我克隆了以下示例：
https://github.com/JoeyDeVries/LearnOpenGL/tree/master/src/5.advanced_lighting/6.hdr
git clone https://github.com/JoeyDeVries/LearnOpenGL
cd LearnOpenGL
echo "static char const * logl_root = \".\";" > includes/learnopengl/root_directory.h
cp -avr resources src/5.advanced_lighting/6.hdr
cd src/5.advanced_lighting/6.hdr
g++ -std=c++11 hdr.cpp -lglut -lGL -lGLU -lGLEW -lm -lglfw3 -lpthread -lX11 -lXrandr -lXinerama -lXi -lXxf86vm -lXcursor -lGL -ldl -lSOIL -lassimp -I ../../../includes
编译好。但它在跑步方面存在问题。命令行窗口中的输出是
./a.out
Framebuffer not complete!
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
exposure: 1
输出是一个黑暗的窗口。
我该如何解决？
我不遵循安装指南，因为它们会导致其他一些错误，最后它们会停止。到目前为止，许多例子通过手工构建对我有用。但是这个HDR示例存在Framebuffer not complete!问题。
hdr.cpp
// GLEW
#define GLEW_STATIC
#include <GL/glew.h>
// GLFW
#include <GLFW/glfw3.h>
// GL includes
#include <learnopengl/shader.h>
#include <learnopengl/camera.h>
// GLM Mathemtics
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>
// Other Libs
#include <SOIL.h>
#include <learnopengl/filesystem.h>
// Properties
const GLuint SCR_WIDTH = 800, SCR_HEIGHT = 600;
// Function prototypes
void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode);
void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);
void mouse_callback(GLFWwindow* window, double xpos, double ypos);
void Do_Movement();
GLuint loadTexture(GLchar const * path);
void RenderScene(Shader &shader);
void RenderCube();
void RenderQuad();
// Camera
Camera camera(glm::vec3(0.0f, 0.0f, 5.0f));
// Delta
GLfloat deltaTime = 0.0f;
GLfloat lastFrame = 0.0f;
// Options
GLboolean hdr = true; // Change with 'Space'
GLfloat exposure = 1.0f; // Change with Q and E
// Global variables
GLuint woodTexture;
// The MAIN function, from here we start our application and run our Game loop
int main()
{
// Init GLFW
glfwInit();
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
glfwWindowHint(GLFW_RESIZABLE, GL_FALSE);
GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", nullptr, nullptr); // Windowed
glfwMakeContextCurrent(window);
// Set the required callback functions
glfwSetKeyCallback(window, key_callback);
glfwSetCursorPosCallback(window, mouse_callback);
glfwSetScrollCallback(window, scroll_callback);
// Options
glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
// Initialize GLEW to setup the OpenGL Function pointers
glewExperimental = GL_TRUE;
glewInit();
// Define the viewport dimensions
glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
// Setup some OpenGL options
glEnable(GL_DEPTH_TEST);
// Setup and compile our shaders
Shader shader("lighting.vs", "lighting.frag");
Shader hdrShader("hdr.vs", "hdr.frag");
// Light sources
// - Positions
std::vector<glm::vec3> lightPositions;
lightPositions.push_back(glm::vec3(0.0f, 0.0f, 49.5f)); // back light
lightPositions.push_back(glm::vec3(-1.4f, -1.9f, 9.0f));
lightPositions.push_back(glm::vec3(0.0f, -1.8f, 4.0f));
lightPositions.push_back(glm::vec3(0.8f, -1.7f, 6.0f));
// - Colors
std::vector<glm::vec3> lightColors;
lightColors.push_back(glm::vec3(200.0f, 200.0f, 200.0f));
lightColors.push_back(glm::vec3(0.1f, 0.0f, 0.0f));
lightColors.push_back(glm::vec3(0.0f, 0.0f, 0.2f));
lightColors.push_back(glm::vec3(0.0f, 0.1f, 0.0f));
// Load textures
woodTexture = loadTexture(FileSystem::getPath("resources/textures/wood.png").c_str());
// Set up floating point framebuffer to render scene to
GLuint hdrFBO;
glGenFramebuffers(1, &hdrFBO);
// - Create floating point color buffer
GLuint colorBuffer;
glGenTextures(1, &colorBuffer);
glBindTexture(GL_TEXTURE_2D, colorBuffer);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB16F, SCR_WIDTH, SCR_HEIGHT, 0, GL_RGB, GL_FLOAT, NULL);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// - Create depth buffer (renderbuffer)
GLuint rboDepth;
glGenRenderbuffers(1, &rboDepth);
glBindRenderbuffer(GL_RENDERBUFFER, rboDepth);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, SCR_WIDTH, SCR_HEIGHT);
// - Attach buffers
glBindFramebuffer(GL_FRAMEBUFFER, hdrFBO);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, colorBuffer, 0);
glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, rboDepth);
if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
std::cout << "Framebuffer not complete!" << std::endl;
glBindFramebuffer(GL_FRAMEBUFFER, 0);
glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
// Game loop
while (!glfwWindowShouldClose(window))
{
// Set frame time
GLfloat currentFrame = glfwGetTime();
deltaTime = currentFrame - lastFrame;
lastFrame = currentFrame;
// Check and call events
glfwPollEvents();
Do_Movement();
// 1. Render scene into floating point framebuffer
glBindFramebuffer(GL_FRAMEBUFFER, hdrFBO);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glm::mat4 projection = glm::perspective(camera.Zoom, (GLfloat)SCR_WIDTH / (GLfloat)SCR_HEIGHT, 0.1f, 100.0f);
glm::mat4 view = camera.GetViewMatrix();
glm::mat4 model;
shader.Use();
glUniformMatrix4fv(glGetUniformLocation(shader.Program, "projection"), 1, GL_FALSE, glm::value_ptr(projection));
glUniformMatrix4fv(glGetUniformLocation(shader.Program, "view"), 1, GL_FALSE, glm::value_ptr(view));
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, woodTexture);
// - set lighting uniforms
for (GLuint i = 0; i < lightPositions.size(); i++)
{
glUniform3fv(glGetUniformLocation(shader.Program, ("lights[" + std::to_string(i) + "].Position").c_str()), 1, &lightPositions[i][0]);
glUniform3fv(glGetUniformLocation(shader.Program, ("lights[" + std::to_string(i) + "].Color").c_str()), 1, &lightColors[i][0]);
