scratch-render
Version:
WebGL Renderer for Scratch 3.0
735 lines (660 loc) • 28.3 kB
JavaScript
const twgl = require('twgl.js');
const Rectangle = require('./Rectangle');
const RenderConstants = require('./RenderConstants');
const ShaderManager = require('./ShaderManager');
const Skin = require('./Skin');
const EffectTransform = require('./EffectTransform');
const log = require('./util/log');
/**
* An internal workspace for calculating texture locations from world vectors
* this is REUSED for memory conservation reasons
* @type {twgl.v3}
*/
const __isTouchingPosition = twgl.v3.create();
const FLOATING_POINT_ERROR_ALLOWANCE = 1e-6;
/**
* Convert a scratch space location into a texture space float. Uses the
* internal __isTouchingPosition as a return value, so this should be copied
* if you ever need to get two local positions and store both. Requires that
* the drawable inverseMatrix is up to date.
*
* @param {Drawable} drawable The drawable to get the inverse matrix and uniforms from
* @param {twgl.v3} vec [x,y] scratch space vector
* @return {twgl.v3} [x,y] texture space float vector - transformed by effects and matrix
*/
const getLocalPosition = (drawable, vec) => {
// Transfrom from world coordinates to Drawable coordinates.
const localPosition = __isTouchingPosition;
const v0 = vec[0];
const v1 = vec[1];
const m = drawable._inverseMatrix;
// var v2 = v[2];
const d = (v0 * m[3]) + (v1 * m[7]) + m[15];
// The RenderWebGL quad flips the texture's X axis. So rendered bottom
// left is 1, 0 and the top right is 0, 1. Flip the X axis so
// localPosition matches that transformation.
localPosition[0] = 0.5 - (((v0 * m[0]) + (v1 * m[4]) + m[12]) / d);
localPosition[1] = (((v0 * m[1]) + (v1 * m[5]) + m[13]) / d) + 0.5;
// Fix floating point issues near 0. Filed https://github.com/LLK/scratch-render/issues/688 that
// they're happening in the first place.
// TODO: Check if this can be removed after render pull 479 is merged
if (Math.abs(localPosition[0]) < FLOATING_POINT_ERROR_ALLOWANCE) localPosition[0] = 0;
if (Math.abs(localPosition[1]) < FLOATING_POINT_ERROR_ALLOWANCE) localPosition[1] = 0;
// Apply texture effect transform if the localPosition is within the drawable's space,
// and any effects are currently active.
if (drawable.enabledEffects !== 0 &&
(localPosition[0] >= 0 && localPosition[0] < 1) &&
(localPosition[1] >= 0 && localPosition[1] < 1)) {
EffectTransform.transformPoint(drawable, localPosition, localPosition);
}
return localPosition;
};
class Drawable {
/**
* An object which can be drawn by the renderer.
* @todo double-buffer all rendering state (position, skin, effects, etc.)
* @param {!int} id - This Drawable's unique ID.
* @constructor
*/
constructor (id) {
/** @type {!int} */
this._id = id;
/**
* The uniforms to be used by the vertex and pixel shaders.
* Some of these are used by other parts of the renderer as well.
* @type {Object.<string,*>}
* @private
*/
this._uniforms = {
/**
* The model matrix, to concat with projection at draw time.
* @type {module:twgl/m4.Mat4}
*/
u_modelMatrix: twgl.m4.identity(),
/**
* The color to use in the silhouette draw mode.
* @type {Array<number>}
*/
u_silhouetteColor: Drawable.color4fFromID(this._id)
};
// Effect values are uniforms too
const numEffects = ShaderManager.EFFECTS.length;
for (let index = 0; index < numEffects; ++index) {
const effectName = ShaderManager.EFFECTS[index];
const effectInfo = ShaderManager.EFFECT_INFO[effectName];
const converter = effectInfo.converter;
this._uniforms[effectInfo.uniformName] = converter(0);
}
this._position = twgl.v3.create(0, 0);
this._scale = twgl.v3.create(100, 100);
this._direction = 90;
this._transformDirty = true;
this._rotationMatrix = twgl.m4.identity();
this._rotationTransformDirty = true;
this._rotationAdjusted = twgl.v3.create();
this._rotationCenterDirty = true;
this._skinScale = twgl.v3.create(0, 0, 0);
this._skinScaleDirty = true;
this._inverseMatrix = twgl.m4.identity();
this._inverseTransformDirty = true;
this._visible = true;
/** A bitmask identifying which effects are currently in use.
