/t_backcompat/OpenGL/tutorial/lesson07.pl
Perl | 352 lines | 239 code | 79 blank | 34 comment | 28 complexity | 8aafb3097db8d6abd365436f8638a891 MD5 | raw file
1#!/usr/bin/perl 2# This code is based on the code by Jeff Molofee '99 3# and ported to SDL by Sam Lantinga '2000 4# Original ported to Perl/SDL by Wayne Keenan '2000 5# And updated by David Goehrig '02 6# 7# 8# Jeff's tutorials can be found at www.demonews.com/hosted/nehe 9 10use strict; 11use Getopt::Long; 12use Data::Dumper; 13use Benchmark; 14 15use SDL; 16use SDLx::App; 17use SDL::OpenGL; 18use SDL::Event; 19use SDL::Surface; 20use SDL::OpenGL; 21 22my $arg_screen_width = 640; 23my $arg_screen_height = 512; 24my $arg_fullscreen = 0; 25 26GetOptions( 27 "width:i" => \$arg_screen_width, 28 "height:i" => \$arg_screen_height, 29 "fullscreen!" => \$arg_fullscreen, 30) or die $!; 31 32############################################################ 33 34my $light = 0; 35 36my $xrot = 0; # x rotation 37my $yrot = 0; # y rotation 38my $xspeed = 0; # x rotation speed 39my $yspeed = 0; # y rotation speed 40 41my $z = -5.0; # depth into the screen. 42 43my $filter = 1; # Which Filter To Use (nearest/linear/mipmapped) */ 44 45main(); 46exit; 47 48sub main { 49 my $done = 0; 50 my $vidmode_flags = SDL_OPENGL; 51 52 $vidmode_flags |= SDL_FULLSCREEN if $arg_fullscreen; 53 54 my $app = SDLx::App->new( 55 -title => "Jeff Molofee's GL Code Tutorial ... NeHe '99", 56 -icon => "icon.png", 57 -flags => $vidmode_flags, 58 -width => $arg_screen_width, 59 -height => $arg_screen_height, 60 -opengl => 1, 61 ); 62 63 SDL::ShowCursor(0); 64 65 my $event = SDL::Event->new; 66 $event->set( SDL_SYSWMEVENT, SDL_IGNORE ); 67 68 InitGL( $arg_screen_width, $arg_screen_height ); 69 70 while ( not $done ) { 71 72 DrawGLScene(); 73 74 $app->sync(); 75 76 $event->pump; 77 $event->poll; 78 79 $done = 1 if ( $event->type == SDL_QUIT ); 80 81 if ( $event->type == SDL_KEYDOWN ) { 82 my $key = $event->key_sym; 83 84 $done = 1 if ( $key == SDLK_ESCAPE ); 85 86 if ( $key == SDLK_l ) { 87 printf( "Light was: %d\n", $light ); 88 $light = 89 $light 90 ? 0 91 : 1; # switch the current value of light, between 0 and 1. 92 printf( "Light is now: %d\n", $light ); 93 if ( !$light ) { 94 glDisable(GL_LIGHTING); 95 } else { 96 glEnable(GL_LIGHTING); 97 } 98 99 } 100 if ( $key == SDLK_f ) { 101 printf( "Filter was: %d\n", $filter ); 102 $filter = 1 + ( ($filter) % 3 ); 103 printf( "Filter is now: %d\n", $filter ); 104 } 105 106 #bit lax: 107 $z -= 0.02 if ( $key == SDLK_PAGEUP ); 108 $z += 0.02 if ( $key == SDLK_PAGEDOWN ); 109 $xspeed += 0.02 if ( $key == SDLK_UP ); 110 $xspeed -= 0.02 if ( $key == SDLK_DOWN ); 111 $yspeed -= 0.01 if ( $key == SDLK_LEFT ); 112 $yspeed += 0.01 if ( $key == SDLK_RIGHT ); 113 114 } 115 } 116} 117 118######################################################################### 119#Pretty much in original form, but 'Perlised' 120 121sub InitGL { 122 my ( $Width, $Height ) = @_; 123 124 glViewport( 0, 0, $Width, $Height ); 125 126 LoadGLTextures(); # Load The Texture(s) 127 128 