render();
// After redraw we set all renderers to not render until necessary
for (let i = 0; i < renderers.length; i++) {
renderers[i].renderer.setDraw(false);
}
}
/**
* Renders the given viewport
* using its proffered method.
*
* @param viewport - The viewport to render
*/
private renderViewportUsingCustomOrVtkPipeline(
viewport: IViewport
): EventTypes.ImageRenderedEventDetail[] {
let eventDetail;
// Rendering engines start having issues without at least two pixels
// in each direction
Iif (
viewport.sWidth < VIEWPORT_MIN_SIZE ||
viewport.sHeight < VIEWPORT_MIN_SIZE
) {
console.warn('Viewport is too small', viewport.sWidth, viewport.sHeight);
return;
}
if (viewportTypeUsesCustomRenderingPipeline(viewport.type) === true) {
eventDetail =
viewport.customRenderViewportToCanvas() as EventTypes.ImageRenderedEventDetail;
} else {
Iif (this.useCPURendering) {
throw new Error(
'GPU not available, and using a viewport with no custom render pipeline.'
);
}
const { offscreenMultiRenderWindow } = this;
const openGLRenderWindow =
offscreenMultiRenderWindow.getOpenGLRenderWindow();
const context = openGLRenderWindow.get3DContext();
const offScreenCanvas = context.canvas;
eventDetail = this._renderViewportFromVtkCanvasToOnscreenCanvas(
viewport,
offScreenCanvas
);
}
return eventDetail;
}
/**
* Renders a particular `Viewport`'s on screen canvas.
* @param viewport - The `Viewport` to render.
* @param offScreenCanvas - The offscreen canvas to render from.
*/
private _renderViewportFromVtkCanvasToOnscreenCanvas(
viewport: IViewport,
offScreenCanvas
): EventTypes.ImageRenderedEventDetail {
const {
element,
canvas,
sx,
sy,
sWidth,
sHeight,
id: viewportId,
renderingEngineId,
suppressEvents,
} = viewport;
const { width: dWidth, height: dHeight } = canvas;
const onScreenContext = canvas.getContext('2d');
onScreenContext.drawImage(
offScreenCanvas,
sx,
sy,
sWidth,
sHeight,
0, //dx
0, // dy
dWidth,
dHeight
);
return {
element,
suppressEvents,
viewportId,
renderingEngineId,
viewportStatus: viewport.viewportStatus,
};
}
/**
* Reset the viewport by removing the data attributes
* and clearing the context of draw. It also emits an element disabled event
*
* @param viewport - The `Viewport` to render.
*/
private _resetViewport(viewport: IViewport) {
const renderingEngineId = this.id;
const { element, canvas, id: viewportId } = viewport;
const eventDetail: EventTypes.ElementDisabledEventDetail = {
element,
viewportId,
renderingEngineId,
};
viewport.removeWidgets();
// Trigger first before removing the data attributes, as we need the enabled
// element to remove tools associated with the viewport
triggerEvent(eventTarget, Events.ELEMENT_DISABLED, eventDetail);
element.removeAttribute('data-viewport-uid');
element.removeAttribute('data-rendering-engine-uid');
// clear drawing
const context = canvas.getContext('2d');
context.clearRect(0, 0, canvas.width, canvas.height);
}
private _clearAnimationFrame() {
window.cancelAnimationFrame(this._animationFrameHandle);
this._needsRender.clear();
this._animationFrameSet = false;
this._animationFrameHandle = null;
}
/**
* Resets the `RenderingEngine`
*/
private _reset() {
const viewports = this._getViewportsAsArray();
viewports.forEach((viewport) => {
this._resetViewport(viewport);
});
this._clearAnimationFrame();
this._viewports = new Map();
}
/**
* Throws an error if trying to interact with the `RenderingEngine`
* instance after its `destroy` method has been called.
*/
private _throwIfDestroyed() {
Iif (this.hasBeenDestroyed) {
throw new Error(
'this.destroy() has been manually called to free up memory, can not longer use this instance. Instead make a new one.'
);
}
}
// debugging utils for offScreen canvas
_downloadOffScreenCanvas() {
const dataURL = this._debugRender();
_TEMPDownloadURI(dataURL);
}
// debugging utils for offScreen canvas
_debugRender(): void {
const { offscreenMultiRenderWindow } = this;
const renderWindow = offscreenMultiRenderWindow.getRenderWindow();
const renderers = offscreenMultiRenderWindow.getRenderers();
for (let i = 0; i < renderers.length; i++) {
renderers[i].renderer.setDraw(true);
}
renderWindow.render();
const openGLRenderWindow =
offscreenMultiRenderWindow.getOpenGLRenderWindow();
const context = openGLRenderWindow.get3DContext();
const offScreenCanvas = context.canvas;
const dataURL = offScreenCanvas.toDataURL();
this._getViewportsAsArray().forEach((viewport) => {
const { sx, sy, sWidth, sHeight } = viewport;
const canvas = <HTMLCanvasElement>viewport.canvas;
const { width: dWidth, height: dHeight } = canvas;
const onScreenContext = canvas.getContext('2d');
//sx, sy, sWidth, sHeight, dx, dy, dWidth, dHeight
onScreenContext.drawImage(
offScreenCanvas,
sx,
sy,
sWidth,
sHeight,
0, //dx
0, // dy
dWidth,
dHeight
);
});
return dataURL;
}
}
export default RenderingEngine;
// debugging utils for offScreen canvas
function _TEMPDownloadURI(uri) {
const link = document.createElement('a');
link.download = 'viewport.png';
link.href = uri;
document.body.appendChild(link);
link.click();
document.body.removeChild(link);
}
|