* @readonly
* @type {int} */
this.enabledEffects = 0;
/** @todo move convex hull functionality, maybe bounds functionality overall, to Skin classes */
this._convexHullPoints = null;
this._convexHullDirty = true;
// The precise bounding box will be from the transformed convex hull points,
// so initialize the array of transformed hull points in setConvexHullPoints.
// Initializing it once per convex hull recalculation avoids unnecessary creation of twgl.v3 objects.
this._transformedHullPoints = null;
this._transformedHullDirty = true;
this._skinWasAltered = this._skinWasAltered.bind(this);
this.isTouching = this._isTouchingNever;
}
/**
* Dispose of this Drawable. Do not use it after calling this method.
*/
dispose () {
// Use the setter: disconnect events
this.skin = null;
}
/**
* Mark this Drawable's transform as dirty.
* It will be recalculated next time it's needed.
*/
setTransformDirty () {
this._transformDirty = true;
this._inverseTransformDirty = true;
this._transformedHullDirty = true;
}
/**
* @returns {number} The ID for this Drawable.
*/
get id () {
return this._id;
}
/**
* @returns {Skin} the current skin for this Drawable.
*/
get skin () {
return this._skin;
}
/**
* @param {Skin} newSkin - A new Skin for this Drawable.
*/
set skin (newSkin) {
if (this._skin !== newSkin) {
if (this._skin) {
this._skin.removeListener(Skin.Events.WasAltered, this._skinWasAltered);
}
this._skin = newSkin;
if (this._skin) {
this._skin.addListener(Skin.Events.WasAltered, this._skinWasAltered);
}
this._skinWasAltered();
}
}
/**
* @returns {Array<number>} the current scaling percentages applied to this Drawable. [100,100] is normal size.
*/
get scale () {
return [this._scale[0], this._scale[1]];
}
/**
* @returns {object.<string, *>} the shader uniforms to be used when rendering this Drawable.
*/
getUniforms () {
if (this._transformDirty) {
this._calculateTransform();
}
return this._uniforms;
}
/**
* @returns {boolean} whether this Drawable is visible.
*/
getVisible () {
return this._visible;
}
/**
* Update the position if it is different. Marks the transform as dirty.
* @param {Array.<number>} position A new position.
*/
updatePosition (position) {
if (this._position[0] !== position[0] ||
this._position[1] !== position[1]) {
this._position[0] = Math.round(position[0]);
this._position[1] = Math.round(position[1]);
this.setTransformDirty();
}
}
/**
* Update the direction if it is different. Marks the transform as dirty.
* @param {number} direction A new direction.
*/
updateDirection (direction) {
if (this._direction !== direction) {
this._direction = direction;
this._rotationTransformDirty = true;
this.setTransformDirty();
}
}
/**
* Update the scale if it is different. Marks the transform as dirty.
* @param {Array.<number>} scale A new scale.
*/
updateScale (scale) {
if (this._scale[0] !== scale[0] ||
this._scale[1] !== scale[1]) {
this._scale[0] = scale[0];
this._scale[1] = scale[1];
this._rotationCenterDirty = true;
this._skinScaleDirty = true;
this.setTransformDirty();
}
}
/**
* Update visibility if it is different. Marks the convex hull as dirty.
* @param {boolean} visible A new visibility state.
*/
updateVisible (visible) {
if (this._visible !== visible) {
this._visible = visible;
this.setConvexHullDirty();
}
}
/**
* Update an effect. Marks the convex hull as dirty if the effect changes shape.
* @param {string} effectName The name of the effect.
* @param {number} rawValue A new effect value.
*/
updateEffect (effectName, rawValue) {
const effectInfo = ShaderManager.EFFECT_INFO[effectName];
if (rawValue) {
this.enabledEffects |= effectInfo.mask;
} else {
this.enabledEffects &= ~effectInfo.mask;
}
const converter = effectInfo.converter;
this._uniforms[effectInfo.uniformName] = converter(rawValue);
if (effectInfo.shapeChanges) {
this.setConvexHullDirty();
}
}
/**
* Update the position, direction, scale, or effect properties of this Drawable.
