I have to make a simple 3d game.
The game scenario consists of a spacecraft that is attacking the home planet
by firing rockets from along its length randomly. The game player moves the
baton up and down to stop the rockets before they reach the planet.
The star field behind the main scene should drift slowly from bottom to top
with new stars appearing from the bottom as the old stars disappear from the
top.
I have manage to draw the planet and the stars but, but need help with the stars to move from bottom to top, and need help to draw a spaceship firing rockets the spaceship.Rockets and the spacecraft can be built of either triangular faces or
quadrics or a mix of both.
here's my code plz help me to draw the spaceship firing rockets as i have no idea how to draw it.
#include "shared/gltools.h" // OpenGL toolkit
#include "shared/MathsUtils.h" // Mathematical toolkit
#include <string.h>
#define X_CENTRE 0.00 // centre point of co-ordinate system //
#define Y_CENTRE 0.00
#define Z_CENTRE 0.00
#define WIDTH 100 //X-max
#define HEIGHT -100
float STEP = 00.0; //Float used for Shield Y-axis translation amount
Point*points; //Array used to create "star" points. X Column and Y row
float starTranslation = -100.00;
void *font = GLUT_BITMAP_TIMES_ROMAN_24;
void output(int x, int y, char *string)
{
int len,i;
glRasterPos2f(x,y);
len = (int) strlen(string);
for(i= 0; i<len; i++){
glutBitmapCharacter(font, string[i]);
}
}
void keyboard(unsigned char key, int x, int y)
{
switch (key)
{
case 'p': //P-key is pressed
STEP = STEP + 5.0;//Shield moves up the X-axis by 5.0
glutPostRedisplay();
break;
case 'l': //L-key is pressed
STEP = STEP - 5.0;//Shield moves down the X-axis by 5.0
glutPostRedisplay();
break;
default: break;//Any other key, do nothing
}
}
void createRandomStarArray(int numOfStars,float xMin,float xMax, float yMin,float yMax, float zMin, float zMax)
{
//Create a random array of points
//first seed the random generator
srand((unsigned)time(0));
//instantiate an array of points
points = new Point[numOfStars];
//xScope and yScope are the full absolute width of the screen
int xScope = (int)(abs(xMin) + (abs(xMax)));
int yScope = (int)(abs(yMin) + (abs(yMax)));
int zScope = (int)(abs(zMin) + (abs(zMax)));
for(int index=0; index<numOfStars; index++){
points[index].x = rand()%(xScope)+1.0 - abs(xMin);
points[index].y = rand()%(yScope)+1.0 - abs(yMin);
points[index].z = rand()%(zScope)+1.0 - abs(zMin);
glPointSize(3);
glEnable(GL_POINT_SMOOTH);
glBegin(GL_POINTS);
glColor3ub(200, 200, 200); //white colour for the stars
glVertex3f(points[index].x, points[index].y, points[index].z);
glEnd();
glFlush();
}
}
void reshape(int width, int height)
{
glViewport(0, 0, width, height);
glMatrixMode (GL_PROJECTION);
glLoadIdentity ();
/* use orthographic (parallel) projection
use xmin = -100, xmax = 100
ymin = -100, ymax = 100*/
glOrtho(-100, WIDTH, HEIGHT, 100, -100, 100);
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
}
void drawPlanet() // to draw planet
{ //
//
glColor3ub(5, 5, 60); // Blue Planet Earth
glutSolidSphere(50, 100, 16); //25 for Radius and 50 for Sides
}
void display(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);// Clear the window with current clearing color
glMatrixMode(GL_MODELVIEW); // Save the matrix state and do the rotations
//Function to create stars amount set to 50, parameters set to othographic projection
createRandomStarArray(60,-100,100,-100,100,100,100);
//Move Co-ordinates
glPopMatrix();
glPushMatrix();
glTranslatef(0.0f, 10.0f, 0.0f);//Original Co-ordinates (0,10)
// draw planet
glPushMatrix();
glTranslatef(0.0, -110, -50.0);//Translate co-ordinantes to the far right, and draw planet
drawPlanet();
glPopMatrix();//Reset to Orginal co-ordinates
glutSwapBuffers();
}
/* graphics initialisation */
void init(void)
{
glClearColor (0.0, 0.0, 0.0, 0.0); //window set to colour black
}
int main(int argc, char** argv) // blackboard codes..
{
glutInit(&argc, argv); //initialises GLUT and processes any command line arguments
glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);//use double-buffered window and RGBA colour model and depth
glutInitWindowSize(800, 700); //window width and height 800 pixels and width 700
glutInitWindowPosition (0, 0); //window upper left corner at (0, 0) */
glutCreateWindow ("coursework");
glutDisplayFunc(display);
glutReshapeFunc(reshape);
glutKeyboardFunc(keyboard);
glutMainLoop();
return 0;
}
