c++生成球的顶点和面索引CreateSphere

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我想找个代码在D3D11中创建一个球体，结果发现很多代码都不合适。它们往往只生成顶点，不生成面索引，比如：

http://gamedev.stackexchange.com/questions/16585/how-do-you-programmatically-generate-a-sphere

所以，自己写了一个。

#include "DXUT.h"#include "wrMesh.h"#include "wrMath.h"struct wrSimpleVertexInput{    DirectX::XMFLOAT3 position;    DirectX::XMFLOAT3 normal;};using namespace DirectX;void CreateSphere(float r, int stacks, int slices, wrSimpleVertexInput** vArr, DWORD** iArr){    const float PI = WR_M_PI;    wrSimpleVertexInput*& pV = *vArr;    DWORD*& pI = *iArr;    int nv = (stacks - 1)*slices + 2;    int nf = (stacks-1)*slices * 2;    const int offsetv1 = 1;    const int offsetv2 = nv - slices - 1;    const int offseti1 = 3 * slices;    const int offseti2 = 3 * (nf - slices);    pV = new wrSimpleVertexInput[nv];    pV[0].position = XMFLOAT3(0.f, r, 0.f);    pV[nv - 1].position = XMFLOAT3(0.f, -r, 0.f);    for (int t = 1; t < stacks; t++) // stacks are ELEVATION so they count theta    {        float theta = ((float)(t) / stacks)*PI;        for (int p = 0; p < slices; p++) // slices are ORANGE SLICES so the count azimuth        {            float phi = ((float)(p) / slices) * 2 * PI; // azimuth goes around 0 .. 2*PI            auto &v = pV[slices * (t-1) + p + offsetv1];            vec3 pos, norm;            pos[0] = sinf(theta) * cosf(phi);            pos[1] = cosf(theta);            pos[2] = sinf(theta) * sinf(phi);            vec3_copy(reinterpret_cast<float*>(&v.position), pos);            vec3_norm(norm, pos);            vec3_copy(reinterpret_cast<float*>(&v.normal), norm);        }    }    pI = new DWORD[3*nf];    for (int t = 0; t < slices; t++)    {        pI[3 * t] = 0;        pI[3 * t + 1] = t + offsetv1;        pI[3 * t + 2] = (t + 1) % slices + offsetv1;        pI[3 * t + offseti2] = nv - 1;        pI[3 * t + 1 + offseti2] = (t + 1) % slices + offsetv2;        pI[3 * t + 2 + offseti2] = t + offsetv2;    }    for (int t = 0; t < stacks - 2; t++) // stacks are ELEVATION so they count theta    {        auto ptr = pI + t * slices * 6 + offseti1;        for (int p = 0; p < slices; p++) // slices are ORANGE SLICES so the count azimuth        {            //phi1   phi2            // |      |            // 1------2 -- theta1            // |\ _   |            // |    \ |            // 4------3 -- theta2            //            int v1 = offsetv1 + slices * t + p;            int v2 = offsetv1 + slices * t + p + 1;            int v3 = offsetv1 + slices * (t + 1) + p + 1;            int v4 = offsetv1 + slices * (t + 1) + p;                        ptr[0] = v1;    ptr[1] = v3;    ptr[2] = v2;            ptr[3] = v1;    ptr[4] = v4;    ptr[5] = v3;            ptr += 6;        }    }}

望指正。

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