Threejs BufferGeometry-用其他紋理渲染一些面孔

Question

我有這樣的輸出日期：

geom[0] = {

texturesindexT: new Int16Array([0,1,2,3]),
texturesindexS: new Int16Array([-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,...]),

materialsindexT: new Int16Array([-1,-1,-1,-1]),
materialsindexS: new Int16Array([-1,0,1,2,3,4,5,0,6,2,7,8,-1,0,...]),

startIndicesT: new Uint32Array([0,288,606,897,1380]),
startIndicesS: new Uint32Array([1380,1431,1479,1485,1497,1515,1659,...]),

m_indices: new Uint16Array([0,1,2,3,0,2,4,2,5,4,6,2,7,3,2,8,9,10,...]),

m_vertices: new Float32Array([-81.93996,25.7185,-85.53822,-81.93996,...]),

m_normals: new Float32Array([-0.004215205,0.9999894,-0.001817489,-0.004215205,...]),

m_texCoords: new Float32Array([0,0.04391319,0,0.2671326,0.009521127,0.03514284,...]),

}

var textures = new Array("-1_-1/t0.jpg","-1_-1/t1.jpg","-1_-1/t2.jpg",...);

數據用於索引，頂點和法線緩沖區，但是必須使用其他紋理和Maretials渲染部分。

我試圖從索引，頂點和texCoords / UVCoords中創建出THREE.Geometry，但這沒有用。

現在，我嘗試使用THREE.BufferGeometry（），但是我需要使用“ textures [0]”渲染索引0到287，使用“ textures [1]”渲染索引288到605，依此類推。

我的第一個嘗試是為每個零件創建一個索引為288到605的BufferGeometry，但是由於索引是針對孔模型的，因此我不得不將完整的頂點，法線和UVCoords放在Buffer中，僅用於幾個平面。

有沒有一種方法可以使用其他Texture渲染BufferGeometry的各個部分，或者為每個Face設置Texture Index？

還是可以創建一個材質，用材質A渲染前X個面，用材質B渲染下一個面？？？

Answer 1

如果要對單個BufferGeometry使用兩個不同的紋理，則可以使用此模式來設置drawcalls ：

var geometry1 = new THREE.BufferGeometry();
// ...and set the data...
var geometry2 = geometry1.clone();

// set drawcalls
geometry1.offsets = geometry1.drawcalls = []; // currently required
geometry1.addDrawCall( start1, count1, 0 );

geometry2.offsets = geometry2.drawcalls = []; // currently required
geometry2.addDrawCall( start2, count2, 0 );

var material1 = new THREE.MeshPhongMaterial( { map: map1 } );
var material2 = new THREE.MeshPhongMaterial( { map: map2 } );

var mesh1 = new THREE.Mesh( geometry1, material1 );
var mesh2 = new THREE.Mesh( geometry2, material2 );

three.js r.70

Answer 2

您可以創建兩個具有相同頂點緩沖區和不同索引的幾何：

var position = new THREE.BufferAttribute(positionArray, 3);
var normal = new THREE.BufferAttribute(normalArray, 3);
var uv = new THREE.BufferAttribute(uvArray, 2);

var indices1 = new THREE.BufferAttribute(indexArray1, 1);
var geometry1 = new THREE.BufferGeometry();
geometry1.addAttribute('position', position);
geometry1.addAttribute('normal', normal);
geometry1.addAttribute('uv', uv);
geometry1.addAttribute('index', indices1);

var indices2 = new THREE.BufferAttribute(indexArray2, 1);
var geometry2 = new THREE.BufferGeometry();
geometry2.addAttribute('position', position);
geometry2.addAttribute('normal', normal);
geometry2.addAttribute('uv', uv);
geometry2.addAttribute('index', indices2);

然后像平常一樣使用不同的材質創建2個網格。 據我了解，這將在兩個網格中重復使用相同的數據。