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Need help to complete a project

Started by November 04, 2000 12:49 PM
0 comments, last by Cosmond 24 years ago
Hi, I have to complete a project by next friday that has literaly just been thrown at me. I had no experience with Opengl, and quite basic ideas of C++. Anyway, I am now stuck. This is the source code that I have written so far: /* * course1.c/Mesa * 2d Graphics Game, Fire missile at the targets */ /* Note that your project type should be a "Win32 Console Application", and within Project -> Settings -> Link you should add "opengl32.lib glut32.lib glu32.lib" to the "Object/Library modules" text box. */ #include #include #define X_CENTRE 0.0 /* centre point of square */ #define Y_CENTRE 0.0 #define LENGTH 1.0 /* lengths of sides of square */ GLfloat angle = 0.0; /* angle of rotation in degrees (global) */ /* reshape callback function executed when window is moved or resized */ void reshape(int width, int height) { glViewport(0, 0, width, height); glMatrixMode(GL_PROJECTION); glLoadIdentity(); /* use orthographic (parallel) projection use xmin = 0, xmax = 1 ymin = 0, ymax = 1 znear = -1, zfar = 1 - not relevant here (2D) */ glOrtho(0.0, 1.0, 0.0, 1.0, 1.0, 0.0); glMatrixMode(GL_MODELVIEW); } /* display callback function called whenever contents of window need to be re-displayed */ void display(void) { glClear (GL_COLOR_BUFFER_BIT); /* clear window */ glColor3f(1.0, 1.0, 0.5); /* Yellow drawing objects */ /* Yellow Targets at top of screen*/ glBegin(GL_POLYGON); glVertex2f(0.125, 0.9); glVertex2f(0.125, 0.95); glVertex2f(0.2, 0.95); glVertex2f(0.2, 0.9); glEnd(); glBegin(GL_POLYGON); glVertex2f(0.4625, 0.9); glVertex2f(0.4625, 0.95); glVertex2f(0.5375, 0.95); glVertex2f(0.5375, 0.9); glEnd(); glBegin(GL_POLYGON); glVertex2f(0.8, 0.9); glVertex2f(0.8, 0.95); glVertex2f(0.875, 0.95); glVertex2f(0.875, 0.9 ); glEnd(); /* White Boundary Lines */ glColor3f(1.0, 1.0, 1.0); glBegin(GL_LINES); glVertex2f(0.0, 0.25); glVertex2f(0.12, 0.25); glVertex2f(1.0, 0.25); glVertex2f(0.88, 0.25); glEnd(); /* White Missile */ //glLoadIdentity(); glTranslatef( 0.5, 0.125, 0.0 ); // moves origin back to centre of missile glRotatef( angle, 0.0, 0.0, 1.0 ); // rotates about origin glTranslatef( -0.5, -0.125, 0.0 ); // moves centre point to origin // draw missile glColor3f(1.0, 1.0, 1.0); glBegin(GL_POLYGON); glVertex2f(0.5, 0.145); // top glVertex2f(0.49, 0.135); // top left corner glVertex2f(0.49, 0.105); // bottom left glVertex2f(0.51, 0.105); // bottom right glVertex2f(0.51, 0.135); // top right glEnd(); glLoadIdentity(); glFlush(); } /* graphics initialisation */ void init(void) { glClearColor (0.0, 0.0, 0.0, 0.0); /* window will be cleared to black */ } /* Keyboard callback function, called when keyboard used */ void keyboard(unsigned char key, int x, int y) { switch ( key ) { case ''r'': angle = angle - 5.0; glutPostRedisplay(); break; case ''l'': angle = angle + 5.0; glutPostRedisplay(); break; case ''e'': exit(0); break; default: break; } } void mouse (int button, int state, int x, int y) { switch (button) { case GLUT_LEFT_BUTTON: if (state == GLUT_DOWN) { GLint viewpoint[4]; GLdouble mvmatrix[16], projmatrix[16]; GLdouble wx, wy, wz; GLint realwy; GLdouble objx, objy, objz; glGetIntegerv (GL_VIEWPORT, viewpoint); glGetDoublev(GL_MODELVIEW_MATRIX, mvmatrix); glGetDoublev(GL_PROJECTION_MATRIX, projmatrix); realwy = viewpoint[3] - wy - 1; gluUnProject (wx, realwy, wz, mvmatrix, projmatrix, viewpoint, &objx, &objy, &objz); } break; //case GLUT_RIGHT_BUTTON: glutIdleFunc( idle ); case GLUT_RIGHT_BUTTON: exit(0); //for now exit, should be used to fire missile break; default: break; } } int main(int argc, char** argv) { /* window management code ... */ /* initialises GLUT and processes any command line arguments */ glutInit(&argc, argv); /* use single-buffered window and RGBA colour model */ glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB); /* window width = 400 pixels, height = 400 pixels */ glutInitWindowSize (400, 400); /* window upper left corner at (100, 100) */ glutInitWindowPosition (100, 100); /* creates an OpenGL window with command argument in its title bar */ glutCreateWindow (argv[0]); init(); glutDisplayFunc(display); glutReshapeFunc(reshape); /* register keyboard callback function */ glutKeyboardFunc(keyboard); /* register mouse callback function */ glutMouseFunc(mouse); glutMainLoop(); } It is a small game where the user controls a missile, they can rotate the missile and fire it. After many hours I can now rotate the missile, but I am totally stuck on the moving bit and hitting a target (needs to use double buffering as well). Firstly can anyone help me to move the missile when I right click on the mouse? (it should just move in the direction it is pointing), and when it hits a target the target should disappear, and the missile should return to its previous position at the bottom of the screen. Any help is welcome, I was required to use GLUT, it was not a personal choice. I am a beginner to C++ so this is not easy for me at all. Thanks Cos.
Try taking a look at NeHe''s site here at Gamedev.net. He can probably answer your question if all else fails...

"Any statements made by the above poster are strictly opion (unless otherwise stated) and may be offensible to some readers."

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