package com.peterhi.ui.gl;
import javax.media.opengl.GL;
import javax.media.opengl.GL2;
import javax.media.opengl.glu.GLU;
public class OneTriangle {
protected static void setup( GL2 gl2, int width, int height ) {
gl2.glMatrixMode( GL2.GL_PROJECTION );
gl2.glLoadIdentity();
// coordinate system origin at lower left with width and height same as the window
GLU glu = new GLU();
glu.gluOrtho2D( 0.0f, width, 0.0f, height );
gl2.glMatrixMode( GL2.GL_MODELVIEW );
gl2.glLoadIdentity();
gl2.glViewport( 0, 0, width, height );
}
protected static void render( GL2 gl2, int width, int height ) {
gl2.glClear( GL.GL_COLOR_BUFFER_BIT );
// draw a triangle filling the window
gl2.glLoadIdentity();
gl2.glBegin( GL.GL_TRIANGLES );
gl2.glColor3f( 1, 0, 0 );
gl2.glVertex2f( 0, 0 );
gl2.glColor3f( 0, 1, 0 );
gl2.glVertex2f( width, 0 );
gl2.glColor3f( 0, 0, 1 );
gl2.glVertex2f( width / 2, height );
gl2.glEnd();
}
}