GLSL 3.30中未提供片段着色器输入布局位置限定符。您必须切换到GLSL 4.10或删除片段着色器中的布局位置：
我是OpenGL的新手，我想用我的着色器在屏幕上画一个简单的三角形。我设置了缓冲区并编写了着色器，但它似乎不起作用。它给出了白色屏幕，我试图用glGenBuffer更改glCreateBuffer，屏幕变成了黑色屏幕。我想创建&在一个名为createAndCompileShader(…(的函数中编译着色器，缓冲区在主函数中定义。
#include <GL/glew.h>
#include <GLFW/glfw3.h>
#include <string>
#include <iostream>
static unsigned int createAndCompileShader(const char* vertexShader, const char* fragmentShader) {
unsigned int fragmentShaderr = glCreateShader(GL_FRAGMENT_SHADER);
unsigned int vertexShaderr = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vertexShaderr, 1, &vertexShader, NULL);
glShaderSource(fragmentShaderr, 1, &fragmentShader, NULL);
glCompileShader(vertexShaderr);
glCompileShader(fragmentShaderr);
unsigned int program = glCreateProgram();
glAttachShader(program, vertexShaderr);
glAttachShader(program, fragmentShaderr);
glLinkProgram(program);
return program;
}
int main(void)
{
GLFWwindow* window;
/* Initialize the library */
if (!glfwInit())
return -1;
/* Create a windowed mode window and its OpenGL context */
window = glfwCreateWindow(640, 480, "Hello World", NULL, NULL);
if (!window)
{
glfwTerminate();
return -1;
}
/* Make the window's context current */
glfwMakeContextCurrent(window);
float vertexPositions[6] = {
-0.5, -0.5,
0.0, 0.5,
0.5, -0.5
};
const char* vertexShader = "#version 330 coren"
"layout(location = 0) in vec4 position;n"
"void main()n"
"{n"
"gl_Position = position;n"
"}n";
const char* fragementShader = "#version 330 coren"
"layout(location = 0) in vec4 position;n"
"void main()n"
"{n"
"color = vec4(1.0, 0.0, 0.0, 1.0);n"
"}n";
unsigned int program = createAndCompileShader(vertexShader, fragementShader);
glUseProgram(program);
unsigned int buffer;
glGenBuffers(1, &buffer);
//glCreateBuffers(1, &buffer);
glBindBuffer(GL_ARRAY_BUFFER, buffer);
glBufferData(GL_ARRAY_BUFFER, 6 * sizeof(float), vertexPositions, GL_STATIC_DRAW);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, sizeof(float)*2 , 0);
//std::string vertexShader;
//std::string fragmentShader;
/* Loop until the user closes the window */
while (!glfwWindowShouldClose(window))
{
/* Render here */
glClear(GL_COLOR_BUFFER_BIT);
glDrawArrays(GL_TRIANGLES, 0 ,3);
/*glBegin(GL_TRIANGLES);
glVertex2f(-0.5, -0.5);
glVertex2f( 0.0, 0.5);
glVertex2f( 0.5, -0.5);
glEnd();*/
/* Swap front and back buffers */
glfwSwapBuffers(window);
/* Poll for and process events */
glfwPollEvents();
}
glDeleteProgram(program);
glfwTerminate();
return 0;
}
layout(location = 0) in vec4 position;
in vec4 position;
此外，您还错过了片段着色器输出color的规范。
#version 330 core
in vec4 position;
out vec4 color;
void main()
{
color = vec4(1.0, 0.0, 0.0, 1.0);
}
我建议使用原始字符串升数：
const char* fragementShader = R"(#version 330 core
in vec4 position;
out vec4 color;
void main()
{
color = vec4(1.0, 0.0, 0.0, 1.0);
})";
检查着色器编译是否成功以及程序对象是否成功链接
如果着色器编译成功，可以通过glGetShaderiv和参数GL_COMPILE_STATUS进行检查
如果程序链接成功，可以通过glGetProgramiv和参数GL_LINK_STATUS进行检查
(请参阅此问题的答案。(
如果使用核心配置文件OpenGL上下文，则默认的顶点阵列对象无效。创建一个命名的VAO:
unsigned int VAO;
glCreateVertexArrays(1, &VAO);
glBindVertexArray(VAO);
unsigned int buffer;
glGenBuffers(1, &buffer);
glBindBuffer(GL_ARRAY_BUFFER, buffer);
glBufferData(GL_ARRAY_BUFFER, 6 * sizeof(float), vertexPositions, GL_STATIC_DRAW);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, sizeof(float)*2 , 0);
GLEW必须由glewInit()初始化。请参阅初始化GLEW:
glfwMakeContextCurrent(window);
glewInit();