正确使用 glVertexAttribPointer？

Question

我最近决定开始学习 OpenGL，并给自己买了一本关于 OpenGL Core 3.3 的书。书一般都是讲C++的

所以，经过一番寻找，我找到了一个我更擅长的语言的库，它提供了几乎相同的功能：lwjgl.

我按照书中的步骤将 C++ 语法翻译成 java 语法，直到它开始实际绘制一些东西。

不管我对代码做了什么更改，JVM 一直崩溃。经过一些调试后，我发现当我调用 glVertexAttribPointer 或 glDrawArrays.

时 JVM 崩溃了

我是 OpenGL 的新手，我假设这个问题对于更有经验的人来说一定听起来很愚蠢，但是：关于这段代码我需要更改什么？

        

        float[] vertices = {
                -0.5f, -0.5f, -0.0f,    
                0.5f, 0.5f, 0.0f,
                0.0f,0.5f,0.0f
        };
        FloatBuffer b = BufferUtils.createFloatBuffer(9);
        b.put(vertices);
        int VBO = glGenBuffers();
        int VAO = glGenVertexArrays();
        log.info("VBO:" + VBO + "VAO: " + VAO);
        // bind the Vertex Array Object first, then bind and set vertex buffer(s), and then configure vertex attributes(s).
        glBindVertexArray(VAO);

            
        glVertexAttribPointer(0, 3, GL_FLOAT, false, 12,  0);
        glEnableVertexAttribArray(0);
        glBindBuffer(GL_ARRAY_BUFFER, VBO);
        glBufferData(GL_ARRAY_BUFFER, vertices, GL_STATIC_DRAW);
        glBindVertexArray(0);       

            

        // Run the rendering loop until the user has attempted to close
        // the window or has pressed the ESCAPE key.
        while (!glfwWindowShouldClose(window))
            {
                // input
                // -----

                // render
                // ------
                glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
                glClear(GL_COLOR_BUFFER_BIT);

                // draw our first triangle
                glUseProgram(shaderProgram);
                glBindVertexArray(VAO); // seeing as we only have a single VAO there's no need to bind it every time, but we'll do so to keep things a bit more organized
                glDrawArrays(GL_TRIANGLES, 0, 3);
                 glBindVertexArray(0); // no need to unbind it every time 
         
                // glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
                // -------------------------------------------------------------------------------
                glfwSwapBuffers(window);
                glfwPollEvents();
            }

我将非常感谢我能得到的任何帮助，如果您需要更多信息/需要查看更多我的代码，请告诉我。提前致谢

Answer 1

在指定顶点属性之前，您必须将顶点缓冲区对象绑定到目标 GL_ARRAY_BUFFER：

glBindBuffer(GL_ARRAY_BUFFER, VBO); 
glVertexAttribPointer(0, 3, GL_FLOAT, false, 12,  0);

当glVertexAttribPointer is called, the buffer object currently bound to the ARRAY_BUFFER target is associated to the attribute (index) and a reference to the buffer object is stored in the state vector of the Vertex Array Object.

正确使用 glVertexAttribPointer？

Correct Use of glVertexAttribPointer?

java

opengl

lwjgl

vao