Initial commit

HTML/ThreeJS/node_modules/three/src/animation/PropertyMixer.js

@@ -0,0 +1,318 @@
+import { Quaternion } from '../math/Quaternion.js';
+
+class PropertyMixer {
+
+	constructor( binding, typeName, valueSize ) {
+
+		this.binding = binding;
+		this.valueSize = valueSize;
+
+		let mixFunction,
+			mixFunctionAdditive,
+			setIdentity;
+
+		// buffer layout: [ incoming | accu0 | accu1 | orig | addAccu | (optional work) ]
+		//
+		// interpolators can use .buffer as their .result
+		// the data then goes to 'incoming'
+		//
+		// 'accu0' and 'accu1' are used frame-interleaved for
+		// the cumulative result and are compared to detect
+		// changes
+		//
+		// 'orig' stores the original state of the property
+		//
+		// 'add' is used for additive cumulative results
+		//
+		// 'work' is optional and is only present for quaternion types. It is used
+		// to store intermediate quaternion multiplication results
+
+		switch ( typeName ) {
+
+			case 'quaternion':
+				mixFunction = this._slerp;
+				mixFunctionAdditive = this._slerpAdditive;
+				setIdentity = this._setAdditiveIdentityQuaternion;
+
+				this.buffer = new Float64Array( valueSize * 6 );
+				this._workIndex = 5;
+				break;
+
+			case 'string':
+			case 'bool':
+				mixFunction = this._select;
+
+				// Use the regular mix function and for additive on these types,
+				// additive is not relevant for non-numeric types
+				mixFunctionAdditive = this._select;
+
+				setIdentity = this._setAdditiveIdentityOther;
+
+				this.buffer = new Array( valueSize * 5 );
+				break;
+
+			default:
+				mixFunction = this._lerp;
+				mixFunctionAdditive = this._lerpAdditive;
+				setIdentity = this._setAdditiveIdentityNumeric;
+
+				this.buffer = new Float64Array( valueSize * 5 );
+
+		}
+
+		this._mixBufferRegion = mixFunction;
+		this._mixBufferRegionAdditive = mixFunctionAdditive;
+		this._setIdentity = setIdentity;
+		this._origIndex = 3;
+		this._addIndex = 4;
+
+		this.cumulativeWeight = 0;
+		this.cumulativeWeightAdditive = 0;
+
+		this.useCount = 0;
+		this.referenceCount = 0;
+
+	}
+
+	// accumulate data in the 'incoming' region into 'accu<i>'
+	accumulate( accuIndex, weight ) {
+
+		// note: happily accumulating nothing when weight = 0, the caller knows
+		// the weight and shouldn't have made the call in the first place
+
+		const buffer = this.buffer,
+			stride = this.valueSize,
+			offset = accuIndex * stride + stride;
+
+		let currentWeight = this.cumulativeWeight;
+
+		if ( currentWeight === 0 ) {
+
+			// accuN := incoming * weight
+
+			for ( let i = 0; i !== stride; ++ i ) {
+
+				buffer[ offset + i ] = buffer[ i ];
+
+			}
+
+			currentWeight = weight;
+
+		} else {
+
+			// accuN := accuN + incoming * weight
+
+			currentWeight += weight;
+			const mix = weight / currentWeight;
+			this._mixBufferRegion( buffer, offset, 0, mix, stride );
+
+		}
+
+		this.cumulativeWeight = currentWeight;
+
+	}
+
+	// accumulate data in the 'incoming' region into 'add'
+	accumulateAdditive( weight ) {
+
+		const buffer = this.buffer,
+			stride = this.valueSize,
+			offset = stride * this._addIndex;
+
+		if ( this.cumulativeWeightAdditive === 0 ) {
+
+			// add = identity
+
+			this._setIdentity();
+
+		}
+
+		// add := add + incoming * weight
+
+		this._mixBufferRegionAdditive( buffer, offset, 0, weight, stride );
+		this.cumulativeWeightAdditive += weight;
+
+	}
+
+	// apply the state of 'accu<i>' to the binding when accus differ
+	apply( accuIndex ) {
+
+		const stride = this.valueSize,
+			buffer = this.buffer,
+			offset = accuIndex * stride + stride,
+
+			weight = this.cumulativeWeight,
