opengl 相关问题

OpenGL（开放图形库）是一种独立于平台的图形标准和API，可用于桌面，工作站和移动设备。它旨在提供硬件加速渲染，因此与传统软件渲染相比，性能大大提高。 OpenGL用于CAD软件和计算机游戏等应用程序。 OpenGL标准以及OpenGL ES由Khronos集团控制。

在 OpenGL 顶点着色器中，w 是什么，为什么要除以它？

无效主（无效） { vec4 ClipCoord = glModelViewProjectionmatrix * gl_Vertex; gl_Position = 剪辑坐标； gl_FrontColor = gl_Color; vec3 ndc = 剪辑坐标.xyz / 剪辑坐标.w; 所以clipCoord是...

opengl vertex-shader

回答 1 投票 0

X 请求失败错误：GLXBadFBConfig

我正在尝试按照“交互式计算机图形”中的规定制作谢尔宾斯基垫片基于着色器的 OPENGL® 的自顶向下方法”第 6 版。我有这个代码谢尔宾斯基.cpp #包括我正在尝试按照“交互式计算机图形”中的指定制作谢尔宾斯基垫片基于着色器的 OPENGL® 的自上而下方法” 第 6 版。我有这个代码谢尔宾斯基.cpp #include <GL/glew.h> #include <GL/glut.h> #include <glm/glm.hpp> #include "Angel.h" #include <iostream> #include <vector> #include <cmath> #define NUM_PUNTOS 4 #define DIVISIONES 5 namespace Global { GLint Ndivisions = DIVISIONES; GLint Nvertices = (GLint) std::pow(3,Ndivisions + 1); std::vector<glm::vec2> points; }; void display(void); void init(); //void idle(void); void triangle(glm::vec2,glm::vec2,glm::vec2,std::vector<glm::vec2> &); void divide_triangle(glm::vec2,glm::vec2,glm::vec2,GLint,std::vector<glm::vec2> &); inline glm::vec2 dividir(glm::vec2,double); glm::vec2 dividir(glm::vec2,double); int main(int argc, char **argv) { glutInit(&argc,argv); glutInitDisplayMode(GLUT_RGBA); glutInitWindowSize(800,600); glutInitContextVersion(3,2); glutInitContextProfile(GLUT_CORE_PROFILE); //IMPORTANTE: CREAR ANTES QUE LOS CALLBACKS glutCreateWindow("Sierpinski gasket"); //Init glewInit();//IMPORTANTÍSIMO init(); glutDisplayFunc(display); #ifdef LIBGL_DEBUG std::cout<<LIBGL_DEBUG<<'\n'; #endif //Despues de todo es que se crea la ventana glutMainLoop(); } void display(void) { glClear(GL_COLOR_BUFFER_BIT); glDrawArrays(GL_POINTS, 0, Global::Nvertices); glFlush(); } void init() { //Inicializamos array global divide_triangle(glm::vec2(0.0,0.0),glm::vec2(1.0,0.0),glm::vec2(0.5,1.0),Global::Ndivisions,Global::points); glm::vec2 *points = &Global::points[0]; GLuint vao,program; program = Angel::InitShader("shaders/Sierpinski.vertex.glsl", "shaders/Sierpinski.fragment.glsl"); glUseProgram(program); for(int x = 0; x<Global::points.size();x++) std::cout<<"X: "<<points[x].x<<" Y: "<<points[x].y<<"\n"; glGenVertexArrays(1, &vao); glBindVertexArray(vao); //Buffers GLuint buffer; glGenBuffers(1, &buffer); std::cout<<"Primer test\n"; glBindBuffer(GL_ARRAY_BUFFER, buffer); glBufferData(GL_ARRAY_BUFFER,sizeof(points), points,GL_STATIC_DRAW); //glGenVertexArrays(1, &buffer); //glBindVertexArray(buffer); std::cout<<buffer<<'\n'; // Initialize the vertex position attribute from the vertex shader GLuint loc = glGetAttribLocation( program, "vPosition" ); glEnableVertexAttribArray( loc ); glVertexAttribPointer( loc, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0) ); } void triangle(glm::vec2 a,glm::vec2 b,glm::vec2 c,std::vector<glm::vec2> &points) { size_t old_size = points.size(); points.resize(old_size + 3); points[old_size] = a; points[old_size + 1] = b; points[old_size + 2] = c; //std::cout<<"Finalizado\n"; } void divide_triangle(glm::vec2 a,glm::vec2 b,glm::vec2 c,GLint k,std::vector<glm::vec2> &points) { if(k>0) { glm::vec2 ab = dividir(a + b,2.0); glm::vec2 ac = dividir(a + c,2.0); glm::vec2 bc = dividir(b + c,2.0); //Dividimos triángulo int new_k = k - 1; divide_triangle(a,ab,ac,new_k,points); divide_triangle(c,ac,bc,new_k,points); divide_triangle(b,bc,ab,new_k,points); } else { triangle(a,b,c,points); } } glm::vec2 dividir(glm::vec2 vectorcito,double escalar) { return glm::vec2(vectorcito.x/escalar,vectorcito.y/escalar); } //void idle(void){} 天使.h ////////////////////////////////////////////////////////////////////////////// // // --- Angel.h --- // // The