* @deprecated Use specific update* methods instead.
* @param {object.<string,*>} properties The new property values to set.
*/
updateProperties (properties) {
if ('position' in properties) {
this.updatePosition(properties.position);
}
if ('direction' in properties) {
this.updateDirection(properties.direction);
}
if ('scale' in properties) {
this.updateScale(properties.scale);
}
if ('visible' in properties) {
this.updateVisible(properties.visible);
}
const numEffects = ShaderManager.EFFECTS.length;
for (let index = 0; index < numEffects; ++index) {
const effectName = ShaderManager.EFFECTS[index];
if (effectName in properties) {
this.updateEffect(effectName, properties[effectName]);
}
}
}
/**
* Calculate the transform to use when rendering this Drawable.
* @private
*/
_calculateTransform () {
if (this._rotationTransformDirty) {
const rotation = (270 - this._direction) * Math.PI / 180;
// Calling rotationZ sets the destination matrix to a rotation
// around the Z axis setting matrix components 0, 1, 4 and 5 with
// cosine and sine values of the rotation.
// twgl.m4.rotationZ(rotation, this._rotationMatrix);
// twgl assumes the last value set to the matrix was anything.
// Drawable knows, it was another rotationZ matrix, so we can skip
// assigning the values that will never change.
const c = Math.cos(rotation);
const s = Math.sin(rotation);
this._rotationMatrix[0] = c;
this._rotationMatrix[1] = s;
// this._rotationMatrix[2] = 0;
// this._rotationMatrix[3] = 0;
this._rotationMatrix[4] = -s;
this._rotationMatrix[5] = c;
// this._rotationMatrix[6] = 0;
// this._rotationMatrix[7] = 0;
// this._rotationMatrix[8] = 0;
// this._rotationMatrix[9] = 0;
// this._rotationMatrix[10] = 1;
// this._rotationMatrix[11] = 0;
// this._rotationMatrix[12] = 0;
// this._rotationMatrix[13] = 0;
// this._rotationMatrix[14] = 0;
// this._rotationMatrix[15] = 1;
this._rotationTransformDirty = false;
}
// Adjust rotation center relative to the skin.
if (this._rotationCenterDirty && this.skin !== null) {
// twgl version of the following in function work.
// let rotationAdjusted = twgl.v3.subtract(
// this.skin.rotationCenter,
// twgl.v3.divScalar(this.skin.size, 2, this._rotationAdjusted),
// this._rotationAdjusted
// );
// rotationAdjusted = twgl.v3.multiply(
// rotationAdjusted, this._scale, rotationAdjusted
// );
// rotationAdjusted = twgl.v3.divScalar(
// rotationAdjusted, 100, rotationAdjusted
// );
// rotationAdjusted[1] *= -1; // Y flipped to Scratch coordinate.
// rotationAdjusted[2] = 0; // Z coordinate is 0.
// Locally assign rotationCenter and skinSize to keep from having
// the Skin getter properties called twice while locally assigning
// their components for readability.
const rotationCenter = this.skin.rotationCenter;
const skinSize = this.skin.size;
const center0 = rotationCenter[0];
const center1 = rotationCenter[1];
const skinSize0 = skinSize[0];
const skinSize1 = skinSize[1];
const scale0 = this._scale[0];
const scale1 = this._scale[1];
const rotationAdjusted = this._rotationAdjusted;
rotationAdjusted[0] = (center0 - (skinSize0 / 2)) * scale0 / 100;
rotationAdjusted[1] = ((center1 - (skinSize1 / 2)) * scale1 / 100) * -1;
// rotationAdjusted[2] = 0;
this._rotationCenterDirty = false;
}
if (this._skinScaleDirty && this.skin !== null) {
// twgl version of the following in function work.
// const scaledSize = twgl.v3.divScalar(
// twgl.v3.multiply(this.skin.size, this._scale),
// 100
// );
// // was NaN because the vectors have only 2 components.
