rendered paste body/***************************************************************************
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU General Public License for more details. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program; if not, write to the *
* Free Software Foundation, Inc., *
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
***************************************************************************/
#include <SDL/SDL.h>
#include <GL/gl.h>
#include <GL/glu.h>
#include <stdio.h>
#include <stdlib.h>
static GLboolean should_rotate = GL_TRUE;
int makecube( int centerptx , int centerpty );
static void quit_tutorial( int code )
{
/*
* Quit SDL so we can release the fullscreen
* mode and restore the previous video settings,
* etc.
*/
SDL_Quit( );
/* Exit program. */
exit( code );
}
static void handle_key_down( SDL_keysym* keysym )
{
/*
* We're only interested if 'Esc' has
* been presssed.
*
* EXERCISE:
* Handle the arrow keys and have that change the
* viewing position/angle.
*/
switch( keysym->sym ) {
case SDLK_ESCAPE:
quit_tutorial( 0 );
break;
case SDLK_SPACE:
should_rotate = !should_rotate;
break;
default:
break;
}
}
static void process_events( void )
{
/* Our SDL event placeholder. */
SDL_Event event;
/* Grab all the events off the queue. */
while( SDL_PollEvent( &event ) ) {
switch( event.type ) {
case SDL_KEYDOWN:
/* Handle key presses. */
handle_key_down( &event.key.keysym );
break;
case SDL_QUIT:
/* Handle quit requests (like Ctrl-c). */
quit_tutorial( 0 );
break;
}
}
}
static void draw_screen( void )
{
/* Our angle of rotation. */
static float angle = 0.0f;
GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };
GLfloat light_position[] = { 1.0, 1.0, 1.0, 0.0 };
GLfloat diffuseMaterial[4] = { 0.5, 0.5, 0.5, 1.0 };
glClearColor (0.0, 0.0, 0.0, 0.0);
glShadeModel (GL_SMOOTH);
glEnable(GL_DEPTH_TEST);
glMaterialfv(GL_FRONT, GL_DIFFUSE, diffuseMaterial);
glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
glMaterialf(GL_FRONT, GL_SHININESS, 25.0);
glLightfv(GL_LIGHT0, GL_POSITION, light_position);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glColorMaterial(GL_FRONT, GL_DIFFUSE);
glEnable(GL_COLOR_MATERIAL);
/*
* EXERCISE:
* Replace this awful mess with vertex
* arrays and a call to glDrawElements.
*
* EXERCISE:
* After completing the above, change
* it to use compiled vertex arrays.
*
* EXERCISE:
* Verify my windings are correct here ;).
*/
static GLfloat v0[] = { -1.0f, -1.0f, 0.25f };
static GLfloat v1[] = { 1.0f, -1.0f, 0.25f };
static GLfloat v2[] = { 1.0f, 1.0f, 0.25f };
static GLfloat v3[] = { -1.0f, 1.0f, 0.25f };
static GLfloat v4[] = { -1.0f, -1.0f, -0.25f };
static GLfloat v5[] = { 1.0f, -1.0f, -0.25f };
static GLfloat v6[] = { 1.0f, 1.0f, -0.25f };
static GLfloat v7[] = { -1.0f, 1.0f, -0.25f };
static GLubyte red[] = { 255, 0, 0, 255 };
static GLubyte green[] = { 0, 255, 0, 255 };
static GLubyte blue[] = { 0, 0, 255, 255 };
static GLubyte white[] = { 255, 255, 255, 255 };
static GLubyte yellow[] = { 0, 255, 255, 255 };
static GLubyte black[] = { 0, 0, 0, 255 };
static GLubyte orange[] = { 255, 255, 0, 255 };
static GLubyte purple[] = { 255, 0, 255, 0 };
/* Clear the color and depth buffers. */
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
/* We don't want to modify the projection matrix. */
glMatrixMode( GL_MODELVIEW );
glLoadIdentity( );
/* Move down the z-axis. */
glTranslatef( 0.0, 0.0, -5.0 );
/* Rotate. */
glRotatef( angle, 0.0, 1.0, 0.0 );
if( should_rotate ) {
if( ++angle > 360.0f ) {
angle = 1.0f;
}
}
int makecube(1,1);
SDL_GL_SwapBuffers( );
}
int makecube( int centerptx , int centerpty )
{
//sqaures will be 2 units across and down.