glEnable(GL_TEXTURE_2D); # Enable Texture Mapping 129 130 glClearColor( 0.0, 0.0, 0.0, 0.0 ); # This Will Clear The Background Color To Black 131 glClearDepth(1.0); # Enables Clearing Of The Depth Buffer 132 glDepthFunc(GL_LESS); # The Type Of Depth Test To Do 133 glEnable(GL_DEPTH_TEST); # Enables Depth Testing 134 glShadeModel(GL_SMOOTH); # Enables Smooth Color Shading 135 136 glMatrixMode(GL_PROJECTION); 137 glLoadIdentity(); # Reset The Projection Matrix 138 139 gluPerspective( 45.0, $Width / $Height, 0.1, 100.0 ); # Calculate The Aspect Ratio Of The Window 140 141 glMatrixMode(GL_MODELVIEW); 142 143 my $LightAmbient = [ 0.5, 0.5, 0.5, 1.0 ]; # white ambient light at half intensity (rgba) */ 144 145 my $LightDiffuse = [ 1.0, 1.0, 1.0, 1.0 ]; # super bright, full intensity diffuse light. */ 146 147 my $LightPosition = [ 0.0, 0.0, 2.0, 1.0 ]; # position of light (x, y, z, (position of light)) */ 148 149 #hmm, undefine: 150 glLight( GL_LIGHT1, GL_AMBIENT, @$LightAmbient ); # add lighting. (ambient) 151 glLight( GL_LIGHT1, GL_DIFFUSE, @$LightDiffuse ); # add lighting. (diffuse). 152 glLight( GL_LIGHT1, GL_POSITION, @$LightPosition ); # set light position. 153 glEnable(GL_LIGHT1); # turn light 1 on. 154} 155 156# The main drawing function. 157sub DrawGLScene { 158 glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); # Clear The Screen And The Depth Buffer 159 glLoadIdentity(); # Reset The View 160 161 glTranslate( 0.0, 0.0, $z ); # move z units out from the screen. 162 163 glRotate( $xrot, 1.0, 0.0, 0.0 ); # Rotate On The X Axis 164 glRotate( $yrot, 0.0, 1.0, 0.0 ); # Rotate On The Y Axis 165 166 glBindTexture( GL_TEXTURE_2D, $filter ); # choose the texture to use. 167 168 glBegin(GL_QUADS); # begin drawing a cube 169 170 # Front Face (note that the texture's corners have to match the quad's corners) 171 glNormal( 0.0, 0.0, 1.0 ); # front face points out of the screen on z. 172 glTexCoord( 0.0, 0.0 ); 173 glVertex( -1.0, -1.0, 1.0 ); # Bottom Left Of The Texture and Quad 174 glTexCoord( 1.0, 0.0 ); 175 glVertex( 1.0, -1.0, 1.0 ); # Bottom Right Of The Texture and Quad 176 glTexCoord( 1.0, 1.0 ); 177 glVertex( 1.0, 1.0, 1.0 ); # Top Right Of The Texture and Quad 178 glTexCoord( 0.0, 1.0 ); 179 glVertex( -1.0, 1.0, 1.0 ); # Top Left Of The Texture and Quad 180 181 # Back Face 182 glNormal( 0.0, 0.0, -1.0 ); # back face points into the screen on z. 183 glTexCoord( 1.0, 0.0 ); 184 glVertex( -1.0, -1.0, -1.0 ); # Bottom Right Of The Texture and Quad 185 glTexCoord( 1.0, 1.0 ); 186 glVertex( -1.0, 1.0, -1.0 ); # Top Right Of The Texture and Quad 187 glTexCoord( 0.0, 1.0 ); 188 glVertex( 1.0, 1.0, -1.0 ); # Top Left Of The Texture and Quad 189 glTexCoord( 0.0, 0.0 ); 190 glVertex( 1.0, -1.0, -1.0 ); # Bottom Left Of The Texture and Quad 191 192 # Top Face 193 glNormal( 0.0, 1.0, 0.0 ); # top face points up on y. 194 glTexCoord( 0.0, 1.0 ); 195 glVertex( -1.0, 1.0, -1.0 ); # Top Left Of The Texture and Quad 196 glTexCoord( 0.0, 0.0 ); 197 glVertex( -1.0, 1.0, 1.0 ); # Bottom Left Of The Texture and Quad 198 glTexCoord( 1.0, 