由于某些原因，当我运行程序时颜色不会呈现。随着glm的加入，我遇到了一些运行时出现的奇怪图像问题。它可能是一个图书馆，但它非常值得怀疑。我检查并重新检查了我的包含和库。我正在使用Eclipse。
这是我的代码
/*
* Module5.cpp
*
* Created on: Aug 21, 2017
* Author:
*/
#include <iostream>
#include <Gl/glew.h>
#include <GL/freeglut.h>
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>
using namespace std;
#define WINDOW_TITLE "Window"
#ifndef GLSL
#define GLSL(Version, Source) "#version " #Version "\n" #Source
#endif
GLint shaderProgram, WindowWidth = 800, WindowHeight = 600;
GLuint VBO, VAO; //Global variables for Buffer Object etc.
GLfloat cameraSpeed = 0.0005f;
GLchar currentKey; //will store key pressed
glm::vec3 cameraPosition = glm::vec3(0.0f, 0.0f, 5.0f);
glm::vec3 CameraUpY = glm::vec3(0.0f, 1.0f, 0.0f);
glm::vec3 CameraForwardZ = glm::vec3(0.0f, 0.0f, -1.0f);
void UResizeWindow(int, int);
void URenderGraphics(void);
void UCreateShader(void);
void UCreateBuffers(void);
void UKeyboard(unsigned char key, int x, int y);
void UKeyReleased(unsigned char key, int x, int y);
const GLchar * vertexShaderSource = GLSL(330,
layout(location=0) in vec3 position; //incoming data
layout(location=1) in vec3 color;
out vec4 mobileColor; //Attrib pointer 0
//out vec4 colorFromVShader;
//uniform mat4 primitiveTransform; //transform for shape
uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;
void main()
{
//gl_Position = primitiveTransform * vertex_Position; //move object on y-axis .5
gl_Position = projection * view * model * vec4(position, 1.0f); //move object on y-axis .5
//colorFromVShader = colorFromVBO;
mobileColor = color;
}
);
const GLchar * fragmentShaderSource = GLSL(440,
in vec3 mobileColor;
out vec4 gpuColor;
void main(){
// gl_FragColor= vec4(1.0, 0.5, 0.0, 1.0);
gpuColor= vec4(mobileColor, 1.0);
}
);
//Main
int main(int argc, char* argv[])
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA);
glutInitWindowSize(WindowWidth, WindowHeight);
glutCreateWindow(WINDOW_TITLE);
glutReshapeFunc(UResizeWindow);
glewExperimental = GL_TRUE;
if(glewInit() != GLEW_OK)
{
cout << "Failed to initialize glew!" << endl;
return -1;
}
UCreateShader();
UCreateBuffers();
glUseProgram(shaderProgram);
glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
glutDisplayFunc(URenderGraphics);
glutKeyboardFunc(UKeyboard);
glutKeyboardUpFunc(UKeyReleased);
glutMainLoop();
glDeleteVertexArrays(1, &VAO);//cleanup
glDeleteBuffers(1, &VBO);//cleanup
return 0;
}
void UResizeWindow(int w, int h)
{
WindowWidth = w;
WindowHeight = h;
glViewport(0, 0, WindowWidth, WindowHeight);
}
void URenderGraphics(void)
{
glEnable(GL_DEPTH_TEST);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);//clears screen
glBindVertexArray(VAO); //activate vertex array to render the vertices that render our shape
if(currentKey == 'w')
cameraPosition += cameraSpeed * CameraForwardZ;
if(currentKey == 's')
cameraPosition -= cameraSpeed * CameraForwardZ;
if(currentKey == 'a')
cameraPosition -= cameraSpeed * CameraForwardZ;
if(currentKey == 'd')
cameraPosition += cameraSpeed * CameraForwardZ;
glm::mat4 model;
model = glm::translate(model,glm::vec3(0.0f, 0.0f, 0.0));
model = glm::rotate(model, glm::radians(-45.0f), glm::vec3(0.0f, 1.0f, 0.0f)); //rotate shape x-axis by 1.0f
model = glm::scale(model, glm::vec3(2.0f, 2.0f, 2.0f)); //scale shape
glm::mat4 view; //camera
view = glm::lookAt(cameraPosition, cameraPosition + CameraForwardZ, CameraUpY); //move camera back by 5 (z)
glm::mat4 projection;
projection = glm::perspective(45.0f, (GLfloat)WindowWidth / (GLfloat)WindowHeight, 0.1f, 100.0f);
