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//========================================================================
// This is a small test application for GLFW.
// The program opens a window (640x480), and renders a spinning colored
// triangle (it is controlled with both the GLFW timer and the mouse).
//========================================================================
#include <stdio.h>
#include <stdlib.h>
#include <GL/glfw.h>
int main( void )
{
int width, height, x;
double t;
// Initialise GLFW
if( !glfwInit() )
{
fprintf( stderr, "Failed to initialize GLFW\n" );
exit( EXIT_FAILURE );
}
// Open a window and create its OpenGL context
if( !glfwOpenWindow( 640, 480, 0,0,0,0, 0,0, GLFW_WINDOW ) )
{
fprintf( stderr, "Failed to open GLFW window\n" );
glfwTerminate();
exit( EXIT_FAILURE );
}
glfwSetWindowTitle( "Spinning Triangle" );
// Ensure we can capture the escape key being pressed below
glfwEnable( GLFW_STICKY_KEYS );
// Enable vertical sync (on cards that support it)
glfwSwapInterval( 1 );
do
{
t = glfwGetTime();
glfwGetMousePos( &x, NULL );
// Get window size (may be different than the requested size)
glfwGetWindowSize( &width, &height );
// Special case: avoid division by zero below
height = height > 0 ? height : 1;
glViewport( 0, 0, width, height );
// Clear color buffer to black
glClearColor( 0.0f, 0.0f, 0.0f, 0.0f );
glClear( GL_COLOR_BUFFER_BIT );
// Select and setup the projection matrix
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
gluPerspective( 65.0f, (GLfloat)width/(GLfloat)height, 1.0f, 100.0f );
// Select and setup the modelview matrix
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
gluLookAt( 0.0f, 1.0f, 0.0f, // Eye-position
0.0f, 20.0f, 0.0f, // View-point
0.0f, 0.0f, 1.0f ); // Up-vector
// Draw a rotating colorful triangle
glTranslatef( 0.0f, 14.0f, 0.0f );
glRotatef( 0.3f*(GLfloat)x + (GLfloat)t*100.0f, 0.0f, 0.0f, 1.0f );
glBegin( GL_TRIANGLES );
glColor3f( 1.0f, 0.0f, 0.0f );
glVertex3f( -5.0f, 0.0f, -4.0f );
glColor3f( 0.0f, 1.0f, 0.0f );
glVertex3f( 5.0f, 0.0f, -4.0f );
glColor3f( 0.0f, 0.0f, 1.0f );
glVertex3f( 0.0f, 0.0f, 6.0f );
glEnd();
// Swap buffers
glfwSwapBuffers();
} // Check if the ESC key was pressed or the window was closed
while( glfwGetKey( GLFW_KEY_ESC ) != GLFW_PRESS &&
glfwGetWindowParam( GLFW_OPENED ) );
// Close OpenGL window and terminate GLFW
glfwTerminate();
exit( EXIT_SUCCESS );
}
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