main header file for all examples from Angel 6th Edition // ////////////////////////////////////////////////////////////////////////////// #ifndef __ANGEL_H__ #define __ANGEL_H__ //---------------------------------------------------------------------------- // // --- Include system headers --- // #include <cmath> #include <iostream> // Define M_PI in the case it's not defined in the math header file #ifndef M_PI # define M_PI 3.14159265358979323846 #endif //---------------------------------------------------------------------------- // // --- Include OpenGL header files and helpers --- // // The location of these files vary by operating system. We've included // copies of open-soruce project headers in the "GL" directory local // this this "include" directory. // #ifdef __APPLE__ // include Mac OS X verions of headers # include <OpenGL/OpenGL.h> # include <GLUT/glut.h> #else // non-Mac OS X operating systems # include <GL/glew.h> # include <GL/freeglut.h> # include <GL/freeglut_ext.h> #endif // __APPLE__ // Define a helpful macro for handling offsets into buffer objects #define BUFFER_OFFSET( offset ) ((GLvoid*) (offset)) //---------------------------------------------------------------------------- // // --- Include our class libraries and constants --- // namespace Angel { // Helper function to load vertex and fragment shader files GLuint InitShader( const char* vertexShaderFile, const char* fragmentShaderFile ); // Defined constant for when numbers are too small to be used in the // denominator of a division operation. This is only used if the // DEBUG macro is defined. const GLfloat DivideByZeroTolerance = GLfloat(1.0e-07); // Degrees-to-radians constant const GLfloat DegreesToRadians = M_PI / 180.0; } // namespace Angel /*#include "vec.h" #include "mat.h" #include "CheckError.h"*/ #define Print(x) do { std::cerr << #x " = " << (x) << std::endl; } while(0) // Globally use our namespace in our example programs. //using namespace Angel; namespace Angel { // Create a NULL-terminated string by reading the provided file static char* readShaderSource(const char* shaderFile) { FILE* fp = fopen(shaderFile, "r"); if ( fp == NULL ) { return NULL; } fseek(fp, 0L, SEEK_END); long size = ftell(fp); fseek(fp, 0L, SEEK_SET); char* buf = new char[size + 1]; fread(buf, 1, size, fp); buf[size] = '\0'; fclose(fp); return buf; } // Create a GLSL program object from vertex and fragment shader files GLuint InitShader(const char* vShaderFile, const char* fShaderFile) { struct Shader { const char* filename; GLenum type; GLchar* source; } shaders[2] = { { vShaderFile, GL_VERTEX_SHADER, NULL }, { fShaderFile, GL_FRAGMENT_SHADER, NULL } }; GLuint program = glCreateProgram(); for ( int i = 0; i < 2; ++i ) { Shader& s = shaders[i]; s.source = readShaderSource( s.filename ); if ( shaders[i].source == NULL ) { std::cerr << "Failed to read " << s.filename << std::endl; exit( EXIT_FAILURE ); } GLuint shader = glCreateShader( s.type ); glShaderSource( shader, 1, (const GLchar**) &s.source, NULL ); glCompileShader( shader ); GLint compiled; glGetShaderiv( shader, GL_COMPILE_STATUS, &compiled ); if ( !compiled ) { std::cerr << s.filename << " failed to compile:" << std::endl; GLint logSize; glGetShaderiv( shader, GL_INFO_LOG_LENGTH, &logSize ); char* logMsg = new char[logSize]; glGetShaderInfoLog( shader, logSize, NULL, logMsg ); std::cerr << logMsg << std::endl; delete [] logMsg; exit( EXIT_FAILURE ); } delete [] s.source; glAttachShader( program, shader ); } /* link and error check */ glLinkProgram(program); GLint linked; glGetProgramiv( program, GL_LINK_STATUS, &linked ); if ( !linked ) { std::cerr << "Shader program