我花了一些时间(目前用于未索引的三角形列表),这很容易。
var wireframe_pos = new Float32Array( positionArray.length * 2 );
for( var ii = 0; ii < positionArray.length; ii += 9 ) {
wireframe_pos[ ii * 2 ] = positionArray[ ii ];
wireframe_pos[ ii * 2 + 1 ] = positionArray[ ii + 1 ];
wireframe_pos[ ii * 2 + 2 ] = positionArray[ ii + 2 ];
wireframe_pos[ ii * 2 + 3 ] = positionArray[ ii + 3 ];
wireframe_pos[ ii * 2 + 4 ] = positionArray[ ii + 4 ];
wireframe_pos[ ii * 2 + 5 ] = positionArray[ ii + 5 ];
wireframe_pos[ ii * 2 + 6 ] = positionArray[ ii + 3 ];
wireframe_pos[ ii * 2 + 7 ] = positionArray[ ii + 4 ];
wireframe_pos[ ii * 2 + 8 ] = positionArray[ ii + 5 ];
wireframe_pos[ ii * 2 + 9 ] = positionArray[ ii + 6 ];
wireframe_pos[ ii * 2 + 10 ] = positionArray[ ii + 7 ];
wireframe_pos[ ii * 2 + 11 ] = positionArray[ ii + 8 ];
wireframe_pos[ ii * 2 + 12 ] = positionArray[ ii + 6 ];
wireframe_pos[ ii * 2 + 13 ] = positionArray[ ii + 7 ];
wireframe_pos[ ii * 2 + 14 ] = positionArray[ ii + 8 ];
wireframe_pos[ ii * 2 + 15 ] = positionArray[ ii ];
wireframe_pos[ ii * 2 + 16 ] = positionArray[ ii + 1 ];
wireframe_pos[ ii * 2 + 17 ] = positionArray[ ii + 2 ];
}
attributes[ "position" ] = { itemSize: 3, array: wireframe_pos, numItems: wireframe_pos.length };
虽然老实说,我对这个解决方案并不完全满意,因为位置数组的大小是原始数组的两倍。感觉太重了。对更好的方法有什么建议吗?