所以我想使用 VAO 和 VBO 绘制一个形状,我认为我做的一切都是正确的,但每当我运行我的代码时,我只会得到带有清晰颜色的窗口。当我在调用创建功能之前尝试初始化三角形时,我遇到了一个问题,我是否缺少一些开始绘图的函数?
这是我的代码:
int vaoId, vboId, vertexCount;
float[] vertices = {
// Left bottom triangle
-0.5f, 0.5f,
-0.5f, -0.5f,
0.5f, -0.5f,};
private void init() {
if (!glfwInit()) {
throw new IllegalStateException("Failed to Initialize GLFW!");
}
int width = 1000;
int height = 1000;
glfwWindowHint(GLFW_VISIBLE, GLFW_FALSE);
window = glfwCreateWindow(width, height, "App", NULL, NULL);
if (window == 0) {
throw new IllegalStateException("Failed to create Window!");
}
GLFWVidMode videoMode = glfwGetVideoMode(glfwGetPrimaryMonitor());
glfwSetWindowPos(window, (videoMode.width() - width) / 2, (videoMode.height() - height) / 2);
// Make the OpenGL context current
glfwMakeContextCurrent(window);
// Enable v-sync
glfwSwapInterval(1);
glfwShowWindow(window);
}
private void loop() {
// This line is critical for LWJGL's interoperation with GLFW's
// OpenGL context, or any context that is managed externally.
// LWJGL detects the context that is current in the current thread,
// creates the GLCapabilities instance and makes the OpenGL
// bindings available for use.
GL.createCapabilities();
initTriangle();
// Run the rendering loop until the user has attempted to close
// the window or has pressed the ESCAPE key.
while (!glfwWindowShouldClose(window)) {
glClear(GL_COLOR_BUFFER_BIT); // clear the framebuffer
glBindVertexArray(vaoId);
glEnableVertexAttribArray(0);
glDrawArrays(GL_TRIANGLES, 0, vertexCount);
glDisableVertexAttribArray(0);
glBindVertexArray(0);
glfwSwapBuffers(window); // swap the color buffers
// Poll for window events. The key callback above will only be
// invoked during this call.
glfwPollEvents();
}
}
private void initTriangle() {
FloatBuffer vertBuf = MemoryUtil.memAllocFloat(vertices.length);
vertBuf.put(vertices);
vertBuf.flip();
vaoId = glGenVertexArrays();
glBindVertexArray(vaoId);
vboId = glGenBuffers();
glBindBuffer(GL_ARRAY_BUFFER, vboId);
glBufferData(GL_ARRAY_BUFFER, vertBuf, GL_STATIC_DRAW);
glVertexAttribPointer(0, 2, GL_FLOAT, false, 0, 0);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindVertexArray(0);
}
希望大家帮忙,非常感谢。
最佳答案
I am not using shaders. Is that my problem? And is it a necessity
OpenGL 中最先进的渲染方式是使用 Shader 。
如果您不使用着色器,则必须通过 glVertexPointer
定义顶点数据数组
vaoId = glGenVertexArrays();
glBindVertexArray(vaoId);
vboId = glGenBuffers();
glBindBuffer(GL_ARRAY_BUFFER, vboId);
glBufferData(GL_ARRAY_BUFFER, vertBuf, GL_STATIC_DRAW);
glVertexPointer( 2, GL_FLOAT, 0, 0 ); // <---------------
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindVertexArray(0);
并且您必须通过 glEnableClientState( GL_VERTEX_ARRAY )
启用顶点坐标的客户端功能:
glBindVertexArray(vaoId);
glEnableClientState( GL_VERTEX_ARRAY ); // <---------------
glDrawArrays(GL_TRIANGLES, 0, vertexCount);
glDisableClientState( GL_VERTEX_ARRAY ); // <---------------
glBindVertexArray(0);
<小时/>
注意,客户端能力(或顶点属性数组)的此状态存储在 Vertex Array Object 中。 因此,当指定顶点数组对象时,启用顶点坐标就足够了。绘制几何体时,可以省略顶点坐标的启用和禁用:
vaoId = glGenVertexArrays();
glBindVertexArray(vaoId);
vboId = glGenBuffers();
glBindBuffer(GL_ARRAY_BUFFER, vboId);
glBufferData(GL_ARRAY_BUFFER, vertBuf, GL_STATIC_DRAW);
glVertexPointer( 2, GL_FLOAT, 0, 0 );
glEnableClientState( GL_VERTEX_ARRAY ); // <---------------
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindVertexArray(0);
glBindVertexArray(vaoId);
glDrawArrays(GL_TRIANGLES, 0, vertexCount);
glBindVertexArray(0);
关于java - 尝试使用 LWJGL3 绘制基本形状,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/51390730/