failed to link" << std::endl; GLint logSize; glGetProgramiv( program, GL_INFO_LOG_LENGTH, &logSize); char* logMsg = new char[logSize]; glGetProgramInfoLog( program, logSize, NULL, logMsg ); std::cerr << logMsg << std::endl; delete [] logMsg; exit( EXIT_FAILURE ); } /* use program object */ glUseProgram(program); return program; } } // Close namespace Angel block #endif // __ANGEL_H__ 我使用以下命令编译它 g++ Sierpinski.cpp -I. -lGL -lglut -lGLU -lGLEW -g -o Sierpinski.out 当我运行它时，出现以下内容： [asdrubal@localhost tests]$ ./Sierpinski.out libGL error: failed to load driver: i965 libGL error: Try again with LIBGL_DEBUG=verbose for more details. libGL error: failed to load driver: swrast libGL error: Try again with LIBGL_DEBUG=verbose for more details. X Error of failed request: GLXBadFBConfig Major opcode of failed request: 154 (GLX) Minor opcode of failed request: 34 () Serial number of failed request: 39 Current serial number in output stream: 38 有什么建议吗？ P.S.：我现在正在使用 3.6.9-1-ARCH (Arch Linux) 编辑1：着色器谢尔宾斯基.fragment.glsl void main() { gl_FragColor = vec4(0.0,1.0,0.0,1.0); } Sierpinski.vertex.glsl #version 120 attribute vec4 vPosition; /*Si se quieren setear variables*/ void main() { gl_Position = vPosition; } LIBGL_DEBUG=verbose 的输出 [asdrubal@localhost tests]$ ./Sierpinski.out libGL: OpenDriver: trying /usr/lib32/dri/tls/i965_dri.so libGL: OpenDriver: trying /usr/lib32/dri/i965_dri.so libGL error: dlopen /usr/lib32/dri/i965_dri.so failed (/usr/lib32/dri/i965_dri.so: cannot open shared object file: No such file or directory) libGL error: unable to load driver: i965_dri.so libGL error: driver pointer missing libGL error: failed to load driver: i965 libGL: OpenDriver: trying /usr/lib32/dri/tls/swrast_dri.so libGL: OpenDriver: trying /usr/lib32/dri/swrast_dri.so libGL error: dlopen /usr/lib32/dri/swrast_dri.so failed (/usr/lib32/dri/swrast_dri.so: cannot open shared object file: No such file or directory) libGL error: unable to load driver: swrast_dri.so libGL error: failed to load driver: swrast X Error of failed request: GLXBadFBConfig Major opcode of failed request: 154 (GLX) Minor opcode of failed request: 34 () Serial number of failed request: 39 Current serial number in output stream: 38 编辑2：命令： lspci | grep VGA 退货 00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (primary) (rev 03) Intel Corporation Mobile GM965/GL960 您正在运行第四代英特尔芯片，因此： glutInitContextVersion(3,2); 相当...乐观. 除非您想要软件渲染，在这种情况下，您将需要等待一段时间Mesa才能升级到OpenGL 3.2。编辑：尝试一下： #include <GL/glew.h> #include <GL/glut.h> #include <glm/glm.hpp> #include <iostream> #include <vector> #include <cmath> #include <stdexcept> using namespace std; // vertex shader const GLchar* vert = "#version 120\n" "attribute vec2 position;" "void main()" "{" " gl_Position = vec4( position, 0.0, 1.0 );" "}" ; // fragment shader const GLchar* frag = "#version 120\n" "void main()" "{" " gl_FragColor = vec4( 0.0, 1.0, 0.0, 1.0 );" "}" ; const unsigned int NUM_PUNTOS = 4; const unsigned int DIVISIONES = 5; namespace Global { GLint Ndivisions = DIVISIONES; GLint Nvertices = (GLint) std::pow(3.0,Ndivisions + 1); std::vector<glm::vec2> points; }; void triangle( glm::vec2 a, glm::vec2 b, glm::vec2 c, std::vector<glm::vec2> &points ) { size_t old_size = points.size(); points.resize(old_size + 3); points[old_size] = a; points[old_size + 1] = b; points[old_size + 2] = c; } glm::vec2 dividir( glm::vec2 vectorcito, double escalar ) { return glm::vec2(vectorcito.x/escalar,vectorcito.y/escalar); } void divide_triangle( glm::vec2 a, glm::vec2 b, glm::vec2 c, GLint k, std::vector<glm::vec2> &points ) { if(k>0) { glm::vec2 ab = dividir(a + b,2.0); glm::vec2 ac = dividir(a + c,2.0); glm::vec2 