// scaledSize[2] = 0;
// Locally assign skinSize to keep from having the Skin getter
// properties called twice.
const skinSize = this.skin.size;
const scaledSize = this._skinScale;
scaledSize[0] = skinSize[0] * this._scale[0] / 100;
scaledSize[1] = skinSize[1] * this._scale[1] / 100;
// scaledSize[2] = 0;
this._skinScaleDirty = false;
}
const modelMatrix = this._uniforms.u_modelMatrix;
// twgl version of the following in function work.
// twgl.m4.identity(modelMatrix);
// twgl.m4.translate(modelMatrix, this._position, modelMatrix);
// twgl.m4.multiply(modelMatrix, this._rotationMatrix, modelMatrix);
// twgl.m4.translate(modelMatrix, this._rotationAdjusted, modelMatrix);
// twgl.m4.scale(modelMatrix, scaledSize, modelMatrix);
// Drawable configures a 3D matrix for drawing in WebGL, but most values
// will never be set because the inputs are on the X and Y position axis
// and the Z rotation axis. Drawable can bring the work inside
// _calculateTransform and greatly reduce the ammount of math and array
// assignments needed.
const scale0 = this._skinScale[0];
const scale1 = this._skinScale[1];
const rotation00 = this._rotationMatrix[0];
const rotation01 = this._rotationMatrix[1];
const rotation10 = this._rotationMatrix[4];
const rotation11 = this._rotationMatrix[5];
const adjusted0 = this._rotationAdjusted[0];
const adjusted1 = this._rotationAdjusted[1];
const position0 = this._position[0];
const position1 = this._position[1];
// Commented assignments show what the values are when the matrix was
// instantiated. Those values will never change so they do not need to
// be reassigned.
modelMatrix[0] = scale0 * rotation00;
modelMatrix[1] = scale0 * rotation01;
// modelMatrix[2] = 0;
// modelMatrix[3] = 0;
modelMatrix[4] = scale1 * rotation10;
modelMatrix[5] = scale1 * rotation11;
// modelMatrix[6] = 0;
// modelMatrix[7] = 0;
// modelMatrix[8] = 0;
// modelMatrix[9] = 0;
// modelMatrix[10] = 1;
// modelMatrix[11] = 0;
modelMatrix[12] = (rotation00 * adjusted0) + (rotation10 * adjusted1) + position0;
modelMatrix[13] = (rotation01 * adjusted0) + (rotation11 * adjusted1) + position1;
// modelMatrix[14] = 0;
// modelMatrix[15] = 1;
this._transformDirty = false;
}
/**
* Whether the Drawable needs convex hull points provided by the renderer.
* @return {boolean} True when no convex hull known, or it's dirty.
*/
needsConvexHullPoints () {
return !this._convexHullPoints || this._convexHullDirty || this._convexHullPoints.length === 0;
}
/**
* Set the convex hull to be dirty.
* Do this whenever the Drawable's shape has possibly changed.
*/
setConvexHullDirty () {
this._convexHullDirty = true;
}
/**
* Set the convex hull points for the Drawable.
* @param {Array<Array<number>>} points Convex hull points, as [[x, y], ...]
*/
setConvexHullPoints (points) {
this._convexHullPoints = points;
this._convexHullDirty = false;
// Re-create the "transformed hull points" array.
// We only do this when the hull points change to avoid unnecessary allocations and GC.
this._transformedHullPoints = [];
for (let i = 0; i < points.length; i++) {
this._transformedHullPoints.push(twgl.v3.create());
}
this._transformedHullDirty = true;
}
/**
* @function
* @name isTouching
* Check if the world position touches the skin.
* The caller is responsible for ensuring this drawable's inverse matrix & its skin's silhouette are up-to-date.
* @see updateCPURenderAttributes
* @param {twgl.v3} vec World coordinate vector.
* @return {boolean} True if the world position touches the skin.
*/
// `updateCPURenderAttributes` sets this Drawable instance's `isTouching` method
// to one of the following three functions:
// If this drawable has no skin, set it to `_isTouchingNever`.
// Otherwise, if this drawable uses nearest-neighbor scaling at its current scale, set it to `_isTouchingNearest`.
// Otherwise, set it to `_isTouchingLinear`.
// This allows several checks to be moved from the `isTouching` function to `updateCPURenderAttributes`.
