glut

问题 Both GLUT and libdispatch have their own event-handling loops, which are invoked with functions that never return: glutMainLoop(); and dispatch_main(); , respectively. I've tried: dispatch_queue_t q = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0); dispatch_async(q, ^{ glutMainLoop(); }); dispatch_main(); ...and the window displays, but does not respond to any events or redraw after the initial call to the function specified with glutDisplayFunc() . How can I get GLUT and

问题 I am new to openGL and wanted to set the text color tried the glColor3f function but it changes the drawing color as i only want to change the text color what should i do? 回答1: You could push the current colour onto the attribute stack, change the colour, draw the text, and then pop the stack to restore the original colour: glPushAttrib(GL_CURRENT_BIT); glColor3f(...); // Draw your text glPopAttrib(); // This sets the colour back to its original value 回答2: glColor3f is the correct call, but

问题 I am new to OpenGL and I am still experimenting with basic shapes. I sometimes find many functions like glEnd and many more, that are not mentioned in the OpenGL 3+ documentation. Were they replaced by other functions? Or do I have to write them manually? Is there a tutorial online that uses OpenGL 3+? As for " gluPerspective" I have read that it isn't used in Opengl 3+. Isn't it supposed to be a separate function in GLUT? what does it has to do with OpenGL 3+? Last, what does Transform(

问题 I would like to know how to open multiple OpenGL/Glut windows. And I mean multiple windows at the same time not subwindows and not update the same window 回答1: The same way as you would create one window, except you should do it multiple times : #include <cstdlib> #include <GL/glut.h> // Display callback ------------------------------------------------------------ float clr = 0.2; void display() { // clear the draw buffer . glClear(GL_COLOR_BUFFER_BIT); // Erase everything // set the color to

问题 I use Glut to make a simple animation. In the main function, glutTimerFunc(TIMERMSECS, animate, 0) is called. The two pieces of codes generate the same graphic. const int TIMERMSECS = 20; float animation_time = 0; const float animation_step = .5; Method 1: void animate(int t){ float time_elapsed = TIMERMSECS/1000.0; float current_step = animation_step* time_elapsed; glutTimerFunc(TIMERMSECS, animate, 0); if(current_step < animation_step*2) animation_time += current_step; glutPostRedisplay();

问题 I'm using Ubuntu and tried using synaptic to install everything that had the word "GLUT" in it and also SDL and opengl . But still a simple program fails to compile . It shows this : opengl1.cpp:(.text+0xe): undefined reference to `glClear' opengl1.cpp:(.text+0x1a): undefined reference to `glBegin' opengl1.cpp:(.text+0x2e): undefined reference to `glVertex2i' opengl1.cpp:(.text+0x33): undefined reference to `glEnd' opengl1.cpp:(.text+0x38): undefined reference to `glFlush' /tmp/ccnwQeLu.o: In

问题 Having asked this before I tried out a lot of things and found out that the problem has to do with glutInit. Take the following code examples: main.cpp #include <iostream> #include <memory> #include<GL/glut.h> using namespace std; int main(int argcp, char **argv) { shared_ptr<double> abc; glutInit(&argcp,argv); cout<<"Hello!"<<endl; return 0; } compiled with: g++ -std=c++11 -g -Wall -o appx main.cpp -lGL -lGLU -lglut cause the executable to instantly crash (no "Hello!" output) with segfault

问题 By (5, 5) I mean exactly the fifth row and fifth column. I found it very hard to draw things using screen coordinates, all the coordinates in OpenGL is relative, and usually ranging from -1.0 to 1.0. Why it is so serious to prevent programmers from using screen coordinates / window coordinates? 回答1: I did a bit of 3D programming several years back and, while I'm far from an expert, I think you are overlooking a very important difference between classical bitmapped DrawPixel(x, y) graphics and

问题 Think of your basic GLUT programs. They simply run from a main method and contain callbacks like `glutMouseFunc(MouseButton) where MouseButton is the name of a method. What I have done is I have encapsulated the main file into a class, so that MouseButton is no longer a static function but has an instance. But doing this gives me a compilation error : Error 2 error C3867: 'StartHand::MouseButton': function call missing argument list; use '&StartHand::MouseButton' to create a pointer to member

问题 Think of your basic GLUT programs. They simply run from a main method and contain callbacks like `glutMouseFunc(MouseButton) where MouseButton is the name of a method. What I have done is I have encapsulated the main file into a class, so that MouseButton is no longer a static function but has an instance. But doing this gives me a compilation error : Error 2 error C3867: 'StartHand::MouseButton': function call missing argument list; use '&StartHand::MouseButton' to create a pointer to member