bc = dividir(b + c,2.0); //Dividimos triángulo int new_k = k - 1; divide_triangle(a,ab,ac,new_k,points); divide_triangle(c,ac,bc,new_k,points); divide_triangle(b,bc,ab,new_k,points); } else { triangle(a,b,c,points); } } void CheckStatus( const GLenum id ) { GLint status = GL_FALSE, loglen = 10; if( glIsShader(id) ) glGetShaderiv( id, GL_COMPILE_STATUS, &status ); if( glIsProgram(id) ) glGetProgramiv( id, GL_LINK_STATUS, &status ); if( GL_TRUE == status ) return; if( glIsShader(id) ) glGetShaderiv( id, GL_INFO_LOG_LENGTH , &loglen); if( glIsProgram(id) ) glGetProgramiv( id, GL_INFO_LOG_LENGTH , &loglen); vector< char > log( loglen, 'E' ); if( glIsShader(id) ) glGetShaderInfoLog( id, loglen, NULL, &log[0] ); if( glIsProgram(id) ) glGetProgramInfoLog( id, loglen, NULL, &log[0] ); throw logic_error( string( log.begin(), log.end() ) ); } GLuint CreateShader( const GLenum aType, const string& aSource ) { GLuint shader = glCreateShader( aType ); const GLchar* shaderString = aSource.c_str(); glShaderSource( shader, 1, &shaderString, NULL ); glCompileShader( shader ); CheckStatus( shader ); return shader; } GLuint CreateProgram( const string& aVertexShader, const string& aFragmentShader ) { GLuint vert = CreateShader( GL_VERTEX_SHADER, aVertexShader ); GLuint frag = CreateShader( GL_FRAGMENT_SHADER, aFragmentShader ); GLuint program = glCreateProgram(); glAttachShader( program, vert ); glAttachShader( program, frag ); glLinkProgram( program ); glDeleteShader( vert ); glDeleteShader( frag ); CheckStatus( program ); return program; } GLuint prog = 0; GLuint vbo = 0; void init() { GLenum glewError = glewInit(); if( GLEW_OK != glewError ) throw runtime_error( (char*)glewGetErrorString(glewError) ); cout << "GL_VERSION : " << glGetString(GL_VERSION) << endl; cout << "GL_VENDOR : " << glGetString(GL_VENDOR) << endl; cout << "GL_RENDERER : " << glGetString(GL_RENDERER) << endl; cout << "GLEW_VERSION : " << glewGetString(GLEW_VERSION) << endl; cout << "GLSL VERSION : " << glGetString(GL_SHADING_LANGUAGE_VERSION) << endl; if( !GLEW_VERSION_2_1 ) throw runtime_error( "OpenGL 2.1 or better required for GLSL support." ); // load shaders prog = CreateProgram( vert, frag ); //Inicializamos array global divide_triangle ( glm::vec2(0.0,0.0), glm::vec2(1.0,0.0), glm::vec2(0.5,1.0), Global::Ndivisions, Global::points ); // create/fill VBO glGenBuffers( 1, &vbo ); glBindBuffer( GL_ARRAY_BUFFER, vbo ); unsigned int numBytes = sizeof( glm::vec2 ) * Global::points.size(); glBufferData( GL_ARRAY_BUFFER, numBytes, &Global::points[0].x, GL_STATIC_DRAW ); } void display(void) { glClear( GL_COLOR_BUFFER_BIT ); glUseProgram( prog ); GLint position_loc = glGetAttribLocation( prog, "position" ); glBindBuffer( GL_ARRAY_BUFFER, vbo ); glVertexAttribPointer( position_loc, 2, GL_FLOAT, GL_FALSE, sizeof( glm::vec2 ), 0 ); glEnableVertexAttribArray( position_loc ); glDrawArrays( GL_POINTS, 0, Global::points.size() ); glDisableVertexAttribArray( position_loc ); glutSwapBuffers(); } int main(int argc, char **argv) { glutInit( &argc, argv ); glutInitWindowSize( 800,600 ); glutInitDisplayMode( GLUT_RGBA | GLUT_DOUBLE ); glutCreateWindow( "Sierpinski gasket" ); init(); glutDisplayFunc( display ); glutMainLoop(); return 0; }

c++ opengl glut

回答 1 投票 0

在我的光线行进着色器中，当物体经过原点光源附近时，为什么阴影会反转？

我正在使用有符号距离函数 (SDF) 在 OpenGL 着色器中实现光线行进阴影。光源放置在原点 (0,0,0)，我使用光线行进来计算 sh...

opengl glsl shadow fragment-shader raymarching

回答 1 投票 0

为什么glfw窗口老是消失？

代码编译正常，但是当我执行 a.out 时，窗口出现一瞬间然后再次消失。我怎样才能让它留在那里？我正在 bodhi linux 5.15.0-78-generic 上编译与 g++ -lG...

c++ opengl glfw

回答 1 投票 0

在 GLSL (OpenGL) 中计算向量交集

我想为场景添加雾。但我不想根据片段与相机的距离向片段颜色添加雾，而是想采用更现实的方法。我想计算距离，...