// eslint-disable-next-line no-unused-vars
_isTouchingNever (vec) {
return false;
}
_isTouchingNearest (vec) {
return this.skin.isTouchingNearest(getLocalPosition(this, vec));
}
_isTouchingLinear (vec) {
return this.skin.isTouchingLinear(getLocalPosition(this, vec));
}
/**
* Get the precise bounds for a Drawable.
* This function applies the transform matrix to the known convex hull,
* and then finds the minimum box along the axes.
* Before calling this, ensure the renderer has updated convex hull points.
* @param {?Rectangle} result optional destination for bounds calculation
* @return {!Rectangle} Bounds for a tight box around the Drawable.
*/
getBounds (result) {
if (this.needsConvexHullPoints()) {
throw new Error('Needs updated convex hull points before bounds calculation.');
}
if (this._transformDirty) {
this._calculateTransform();
}
const transformedHullPoints = this._getTransformedHullPoints();
// Search through transformed points to generate box on axes.
result = result || new Rectangle();
result.initFromPointsAABB(transformedHullPoints);
return result;
}
/**
* Get the precise bounds for the upper 8px slice of the Drawable.
* Used for calculating where to position a text bubble.
* Before calling this, ensure the renderer has updated convex hull points.
* @param {?Rectangle} result optional destination for bounds calculation
* @return {!Rectangle} Bounds for a tight box around a slice of the Drawable.
*/
getBoundsForBubble (result) {
if (this.needsConvexHullPoints()) {
throw new Error('Needs updated convex hull points before bubble bounds calculation.');
}
if (this._transformDirty) {
this._calculateTransform();
}
const slice = 8; // px, how tall the top slice to measure should be.
const transformedHullPoints = this._getTransformedHullPoints();
const maxY = Math.max.apply(null, transformedHullPoints.map(p => p[1]));
const filteredHullPoints = transformedHullPoints.filter(p => p[1] > maxY - slice);
// Search through filtered points to generate box on axes.
result = result || new Rectangle();
result.initFromPointsAABB(filteredHullPoints);
return result;
}
/**
* Get the rough axis-aligned bounding box for the Drawable.
* Calculated by transforming the skin's bounds.
* Note that this is less precise than the box returned by `getBounds`,
* which is tightly snapped to account for a Drawable's transparent regions.
* `getAABB` returns a much less accurate bounding box, but will be much
* faster to calculate so may be desired for quick checks/optimizations.
* @param {?Rectangle} result optional destination for bounds calculation
* @return {!Rectangle} Rough axis-aligned bounding box for Drawable.
*/
getAABB (result) {
if (this._transformDirty) {
this._calculateTransform();
}
const tm = this._uniforms.u_modelMatrix;
result = result || new Rectangle();
result.initFromModelMatrix(tm);
return result;
}
/**
* Return the best Drawable bounds possible without performing graphics queries.
* I.e., returns the tight bounding box when the convex hull points are already
* known, but otherwise return the rough AABB of the Drawable.
* @param {?Rectangle} result optional destination for bounds calculation
* @return {!Rectangle} Bounds for the Drawable.
*/
getFastBounds (result) {
if (!this.needsConvexHullPoints()) {
return this.getBounds(result);
}
return this.getAABB(result);
}
/**
* Transform all the convex hull points by the current Drawable's
* transform. This allows us to skip recalculating the convex hull
* for many Drawable updates, including translation, rotation, scaling.
* @return {!Array.<!Array.number>} Array of glPoints which are Array<x, y>
* @private
*/
_getTransformedHullPoints () {
if (!this._transformedHullDirty) {
return this._transformedHullPoints;
}
const projection = twgl.m4.ortho(-1, 1, -1, 1, -1, 1);
const skinSize = this.skin.size;
const halfXPixel = 1 / skinSize[0] / 2;
const halfYPixel = 1 / skinSize[1] / 2;
const tm = twgl.m4.multiply(this._uniforms.u_modelMatrix, projection);
for (let i = 0; i < this._convexHullPoints.length; i++) {
const point = this._convexHullPoints[i];
const dstPoint = this._transformedHullPoints[i];
dstPoint[0] = 0.5 + (-point[0] / skinSize[0]) - halfXPixel;
dstPoint[1] = (point[1] / skinSize[1]) - 0.5 + halfYPixel;
twgl.m4.transformPoint(tm, dstPoint, dstPoint);
}
this._transformedHullDirty = false;
return this._transformedHullPoints;
}
/**
* Update the transform matrix and calculate it's inverse for collision
* and local texture position purposes.
