// Two-Dimensional Sierpinski Gasket
// Generated using randomly selected vertices and bisection
#include "Angel.h"
//----------------------------------------------------------------------------
void
init( void )
{
// Specifiy the vertices for a triangle
vec4 vertices[3] = {
vec4( -1.0, -1.0, 0.0, 1.0 ), vec4( 0.0, 1.0, 0.0, 1.0 ), vec4( 1.0, -1.0, 0.0, 1.0 )
};
// Create a vertex array object
GLuint vao;
glGenVertexArrays( 1, &vao );
glBindVertexArray( vao );
// Create and initialize a buffer object
GLuint buffer;
glGenBuffers( 1, &buffer );
glBindBuffer( GL_ARRAY_BUFFER, buffer );
glBufferData( GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW );
// Load shaders and use the resulting shader program
GLuint program = InitShader( "vshader21.glsl", "fshader21.glsl" );
glUseProgram( program );
// Initialize the vertex position attribute from the vertex shader
GLuint loc = glGetAttribLocation( program, "vPosition" );
glEnableVertexAttribArray( loc );
glVertexAttribPointer( loc, 4, GL_FLOAT, GL_FALSE, 0,
BUFFER_OFFSET(0) );
glClearColor( 1.0, 1.0, 1.0, 1.0 ); // white background
}
//----------------------------------------------------------------------------
void
display( void )
{
glClear( GL_COLOR_BUFFER_BIT ); // clear the window
glDrawArrays( GL_TRIANGLES, 0, 3 ); // draw the points
glFlush();
}
//----------------------------------------------------------------------------
void
keyboard( unsigned char key, int x, int y )
{
switch ( key ) {
case 033:
exit( EXIT_SUCCESS );
break;
}
}
//----------------------------------------------------------------------------
int
main( int argc, char **argv )
{
glutInit( &argc, argv );
glutInitDisplayMode( GLUT_RGBA );
glutInitWindowSize( 512, 512 );
// If you are using freeglut, the next two lines will check if
// the code is truly 3.2. Otherwise, comment them out
glutInitContextVersion( 3, 2 );
glutInitContextProfile( GLUT_CORE_PROFILE );
glutCreateWindow( "Sierpinski Gasket" );
glewInit();
init();
glutDisplayFunc( display );
glutKeyboardFunc( keyboard );
glutMainLoop();
return 0;
}