}
glUniform3fv(glGetUniformLocation(shader.Program, "viewPos"), 1, &camera.Position[0]);
// - render tunnel
model = glm::mat4();
model = glm::translate(model, glm::vec3(0.0f, 0.0f, 25.0));
model = glm::scale(model, glm::vec3(5.0f, 5.0f, 55.0f));
glUniformMatrix4fv(glGetUniformLocation(shader.Program, "model"), 1, GL_FALSE, glm::value_ptr(model));
glUniform1i(glGetUniformLocation(shader.Program, "inverse_normals"), GL_TRUE);
RenderCube();
glBindFramebuffer(GL_FRAMEBUFFER, 0);
// 2. Now render floating point color buffer to 2D quad and tonemap HDR colors to default framebuffer's (clamped) color range
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
hdrShader.Use();
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, colorBuffer);
glUniform1i(glGetUniformLocation(hdrShader.Program, "hdr"), hdr);
glUniform1f(glGetUniformLocation(hdrShader.Program, "exposure"), exposure);
RenderQuad();
std::cout << "exposure: " << exposure << std::endl;
// Swap the buffers
glfwSwapBuffers(window);
}
glfwTerminate();
return 0;
}
// RenderQuad() Renders a 1x1 quad in NDC, best used for framebuffer color targets
// and post-processing effects.
GLuint quadVAO = 0;
GLuint quadVBO;
void RenderQuad()
{
if (quadVAO == 0)
{
GLfloat quadVertices[] = {
// Positions // Texture Coords
-1.0f, 1.0f, 0.0f, 0.0f, 1.0f,
-1.0f, -1.0f, 0.0f, 0.0f, 0.0f,
1.0f, 1.0f, 0.0f, 1.0f, 1.0f,
1.0f, -1.0f, 0.0f, 1.0f, 0.0f,
};
// Setup plane VAO
glGenVertexArrays(1, &quadVAO);
glGenBuffers(1, &quadVBO);
glBindVertexArray(quadVAO);
glBindBuffer(GL_ARRAY_BUFFER, quadVBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(quadVertices), &quadVertices, GL_STATIC_DRAW);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)0);
glEnableVertexAttribArray(1);
glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
}
glBindVertexArray(quadVAO);
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
glBindVertexArray(0);
}
// RenderCube() Renders a 1x1 3D cube in NDC.
GLuint cubeVAO = 0;
GLuint cubeVBO = 0;
void RenderCube()
{
// Initialize (if necessary)
if (cubeVAO == 0)
{
GLfloat vertices[] = {
// Back face
-0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f, // Bottom-left
0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f, // top-right
0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f, // bottom-right
0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f, // top-right
-0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f, // bottom-left
-0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 1.0f,// top-left
// Front face
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, // bottom-left
0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f, // bottom-right
0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f, // top-right
0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f, // top-right
-0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 1.0f, // top-left
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, // bottom-left
// Left face
-0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-right
-0.5f, 0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 1.0f, // top-left
-0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-left
-0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-left
-0.5f, -0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f, // bottom-right
-0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-right
// Right face
0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-left
0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-right
0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f, // top-right
0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-right
0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-left
0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, // bottom-left
// Bottom face
-0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f, // top-right
0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 1.0f, // top-left
0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f,// bottom-left
0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f, // bottom-left
-0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 0.0f, // bottom-right
-0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f, // top-right
// Top face
-0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f,// top-left
0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, // bottom-right
0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f, // top-right
0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, // bottom-right
-0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f,// top-left
-0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f // bottom-left
};
glGenVertexArrays(1, &cubeVAO);
glGenBuffers(1, &cubeVBO);
// Fill buffer
glBindBuffer(GL_ARRAY_BUFFER, cubeVBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
// Link vertex attributes
glBindVertexArray(cubeVAO);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)0);
glEnableVertexAttribArray(1);
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
glEnableVertexAttribArray(2);
glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(6 * sizeof(GLfloat)));
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindVertexArray(0);
}
// Render Cube
glBindVertexArray(cubeVAO);
glDrawArrays(GL_TRIANGLES, 0, 36);
glBindVertexArray(0);
}
// This function loads a texture from file. Note: texture loading functions like these are usually
// managed by a 'Resource Manager' that manages all resources (like textures, models, audio).