//projection = glm::ortho(-5.0f, 5.0f, -5.0f, 5.0f, 0.1f, 100.0f);
GLint modelLoc = glGetUniformLocation(shaderProgram, "model");
GLint viewLoc = glGetUniformLocation(shaderProgram, "view");
GLint projLoc = glGetUniformLocation(shaderProgram, "projection");
glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));
glUniformMatrix4fv(viewLoc, 1, GL_FALSE, glm::value_ptr(view));
glUniformMatrix4fv(projLoc, 1, GL_FALSE, glm::value_ptr(projection));
//apply projection matrix
/*
glm::mat4 newTransform; //references 4 x 4 matrix
newTransform = glm::translate(newTransform, glm::vec3(0.0f, 0.5f, 0.0)); //make square move up y-axis
newTransform = glm::rotate(newTransform, glm::radians(45.0f), glm::vec3(0.0f, 0.0f, 1.0f)); //rotate shape
//newTransform = glm::scale(newTransform, glm::vec3(0.5f, 0.5f, 0.5f)); //rotate shape
GLuint transformInfo = glGetUniformLocation(ProgramId, "primitiveTransform"); //id for shader, name of variable shader
glUniformMatrix4fv(transformInfo, 1, GL_FALSE, glm::value_ptr(newTransform));
*/
glutPostRedisplay();
glDrawArrays(GL_TRIANGLES, 0 , 36);
glBindVertexArray(0);
glutSwapBuffers();
}
void UCreateShader()
{
GLuint vertexShader = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vertexShader, 1, &vertexShaderSource, NULL);
glCompileShader(vertexShader);
GLuint fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(fragmentShader, 1, &fragmentShaderSource, NULL);
glCompileShader(fragmentShader);
shaderProgram = glCreateProgram();
glAttachShader(shaderProgram, vertexShader);
glAttachShader(shaderProgram, fragmentShader);
glLinkProgram(shaderProgram);
glDeleteShader(vertexShader);
glDeleteShader(fragmentShader);
}
/*void applyDepthSettings() {
glClearColor(0.0f, 0.0f, 0.0f, 1.0f); // Set background color to black and opaque
glClearDepth(1.0f);
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LEQUAL);
glShadeModel(GL_SMOOTH);
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
}*/
void UCreateBuffers()
{
//specify coords for creating square
// Positon and Color data
GLfloat vertices[] = {
// Vertex Positions // Colors
-0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, // Top Right Vertex 0
0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, // Bottom Right Vertex 1
0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, // Bottom Left Vertex 2
0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f, // Top Left Vertex 3
-0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f,
-0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f,
-0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 0.0f, // Top Right Vertex 0
0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 0.0f, // Bottom Right Vertex 1
0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, // Bottom Left Vertex 2
0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, // Top Left Vertex 3
-0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f,
-0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 0.0f,
-0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, // Top Right Vertex 0
-0.5f, 0.5f, -0.5f, 0.0f, 0.0f, 1.0f, // Bottom Right Vertex 1
-0.5f, -0.5f, -0.5f, 0.0f, 0.0f, 1.0f, // Bottom Left Vertex 2
-0.5f, -0.5f, -0.5f, 0.0f, 0.0f, 1.0f, // Top Left Vertex 3
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f,
-0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f,
0.5f, 0.5f, 0.5f, 1.0f, 1.0f, 0.0f, // Top Right Vertex 0
0.5f, 0.5f, -0.5f, 1.0f, 1.0f, 0.0f, // Bottom Right Vertex 1
