立方体在OpenGL中的位置

Question

此代码的输出是25个旋转的小熊。我面临的问题是每个多维数据集的位置，我不知道如何将它们放在一行中，例如，一行中每5个多维数据集等等。

注意：我已经添加了多维数据集的位置。

glm::vec3 cubePositions[] = {
    glm::vec3(0.0f,  0.0f,  0.0f),
    glm::vec3(2.0f,  5.0f, -15.0f),
    glm::vec3(-1.5f, -2.2f, -2.5f),
    glm::vec3(-3.8f, -2.0f, -12.3f),
    glm::vec3(2.4f, -0.4f, -3.5f),
    glm::vec3(-1.7f,  3.0f, -7.5f),
    glm::vec3(1.3f, -2.0f, -2.5f),
    glm::vec3(1.5f,  2.0f, -2.5f),
    glm::vec3(1.5f,  0.2f, -1.5f),
    glm::vec3(-1.3f,  1.0f, -1.5f)
};

while (!glfwWindowShouldClose(mainWindow))
{
    glfwPollEvents();

    glClearColor(0.0f, 0.1f, 0.2f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    //Camera transformation
    glm::mat4 projection = glm::mat4(1.0f);
    glm::mat4 view = glm::mat4(1.0f);
    projection = glm::perspective(glm::radians(45.0f), (float)WIDTH / (float)HEIGHT, 0.1f, 100.0f);
    view = glm::translate(view, glm::vec3(0.0f, 0.0f, -3.0f));

    //Get uniform locations
    GLint viewlLoc = glGetUniformLocation(ourShader.Program, "view");
    glUniformMatrix4fv(viewlLoc, 1, GL_FALSE, glm::value_ptr(view));
    GLint projlLoc = glGetUniformLocation(ourShader.Program, "projection");
    glUniformMatrix4fv(projlLoc, 1, GL_FALSE, glm::value_ptr(projection));

    // Call Shader Program
    ourShader.Use();

    glBindVertexArray(VAO);

    for(unsigned int i = 0; i < 25; i++)
    {
        glm::mat4 model = glm::mat4(1.0f);
        model = glm::translate(model, cubePositions[i]);
        float angle = 20.0f * i;
        angle = glfwGetTime() * 25.0f;
        model = glm::rotate(model, glm::radians(angle), glm::vec3(1.0f, 0.3f, 0.5f));
        GLint modelLoc = glGetUniformLocation(ourShader.Program, "model");
        glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));

        glDrawArrays(GL_TRIANGLES, 0, 36);
    }

    glBindVertexArray(0);

    glfwSwapBuffers(mainWindow);
    glfwPollEvents();
}

Answer 1

使用glm::translate将转换添加到每个单独的多维数据集的模型矩阵中，具体取决于多维数据集的索引。例如：

glm::translate

注意，您必须定义立方体之间的距离（

for(unsigned int i = 0; i < 25; i++)
{
    float dist = ; // distance between the cubes
    float x = (i % 5) * dist;
    float y = (i / 5) * dist;

    float angle = 20.0f * i;
    angle = glfwGetTime() * 25.0f;

    glm::mat4 model = glm::mat4(1.0f);
    model = glm::translate(model, glm::vector3(x, y, 0.0f));
    model = glm::rotate(model, glm::radians(angle), glm::vec3(1.0f, 0.3f, 0.5f));

    GLint modelLoc = glGetUniformLocation(ourShader.Program, "model");
    glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));

    glDrawArrays(GL_TRIANGLES, 0, 36);
}

）。

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注意，矩阵的级联（乘法dist）不是*。如果要旋转整个立方体块，则必须在旋转之前进行平移：

Commutative

由于分别为Commutative和model = rotate * translate ，定义一个矩阵并将输入矩阵乘以新矩阵，因此glm::rotate必须在glm::rotate之前完成：

glm::translate

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您可以使用算法来计算glm::translate：

glm::rotate

glm::translate