+			weightAdditive = this.cumulativeWeightAdditive,
+
+			binding = this.binding;
+
+		this.cumulativeWeight = 0;
+		this.cumulativeWeightAdditive = 0;
+
+		if ( weight < 1 ) {
+
+			// accuN := accuN + original * ( 1 - cumulativeWeight )
+
+			const originalValueOffset = stride * this._origIndex;
+
+			this._mixBufferRegion(
+				buffer, offset, originalValueOffset, 1 - weight, stride );
+
+		}
+
+		if ( weightAdditive > 0 ) {
+
+			// accuN := accuN + additive accuN
+
+			this._mixBufferRegionAdditive( buffer, offset, this._addIndex * stride, 1, stride );
+
+		}
+
+		for ( let i = stride, e = stride + stride; i !== e; ++ i ) {
+
+			if ( buffer[ i ] !== buffer[ i + stride ] ) {
+
+				// value has changed -> update scene graph
+
+				binding.setValue( buffer, offset );
+				break;
+
+			}
+
+		}
+
+	}
+
+	// remember the state of the bound property and copy it to both accus
+	saveOriginalState() {
+
+		const binding = this.binding;
+
+		const buffer = this.buffer,
+			stride = this.valueSize,
+
+			originalValueOffset = stride * this._origIndex;
+
+		binding.getValue( buffer, originalValueOffset );
+
+		// accu[0..1] := orig -- initially detect changes against the original
+		for ( let i = stride, e = originalValueOffset; i !== e; ++ i ) {
+
+			buffer[ i ] = buffer[ originalValueOffset + ( i % stride ) ];
+
+		}
+
+		// Add to identity for additive
+		this._setIdentity();
+
+		this.cumulativeWeight = 0;
+		this.cumulativeWeightAdditive = 0;
+
+	}
+
+	// apply the state previously taken via 'saveOriginalState' to the binding
+	restoreOriginalState() {
+
+		const originalValueOffset = this.valueSize * 3;
+		this.binding.setValue( this.buffer, originalValueOffset );
+
+	}
+
+	_setAdditiveIdentityNumeric() {
+
+		const startIndex = this._addIndex * this.valueSize;
+		const endIndex = startIndex + this.valueSize;
+
+		for ( let i = startIndex; i < endIndex; i ++ ) {
+
+			this.buffer[ i ] = 0;
+
+		}
+
+	}
+
+	_setAdditiveIdentityQuaternion() {
+
+		this._setAdditiveIdentityNumeric();
+		this.buffer[ this._addIndex * this.valueSize + 3 ] = 1;
+
+	}
+
+	_setAdditiveIdentityOther() {
+
+		const startIndex = this._origIndex * this.valueSize;
+		const targetIndex = this._addIndex * this.valueSize;
+
+		for ( let i = 0; i < this.valueSize; i ++ ) {
+
+			this.buffer[ targetIndex + i ] = this.buffer[ startIndex + i ];
+
+		}
+
+	}
+
+
+	// mix functions
+
+	_select( buffer, dstOffset, srcOffset, t, stride ) {
+
+		if ( t >= 0.5 ) {
+
+			for ( let i = 0; i !== stride; ++ i ) {
+
+				buffer[ dstOffset + i ] = buffer[ srcOffset + i ];
+
+			}
+
+		}
+
+	}
+
+	_slerp( buffer, dstOffset, srcOffset, t ) {
+
+		Quaternion.slerpFlat( buffer, dstOffset, buffer, dstOffset, buffer, srcOffset, t );
+
+	}
+
+	_slerpAdditive( buffer, dstOffset, srcOffset, t, stride ) {
+
+		const workOffset = this._workIndex * stride;
+
+		// Store result in intermediate buffer offset
+		Quaternion.multiplyQuaternionsFlat( buffer, workOffset, buffer, dstOffset, buffer, srcOffset );
+
+		// Slerp to the intermediate result
+		Quaternion.slerpFlat( buffer, dstOffset, buffer, dstOffset, buffer, workOffset, t );
+
+	}
+
+	_lerp( buffer, dstOffset, srcOffset, t, stride ) {
+
+		const s = 1 - t;
+
+		for ( let i = 0; i !== stride; ++ i ) {
+
+			const j = dstOffset + i;
+
+			buffer[ j ] = buffer[ j ] * s + buffer[ srcOffset + i ] * t;
+
+		}
+
+	}
+
+	_lerpAdditive( buffer, dstOffset, srcOffset, t, stride ) {
+
+		for ( let i = 0; i !== stride; ++ i ) {
+
+			const j = dstOffset + i;
+
+			buffer[ j ] = buffer[ j ] + buffer[ srcOffset + i ] * t;
+
+		}
+
+	}
+
+}
+
+
+export { PropertyMixer };