*/
updateMatrix () {
if (this._transformDirty) {
this._calculateTransform();
}
// Get the inverse of the model matrix or update it.
if (this._inverseTransformDirty) {
const inverse = this._inverseMatrix;
twgl.m4.copy(this._uniforms.u_modelMatrix, inverse);
// The normal matrix uses a z scaling of 0 causing model[10] to be
// 0. Getting a 4x4 inverse is impossible without a scaling in x, y,
// and z.
inverse[10] = 1;
twgl.m4.inverse(inverse, inverse);
this._inverseTransformDirty = false;
}
}
/**
* Update everything necessary to render this drawable on the CPU.
*/
updateCPURenderAttributes () {
this.updateMatrix();
// CPU rendering always occurs at the "native" size, so no need to scale up this._scale
if (this.skin) {
this.skin.updateSilhouette(this._scale);
if (this.skin.useNearest(this._scale, this)) {
this.isTouching = this._isTouchingNearest;
} else {
this.isTouching = this._isTouchingLinear;
}
} else {
log.warn(`Could not find skin for drawable with id: ${this._id}`);
this.isTouching = this._isTouchingNever;
}
}
/**
* Respond to an internal change in the current Skin.
* @private
*/
_skinWasAltered () {
this._rotationCenterDirty = true;
this._skinScaleDirty = true;
this.setConvexHullDirty();
this.setTransformDirty();
}
/**
* Calculate a color to represent the given ID number. At least one component of
* the resulting color will be non-zero if the ID is not RenderConstants.ID_NONE.
* @param {int} id The ID to convert.
* @returns {Array<number>} An array of [r,g,b,a], each component in the range [0,1].
*/
static color4fFromID (id) {
id -= RenderConstants.ID_NONE;
const r = ((id >> 0) & 255) / 255.0;
const g = ((id >> 8) & 255) / 255.0;
const b = ((id >> 16) & 255) / 255.0;
return [r, g, b, 1.0];
}
/**
* Calculate the ID number represented by the given color. If all components of
* the color are zero, the result will be RenderConstants.ID_NONE; otherwise the result
* will be a valid ID.
* @param {int} r The red value of the color, in the range [0,255].
* @param {int} g The green value of the color, in the range [0,255].
* @param {int} b The blue value of the color, in the range [0,255].
* @returns {int} The ID represented by that color.
*/
static color3bToID (r, g, b) {
let id;
id = (r & 255) << 0;
id |= (g & 255) << 8;
id |= (b & 255) << 16;
return id + RenderConstants.ID_NONE;
}
/**
* Sample a color from a drawable's texture.
* The caller is responsible for ensuring this drawable's inverse matrix & its skin's silhouette are up-to-date.
* @see updateCPURenderAttributes
* @param {twgl.v3} vec The scratch space [x,y] vector
* @param {Drawable} drawable The drawable to sample the texture from
* @param {Uint8ClampedArray} dst The "color4b" representation of the texture at point.
* @param {number} [effectMask] A bitmask for which effects to use. Optional.
* @returns {Uint8ClampedArray} The dst object filled with the color4b
*/
static sampleColor4b (vec, drawable, dst, effectMask) {
const localPosition = getLocalPosition(drawable, vec);
if (localPosition[0] < 0 || localPosition[1] < 0 ||
localPosition[0] > 1 || localPosition[1] > 1) {
dst[0] = 0;
dst[1] = 0;
dst[2] = 0;
dst[3] = 0;
return dst;
}
const textColor =
// commenting out to only use nearest for now
// drawable.skin.useNearest(drawable._scale, drawable) ?
drawable.skin._silhouette.colorAtNearest(localPosition, dst);
// : drawable.skin._silhouette.colorAtLinear(localPosition, dst);
if (drawable.enabledEffects === 0) return textColor;
return EffectTransform.transformColor(drawable, textColor, effectMask);
}
}
module.exports = Drawable;