// For learning purposes we'll just define it as a utility function.
GLuint loadTexture(GLchar const * path)
{
// Generate texture ID and load texture data
GLuint textureID;
glGenTextures(1, &textureID);
int width, height;
unsigned char* image = SOIL_load_image(path, &width, &height, 0, SOIL_LOAD_RGB);
// Assign texture to ID
glBindTexture(GL_TEXTURE_2D, textureID);
glTexImage2D(GL_TEXTURE_2D, 0, GL_SRGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, image);
glGenerateMipmap(GL_TEXTURE_2D);
// Parameters
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glBindTexture(GL_TEXTURE_2D, 0);
SOIL_free_image_data(image);
return textureID;
}
bool keys[1024];
bool keysPressed[1024];
// Moves/alters the camera positions based on user input
void Do_Movement()
{
// Camera controls
if (keys[GLFW_KEY_W])
camera.ProcessKeyboard(FORWARD, deltaTime);
if (keys[GLFW_KEY_S])
camera.ProcessKeyboard(BACKWARD, deltaTime);
if (keys[GLFW_KEY_A])
camera.ProcessKeyboard(LEFT, deltaTime);
if (keys[GLFW_KEY_D])
camera.ProcessKeyboard(RIGHT, deltaTime);
if (keys[GLFW_KEY_SPACE] && !keysPressed[GLFW_KEY_SPACE])
{
hdr = !hdr;
keysPressed[GLFW_KEY_SPACE] = true;
}
// Change parallax height scale
if (keys[GLFW_KEY_Q])
exposure -= 0.5 * deltaTime;
else if (keys[GLFW_KEY_E])
exposure += 0.5 * deltaTime;
}
GLfloat lastX = 400, lastY = 300;
bool firstMouse = true;
// Is called whenever a key is pressed/released via GLFW
void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode)
{
if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
glfwSetWindowShouldClose(window, GL_TRUE);
if (key >= 0 && key <= 1024)
{
if (action == GLFW_PRESS)
keys[key] = true;
else if (action == GLFW_RELEASE)
{
keys[key] = false;
keysPressed[key] = false;
}
}
}
void mouse_callback(GLFWwindow* window, double xpos, double ypos)
{
if (firstMouse)
{
lastX = xpos;
lastY = ypos;
firstMouse = false;
}
GLfloat xoffset = xpos - lastX;
GLfloat yoffset = lastY - ypos;
lastX = xpos;
lastY = ypos;
camera.ProcessMouseMovement(xoffset, yoffset);
}
void scroll_callback(GLFWwindow* window, double xoffset, double yoffset)
{
camera.ProcessMouseScroll(yoffset);
}
答案 0 :(得分：1)
此处没有足够的信息来诊断问题，因此您需要进行一些调试。第一个嫌疑人将是您的OpenGL实现是否支持使用GL_RGB16F纹理作为帧缓冲附件。您可以尝试将其更改为GL_RGBA16F并查看是否有效。
除此之外，我建议在初始化期间添加一些额外的日志记录......
之前
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, colorBuffer, 0);
添加
std::cout << "Color buffer: " << colorBuffer << std::endl;
std::cout << "Depth buffer: " << rboDepth << std::endl;
这样您就可以在帧缓冲附件出现之前验证颜色缓冲区和深度缓冲区是否有效（非零）。另外，我会改变
if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
std::cout << "Framebuffer not complete!" << std::endl;
到
auto fboStatus = glCheckFramebufferStatus(GL_FRAMEBUFFER);
if (fboStatus != GL_FRAMEBUFFER_COMPLETE)
std::cout << "Framebuffer not complete: " << fboStatus << std::endl;
这样您就可以看到实际的帧缓冲状态，这可能会为您提供问题的线索。
当你学习在每次OpenGL调用之后调用glGetError（）以确保没有生成错误时，这也是一个好主意...
{
auto glstatus = glGetError();
if (glstatus != GL_NO_ERROR) { std::cout << "Error in GL call: << glstatus << std::endl; }
}