大屏添加cesium

public/sdk/three/jsm/renderers/common/BufferUtils.js

@@ -0,0 +1,33 @@
+import { GPU_CHUNK_BYTES } from './Constants.js';
+
+function getFloatLength( floatLength ) {
+
+	// ensure chunk size alignment (STD140 layout)
+
+	return floatLength + ( ( GPU_CHUNK_BYTES - ( floatLength % GPU_CHUNK_BYTES ) ) % GPU_CHUNK_BYTES );
+
+}
+
+function getVectorLength( count, vectorLength = 4 ) {
+
+	const strideLength = getStrideLength( vectorLength );
+
+	const floatLength = strideLength * count;
+
+	return getFloatLength( floatLength );
+
+}
+
+function getStrideLength( vectorLength ) {
+
+	const strideLength = 4;
+
+	return vectorLength + ( ( strideLength - ( vectorLength % strideLength ) ) % strideLength );
+
+}
+
+export {
+	getFloatLength,
+	getVectorLength,
+	getStrideLength
+};