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我在尝试将网格导入我的程序以使用粒子/弹簧系统进行布料模拟物理时遇到了一些问题。我是图形编程的初学者，很抱歉，如果这非常明显并且我只是遗漏了一些东西。我使用 C++ 和 OpenGL，以及 Assimp 来导入模型。我相当确定我计算约束/弹簧和步进每个粒子的代码是正确的，因为我使用生成的网格（使用四边形而不是三角形）对其进行了测试，它看起来不错，但是 idk。

我一直在使用此链接来研究如何实际执行此操作：https ://nccastaff.bournemouth.ac.uk/jmacey/MastersProjects/MSc2010/07LuisPereira/Thesis/LuisPereira_Thesis.pdf

引擎内的样子：https ://www.youtube.com/watch?v=RyAan27wryU

我很确定这是连接/弹簧的问题，因为在大多数情况下，只是平面的进口模型似乎可以正常工作。另一个模型虽然..似乎只是分崩离析。我一直在看这方面的论文，据我所知，一切都应该正常工作，因为我似乎正确地连接了边缘/弯曲弹簧，并且物理方面似乎是从平面上工作的。我这辈子真的想不通！任何提示/帮助将不胜感激！:)

将Mesh加工成Cloth的代码：

// Container to temporarily hold faces while we process springs
std::vector<Face> faces;

// Go through indices and take the ones making a triangle.
// Indices come from assimp, so i think this is the right thing to do to get each face?
for (int i = 0; i < this->indices.size(); i+=3)
{
        std::vector<unsigned int> faceIds = { this->indices.at(i), this->indices.at(i + 1), this->indices.at(i + 2) };
        Face face;
        face.vertexIDs = faceIds;
        faces.push_back(face);
}

// Iterate through faces and add constraints when needed.
for (int l = 0; l < faces.size(); l++)
{

    // Adding edge springs.
    Face temp = faces[l];
    makeConstraint(particles.at(temp.vertexIDs[0]), particles.at(temp.vertexIDs[1]));
    makeConstraint(particles.at(temp.vertexIDs[0]), particles.at(temp.vertexIDs[2]));
    makeConstraint(particles.at(temp.vertexIDs[1]), particles.at(temp.vertexIDs[2]));


    // We need to get the bending springs as well, and i've just written a function to do that.
    for (int x = 0; x < faces.size(); x++)
    {
        Face temp2 = faces[x];
        if (l != x)
        {
            verticesShared(temp, temp2);
        }

    }
}

这是我处理弯曲弹簧的代码：

// Container for any indices the two faces have in common. 
std::vector<glm::vec2> traversed;

// Loop through both face's indices, to see if they match eachother. 
for (int i = 0; i < a.vertexIDs.size(); i++)
{
    for (int k = 0; k < b.vertexIDs.size(); k++)
    {

        // If we do get a match, we push a vector into the container containing the two indices of the faces so we know which ones are equal.
        if (a.vertexIDs.at(i) == b.vertexIDs.at(k))
        {
            traversed.push_back(glm::vec2(i, k));
        }
    }
    // If we're here, if means we have an edge in common, aka that we have two vertices shared between the two faces.
    if (traversed.size() == 2)
    {
        // Get the adjacent vertices.
         int face_a_adj_ind = 3 - ((traversed[0].x) + (traversed[1].x));
         int face_b_adj_ind = 3 - ((traversed[0].y) + (traversed[1].y));

        // Turn the stored ones from earlier and just get the ACTUAL indices from the face. Indices of indices, eh. 
        unsigned int adj_1 = a.vertexIDs[face_a_adj_ind];
        unsigned int adj_2 = b.vertexIDs[face_b_adj_ind];
        // And finally, make a bending spring between the two adjacent particles. 
        makeConstraint(particles.at(adj_1), particles.at(adj_2));
    }
}
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