0.5f, -0.5f, -0.5f, 1.0f, 1.0f, 0.0f, // Bottom Left Vertex 2
0.5f, -0.5f, -0.5f, 1.0f, 1.0f, 0.0f, // Top Left Vertex 3
0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 0.0f,
0.5f, 0.5f, 0.5f, 1.0f, 1.0f, 0.0f,
-0.5f, -0.5f, -0.5f, 0.0f, 1.0f, 1.0f, // Top Right Vertex 0
0.5f, -0.5f, -0.5f, 0.0f, 1.0f, 1.0f, // Bottom Right Vertex 1
0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 1.0f, // Bottom Left Vertex 2
0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 1.0f, // Top Left Vertex 3
-0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 1.0f,
-0.5f, -0.5f, -0.5f, 0.0f, 1.0f, 1.0f,
-0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 1.0f, // Top Right Vertex 0
0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 1.0f, // Bottom Right Vertex 1
0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 1.0f, // Bottom Left Vertex 2
0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 1.0f, // Top Left Vertex 3
-0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 1.0f,
-0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 1.0f,
};
//generate id's for buffer object
glGenVertexArrays(1, &VAO); //generate for Vertex Array Object
glGenBuffers(1, &VBO); //generate for Vertex Buffer Object
glBindVertexArray(VAO); //activate text array object
glBindBuffer(GL_ARRAY_BUFFER, VBO); //activating VBO buffer
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW); //pass in size of array from line 128
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(GLfloat), (GLvoid*)0);//send data to shader (accepts 6 arguments)GL_FALSE=not using normalization
glEnableVertexAttribArray(0);//enable vertex attribute pointer, starting position of x,y,z
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));//send data to shader (accepts 6 arguments)GL_FALSE=not using normalization
glEnableVertexAttribArray(1);//specify color starting point
glBindVertexArray(0); //deactivate vertex array object (VBO)
}
void UKeyboard(unsigned char key, GLint x, GLint y)
{
switch(key)
{
case'w':
cout<<"You pressed W!" <<endl;
break;
case 's':
cout<<"You pressed S!"<<endl;
break;
case'a':
cout<<"You pressed A!"<<endl;
break;
case 'd':
cout<<"You pressed D!"<<endl;
break;
default:
cout<<"Press a key!"<<endl;
}
}
/*Implements the UKeyReleased function*/
void UKeyReleased(unsigned char key, GLint x, GLint y)
{
cout<<"Key released"<<endl;
}
答案 0 :(得分：3)
您的顶点着色器无法编译，因为mobileColor的类型为vec4而color的类型为vec3。
变化：
mobileColor = color;
为：
mobileColor = vec4(color, 1.0);
注意，您的着色器程序未使用，因为它未成功构建。您绘制的所有内容都是默认使用当前设置的Theory绘制的OpenGL绘制的，默认情况下为 white （1,1,1,1）。
glColor是否可以检查着色器的编译是否成功，并且可以使用glGetShaderiv检索错误消息：
GLint status = GL_TRUE;
glCompileShader( shaderStage );
glGetShaderiv( shaderStage, GL_COMPILE_STATUS, &status );
if ( status == GL_FALSE )
{
GLint logLen;
glGetShaderiv( shaderStage, GL_INFO_LOG_LENGTH, &logLen );
std::vector< char >log( logLen+1 );
GLsizei written;
glGetShaderInfoLog( shaderStage, logLen, &written, log.data() );
std::cout << "compile error:" << std::endl << log.data() << std::endl;
}
glGetShaderInfoLog可以检查程序是否已成功链接，并且可以使用glGetProgramiv检索错误消息：
GLint status = GL_TRUE;
glLinkProgram( shaderProgram );
glGetProgramiv( shaderProgram, GL_LINK_STATUS, &status );
if ( status == GL_FALSE )
{
GLint logLen;
glGetProgramiv( shaderProgram, GL_INFO_LOG_LENGTH, &logLen );
std::vector< char >log( logLen+1 );
GLsizei written;
glGetProgramInfoLog( shaderProgram, logLen, &written, log.data() );
std::cout << "link error:" << std::endl << log.data() << std::endl;
}