//So centerptx=-3 will mean x1=-4, x2=-2
static GLfloat leftx = centerptx - 1;
static GLfloat topy = centerpty + 1;
static GLfloat rightx = centerptx + 1;
static GLfloat bottomy = centerpty - 1;
static GLfloat v10[] = { leftx, bottomy, 0.25f };
static GLfloat v11[] = { rightx, bottomy, 0.25f };
static GLfloat v12[] = { rightx, topy, 0.25f };
static GLfloat v13[] = { leftx, topy, 0.25f };
static GLfloat v14[] = { leftx, bottomy, -0.25f };
static GLfloat v15[] = { rightx, bottomy, -0.25f };
static GLfloat v16[] = { rightx, topy, -0.25f };
static GLfloat v17[] = { leftx, topy, -0.25f };
glBegin( GL_TRIANGLES );
static GLubyte blue[] = { 0, 0, 255, 255 };
glColor4ubv( blue );
glVertex3fv( v10 );
glVertex3fv( v11 );
glVertex3fv( v12 );
glVertex3fv( v10 );
glVertex3fv( v12 );
glVertex3fv( v13 );
glVertex3fv( v11 );
glVertex3fv( v15 );
glVertex3fv( v16 );
glVertex3fv( v11 );
glVertex3fv( v16 );
glVertex3fv( v12 );
glVertex3fv( v15 );
glVertex3fv( v14 );
glVertex3fv( v17 );
glVertex3fv( v15 );
glVertex3fv( v17 );
glVertex3fv( v16 );
glVertex3fv( v14 );
glVertex3fv( v10 );
glVertex3fv( v13 );
glVertex3fv( v14 );
glVertex3fv( v13 );
glVertex3fv( v17 );
glVertex3fv( v13 );
glVertex3fv( v12 );
glVertex3fv( v16 );
glVertex3fv( v13 );
glVertex3fv( v16 );
glVertex3fv( v17 );
glVertex3fv( v11 );
glVertex3fv( v10 );
glVertex3fv( v14 );
glVertex3fv( v11 );
glVertex3fv( v14 );
glVertex3fv( v15 );
glEnd( );
}
static void setup_opengl( int width, int height )
{
float ratio = (float) width / (float) height;
/* Our shading model--Gouraud (smooth). */
glShadeModel( GL_SMOOTH );
/* Culling. */
glCullFace( GL_BACK );
glFrontFace( GL_CCW );
glEnable( GL_CULL_FACE );
/* Set the clear color. */
glClearColor( 0, 0, 0, 0 );
/* Setup our viewport. */
glViewport( 0, 0, width, height );
/*
* Change to the projection matrix and set
* our viewing volume.
*/
glMatrixMode( GL_PROJECTION );
glLoadIdentity( );
/*
* EXERCISE:
* Replace this with a call to glFrustum.
*/
gluPerspective( 60.0, ratio, 1.0, 1024.0 );
}
int main( int argc, char* argv[] )
{
/* Information about the current video settings. */
const SDL_VideoInfo* info = NULL;
/* Dimensions of our window. */
int width = 0;
int height = 0;
/* Color depth in bits of our window. */
int bpp = 0;
/* Flags we will pass into SDL_SetVideoMode. */
int flags = 0;
/* First, initialize SDL's video subsystem. */
if( SDL_Init( SDL_INIT_VIDEO ) < 0 ) {
/* Failed, exit. */
fprintf( stderr, "Video initialization failed: %s\n",
SDL_GetError( ) );
quit_tutorial( 1 );
}
/* Let's get some video information. */
info = SDL_GetVideoInfo( );
if( !info ) {
/* This should probably never happen. */
fprintf( stderr, "Video query failed: %s\n",
SDL_GetError( ) );
quit_tutorial( 1 );
}
/*
* Set our width/height to 640/480 (you would
* of course let the user decide this in a normal
* app). We get the bpp we will request from
* the display. On X11, VidMode can't change
* resolution, so this is probably being overly
* safe. Under Win32, ChangeDisplaySettings
* can change the bpp.
*/
width = 640;
height = 480;
bpp = info->vfmt->BitsPerPixel;
/*
* Now, we want to setup our requested
* window attributes for our OpenGL window.
* We want *at least* 5 bits of red, green
* and blue. We also want at least a 16-bit
* depth buffer.
*
* The last thing we do is request a double
* buffered window. '1' turns on double
* buffering, '0' turns it off.
*
* Note that we do not use SDL_DOUBLEBUF in
* the flags to SDL_SetVideoMode. That does
* not affect the GL attribute state, only
* the standard 2D blitting setup.
*/
SDL_GL_SetAttribute( SDL_GL_RED_SIZE, 5 );
SDL_GL_SetAttribute( SDL_GL_GREEN_SIZE, 5 );
SDL_GL_SetAttribute( SDL_GL_BLUE_SIZE, 5 );
SDL_GL_SetAttribute( SDL_GL_DEPTH_SIZE, 16 );
SDL_GL_SetAttribute( SDL_GL_DOUBLEBUFFER, 1 );
/*
* We want to request that SDL provide us
* with an OpenGL window, in a fullscreen
* video mode.
*
* EXERCISE:
* Make starting windowed an option, and
* handle the resize events properly with
* glViewport.
*/
flags = SDL_OPENGL | SDL_FULLSCREEN;
/*
* Set the video mode
*/
if( SDL_SetVideoMode( width, height, bpp, flags ) == 0 ) {
/*
* This could happen for a variety of reasons,
* including DISPLAY not being set, the specified
* resolution not being available, etc.
*/
fprintf( stderr, "Video mode set failed: %s\n",
SDL_GetError( ) );
quit_tutorial( 1 );
}
/*
* At this point, we should have a properly setup
* double-buffered window for use with OpenGL.
*/
setup_opengl( width, height );
/*
* Now we want to begin our normal app process--
* an event loop with a lot of redrawing.
*/
while( 1 ) {
/* Process incoming events. */
process_events( );
/* Draw the screen. */
draw_screen( );
}
/*
* EXERCISE:
* Record timings using SDL_GetTicks() and
* and print out frames per second at program
* end.
*/
/* Never reached. */
return 0;
}