0.0 ); 199 glVertex( 1.0, 1.0, 1.0 ); # Bottom Right Of The Texture and Quad 200 glTexCoord( 1.0, 1.0 ); 201 glVertex( 1.0, 1.0, -1.0 ); # Top Right Of The Texture and Quad 202 203 # Bottom Face 204 glNormal( 0.0, -1.0, 0.0 ); # bottom face points down on y. 205 glTexCoord( 1.0, 1.0 ); 206 glVertex( -1.0, -1.0, -1.0 ); # Top Right Of The Texture and Quad 207 glTexCoord( 0.0, 1.0 ); 208 glVertex( 1.0, -1.0, -1.0 ); # Top Left Of The Texture and Quad 209 glTexCoord( 0.0, 0.0 ); 210 glVertex( 1.0, -1.0, 1.0 ); # Bottom Left Of The Texture and Quad 211 glTexCoord( 1.0, 0.0 ); 212 glVertex( -1.0, -1.0, 1.0 ); # Bottom Right Of The Texture and Quad 213 214 # Right face 215 glNormal( 1.0, 0.0, 0.0 ); # right face points right on x. 216 glTexCoord( 1.0, 0.0 ); 217 glVertex( 1.0, -1.0, -1.0 ); # Bottom Right Of The Texture and Quad 218 glTexCoord( 1.0, 1.0 ); 219 glVertex( 1.0, 1.0, -1.0 ); # Top Right Of The Texture and Quad 220 glTexCoord( 0.0, 1.0 ); 221 glVertex( 1.0, 1.0, 1.0 ); # Top Left Of The Texture and Quad 222 glTexCoord( 0.0, 0.0 ); 223 glVertex( 1.0, -1.0, 1.0 ); # Bottom Left Of The Texture and Quad 224 225 # Left Face 226 glNormal( -1.0, 0.0, 0.0 ); # left face points left on x. 227 glTexCoord( 0.0, 0.0 ); 228 glVertex( -1.0, -1.0, -1.0 ); # Bottom Left Of The Texture and Quad 229 glTexCoord( 1.0, 0.0 ); 230 glVertex( -1.0, -1.0, 1.0 ); # Bottom Right Of The Texture and Quad 231 glTexCoord( 1.0, 1.0 ); 232 glVertex( -1.0, 1.0, 1.0 ); # Top Right Of The Texture and Quad 233 glTexCoord( 0.0, 1.0 ); 234 glVertex( -1.0, 1.0, -1.0 ); # Top Left Of The Texture and Quad 235 236 glEnd(); # done with the polygon. 237 238 $xrot += $xspeed; # X Axis Rotation 239 $yrot += $yspeed; # Y Axis Rotation 240 241} 242 243sub LoadGLTextures { 244 245 # Load Texture 246 247 my ( $pixels, $width, $height, $size ) = ImageLoad("Data/crate.png"); 248 249 # Create Texture 250 251 glGenTextures(3); 252 253 # texture 1 (poor quality scaling) 254 glBindTexture( GL_TEXTURE_2D, 1 ); # 2d texture (x and y size) 255 256 glTexParameter( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST ); # cheap scaling when image bigger than texture 257 glTexParameter( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST ); # cheap scaling when image smalled than texture 258 259 # 2d texture, level of detail 0 (normal), 3 components (red, green, blue), x size from image, y size from image, 260 # border 0 (normal), rgb color data, unsigned byte data, and finally the data itself. 261 #glTexImage2D(GL_TEXTURE_2D, 0, 3, image1->w, image1->h, 0, GL_RGB, GL_UNSIGNED_BYTE, image1->pixels); 262 263 glTexImage2D( GL_TEXTURE_2D, 264 0, #level (0 normal, heighr is form mip-mapping) 265 3, #internal format (3=GL_RGB) 266 $width, $height, 267 0, # border 268 GL_RGB, #format RGB color data 269 GL_UNSIGNED_BYTE, #unsigned bye data 270 $pixels 271 ); #ptr to texture data 272 273 # texture 2 (linear scaling) 274 glBindTexture( GL_TEXTURE_2D, 2 ); # 2d texture (x and y size) 275 glTexParameter( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR ); # scale linearly