LWJGL - 一个系统上的 VBO 渲染，而不是另一个系统

Question

我最近决定重新审视我根据 LWJGL wiki 上的教程使用 Indexed VBO 编写的一些 LWJGL 渲染代码。在我的台式计算机上，一切都按预期工作，但是当我切换到学校笔记本电脑时，它拒绝渲染任何内容。

我有以下渲染代码：

GL20.glUseProgram（pId）; System.out.println（"NO Error？ " + （GL11.glGetError（） == GL11.GL_NO_ERROR））;

    // Bind to the VAO that has all the information about the vertices and colors
    GL30.glBindVertexArray(vaoId);
    GL20.glEnableVertexAttribArray(0);
    GL20.glEnableVertexAttribArray(1);
    System.out.println("NO Error? " + (GL11.glGetError() == GL11.GL_NO_ERROR));
    // Bind to the index VBO that has all the information about the order of the vertices
    GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, vboiId);
    // Draw the vertices
    GL11.glDrawElements(GL11.GL_TRIANGLES, indicesCount, GL11.GL_UNSIGNED_INT, 0);
    System.out.println("NO Error? " + (GL11.glGetError() == GL11.GL_NO_ERROR));
    // Put everything back to default (deselect)
    GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, 0);
    GL20.glDisableVertexAttribArray(0);
    GL20.glDisableVertexAttribArray(1);
    GL30.glBindVertexArray(0);
    GL20.glUseProgram(0);
    System.out.println("NO Error? " + (GL11.glGetError() == GL11.GL_NO_ERROR));

这是我的顶点/片段着色器

#version 130
uniform mat4 MVP;
in vec4 in_Position;
in vec4 in_Color;
out vec4 pass_Color;
void main(void) {
gl_Position = MVP * in_Position;
pass_Color = in_Color;
}
#version 130
in vec4 pass_Color;
out vec4 out_Color;
void main(void) {
out_Color = pass_Color;
}

这是我的 VBO 初始化函数

public void initialize(float[] vertices, float[] colors, int[] indices) {
    shaderSetup();
    //create the buffers to hold vertex color and index data
    FloatBuffer verticesBuffer = BufferUtils.createFloatBuffer(vertices.length);
    verticesBuffer.put(vertices);
    verticesBuffer.flip();
    System.out.println("NO Error? " + (GL11.glGetError() == GL11.GL_NO_ERROR));
    FloatBuffer colorsBuffer = BufferUtils.createFloatBuffer(colors.length);
    colorsBuffer.put(colors);
    colorsBuffer.flip();
    // OpenGL expects vertices in counter clockwise order by default
    indicesCount = indices.length;
    IntBuffer indicesBuffer = BufferUtils.createIntBuffer(indicesCount);
    indicesBuffer.put(indices);
    indicesBuffer.flip();
    System.out.println("NO Error? " + (GL11.glGetError() == GL11.GL_NO_ERROR));
    // Create a new Vertex Array Object in memory and select it (bind)
    vaoId = GL30.glGenVertexArrays();
    GL30.glBindVertexArray(vaoId);
    System.out.println("NO Error? " + (GL11.glGetError() == GL11.GL_NO_ERROR));
    // Create a new Vertex Buffer Object in memory and select it (bind) - VERTICES
    vboId = GL15.glGenBuffers();
    GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, vboId);
    GL15.glBufferData(GL15.GL_ARRAY_BUFFER, verticesBuffer, GL15.GL_STATIC_DRAW);
    GL20.glVertexAttribPointer(0, 4, GL11.GL_FLOAT, false, 0, 0);
    GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
    System.out.println("NO Error? " + (GL11.glGetError() == GL11.GL_NO_ERROR));
    // Create a new Vertex Buffer Object in memory and select it (bind) - COLORS
    vbocId = GL15.glGenBuffers();
    GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, vbocId);
    GL15.glBufferData(GL15.GL_ARRAY_BUFFER, colorsBuffer, GL15.GL_STATIC_DRAW);
    GL20.glVertexAttribPointer(1, 4, GL11.GL_FLOAT, false, 0, 0);
    GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
    System.out.println("NO Error? " + (GL11.glGetError() == GL11.GL_NO_ERROR));
    // Deselect (bind to 0) the VAO
    GL30.glBindVertexArray(0);
    // Create a new VBO for the indices and select it (bind) - INDICES
    System.out.println("NO Error? " + (GL11.glGetError() == GL11.GL_NO_ERROR));
    vboiId = GL15.glGenBuffers();
    GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, vboiId);
    GL15.glBufferData(GL15.GL_ELEMENT_ARRAY_BUFFER, indicesBuffer, GL15.GL_STATIC_DRAW);
    GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, 0);
    System.out.println("NO Error? " + (GL11.glGetError() == GL11.GL_NO_ERROR));
}

着色器设置代码：

int errorCheckValue = GL11.glGetError();
// Load the vertex shader
vsId = this.loadShader("Shaders/vertex.glsl", GL20.GL_VERTEX_SHADER);
// Load the fragment shader
fsId = this.loadShader("Shaders/fragment.glsl", GL20.GL_FRAGMENT_SHADER);
// Create a new shader program that links both shaders
pId = GL20.glCreateProgram();
GL20.glAttachShader(pId, vsId);
GL20.glAttachShader(pId, fsId);
GL20.glLinkProgram(pId);
// Position information will be attribute 0
GL20.glBindAttribLocation(pId, 0, "in_Position");
// Color information will be attribute 1
GL20.glBindAttribLocation(pId, 1, "in_Color");
GL20.glValidateProgram(pId);
errorCheckValue = GL11.glGetError();
if (errorCheckValue != GL11.GL_NO_ERROR) {
System.out.println("ERROR - Could not create the shaders");
    System.exit(-1);
}

我家里的台式机（按预期渲染所有内容）运行的是 nVidia GTX 460 显卡，我的学校笔记本电脑（不渲染任何东西）有 AMD Firepro m4000 显卡。我最好的猜测是 VBO 渲染/创建/着色器代码的某些部分与我的 m4000 卡不兼容，但我找不到 glGetError（） 的任何错误。

Answer 1

着色

器设置代码中的调用顺序将无法按预期工作：

GL20.glLinkProgram(pId);
GL20.glBindAttribLocation(pId, 0, "in_Position");
GL20.glBindAttribLocation(pId, 1, "in_Color");

glBindAttribLocation()需要先调用才能glLinkProgram()生效。从手册页：

属性绑定在调用 glLinkProgram 之前不会生效。成功链接程序对象后，泛型属性的索引值将保持固定（并且可以查询其值），直到下一个链接命令发生。

因此，调用的顺序需要为：

GL20.glBindAttribLocation(pId, 0, "in_Position");
GL20.glBindAttribLocation(pId, 1, "in_Color");
GL20.glLinkProgram(pId);

虽然不是正确性问题，但您也没有非常有效地使用 VAO。属性启用/禁用值和GL_ELEMENT_ARRAY_BUFFER绑定是 VAO 状态的一部分。因此，您可以在设置过程中调用glEnableVertexAttribArray()并GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, vboiId)一次，同时绑定 VAO。然后在绘制调用中，您只需要绑定 VAO 即可设置所有状态。