when image bigger than texture 276 glTexParameter( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR ); # scale linearly when image smalled than texture 277 #glTexImage2D(GL_TEXTURE_2D, 0, 3, image1->w, image1->h, 0, GL_RGB, GL_UNSIGNED_BYTE, image1->pixels); 278 279 glTexImage2D( GL_TEXTURE_2D, 280 0, #level (0 normal, heighr is form mip-mapping) 281 3, #internal format (3=GL_RGB) 282 $width, $height, 283 0, # border 284 GL_RGB, #format RGB color data 285 GL_UNSIGNED_BYTE, #unsigned bye data 286 $pixels 287 ); #ptr to texture data 288 289 # texture 3 (mipmapped scaling) 290 glBindTexture( GL_TEXTURE_2D, 3 ); # 2d texture (x and y size) 291 glTexParameter( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR ); # scale linearly when image bigger than texture 292 glTexParameter( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, 293 GL_LINEAR_MIPMAP_NEAREST 294 ); # scale linearly + mipmap when image smalled than texture 295 #glTexImage2D(GL_TEXTURE_2D, 0, 3, image1->w, image1->h, 0, GL_RGB, GL_UNSIGNED_BYTE, image1->pixels); 296 297 glTexImage2D( GL_TEXTURE_2D, 298 0, #level (0 normal, heighr is form mip-mapping) 299 3, #internal format (3=GL_RGB) 300 $width, $height, 301 0, # border 302 GL_RGB, #format RGB color data 303 GL_UNSIGNED_BYTE, #unsigned bye data 304 $pixels 305 ); #ptr to texture data 306 307 # 2d texture, 3 colors, width, height, RGB in that order, byte data, and the data. 308 gluBuild2DMipmaps( GL_TEXTURE_2D, 3, $width, $height, GL_RGB, 309 GL_UNSIGNED_BYTE, $pixels 310 ); 311 312 my $glerr = glGetError(); 313 die "Problem setting up 2d Texture (dimensions not a power of 2?)):" . gluErrorString($glerr) . "\n" 314 if $glerr; 315 316} 317 318#somthing needs to keep the ref count alive for objects which represents data in C space (they have no ref count): 319my @ref = (); 320 321sub ImageLoad { 322 my $filename = shift; 323 324 my $surface = SDL::Surface->new( -name => $filename ); #makes use of SDL: BMP loader. 325 326 my $width = $surface->width(); 327 my $height = $surface->height(); 328 my $bytespp = $surface->bytes_per_pixel(); 329 my $size = $width * $height * $bytespp; 330 331 my $surface_pixels = $surface->pixels(); 332 my $surface_size = $width * $height * $surface->bytes_per_pixel(); 333 my $raw_pixels = $surface_pixels; 334 335 #do a conversion (the pixel data is accessable as a simple string) 336 337 my $pixels = $raw_pixels; 338 my $pre_conv = $pixels; #rotate image 180 degrees! 339 my $new_pixels = ""; 340 for ( my $y = 0; $y < $height; $y++ ) { 341 my $y_pos = $y * $width * $bytespp; #calculate offset into the image (a string) 342 my $row = substr( $pre_conv, $y_pos, $width * $bytespp ); #extract 1 pixel row 343 $row =~ s/\G(.)(.)(.)/$3$2$1/gms; #turn the BMP BGR order into OpenGL RGB order; 344 $new_pixels .= reverse $row; 345 } 346 347 $raw_pixels = $new_pixels; #put transformed data into C array. 348 push @ref, $raw_pixels, $surface; 349 350 #we could have created another SDL surface frm the '$raw_pixel's... oh well. 351 return ( $raw_pixels, $width, $height, $size ); 352}