1 /* glblur --- radial blur using GL textures
2 * Copyright (c) 2002-2004 Jamie Zawinski <jwz@jwz.org>
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that
7 * copyright notice and this permission notice appear in supporting
8 * documentation. No representations are made about the suitability of this
9 * software for any purpose. It is provided "as is" without express or
12 * This program draws a box and a few line segments, and generates a flowing
13 * radial blur outward from it -- this causes flowing field effects.
14 * It does this by rendering the scene into a small texture, then repeatedly
15 * rendering increasingly-enlarged and increasingly-transparent versions of
16 * that texture onto the frame buffer.
18 * As such, it's quite graphics intensive -- don't bother trying to run this
19 * if you don't have hardware-accelerated texture support.
21 * Inspired by Dario Corno's Radial Blur tutorial:
22 * http://nehe.gamedev.net/tutorials/lesson.asp?l=36
25 #include <X11/Intrinsic.h>
27 extern XtAppContext app;
29 #define PROGCLASS "GLBlur"
30 #define HACK_INIT init_glblur
31 #define HACK_DRAW draw_glblur
32 #define HACK_RESHAPE reshape_glblur
33 #define HACK_HANDLE_EVENT glblur_handle_event
34 #define EVENT_MASK PointerMotionMask
35 #define sws_opts xlockmore_opts
37 #define DEF_SPIN "XYZ"
38 #define DEF_WANDER "True"
39 #define DEF_BLURSIZE "15"
41 #define DEFAULTS "*delay: 10000 \n" \
42 "*showFPS: False \n" \
43 "*fpsSolid: True \n" \
44 "*wireframe: False \n" \
48 #define countof(x) (sizeof((x))/sizeof((*x)))
51 #define ABS(n) ((n)<0?-(n):(n))
53 #define SIGNOF(n) ((n)<0?-1:1)
55 #include "xlockmore.h"
58 #include "gltrackball.h"
61 #ifdef USE_GL /* whole file */
66 typedef struct metaball metaball;
70 GLXContext *glx_context;
72 trackball_state *trackball;
75 GLuint obj_dlist0; /* east-west cube faces */
76 GLuint obj_dlist1; /* north-south cube faces */
77 GLuint obj_dlist2; /* up-down cube faces */
78 GLuint obj_dlist3; /* spikes coming out of the cube's corners */
79 GLuint scene_dlist1; /* the cube, rotated and translated */
80 GLuint scene_dlist2; /* the spikes, rotated and translated */
81 int scene_polys1; /* polygons in scene, not counting texture overlay */
82 int scene_polys2; /* polygons in scene, not counting texture overlay */
85 unsigned int *tex_data;
98 } glblur_configuration;
100 static glblur_configuration *bps = NULL;
102 static char *do_spin;
103 static Bool do_wander;
106 static XrmOptionDescRec opts[] = {
107 { "-spin", ".spin", XrmoptionSepArg, 0 },
108 { "+spin", ".spin", XrmoptionNoArg, "" },
109 { "-blursize", ".blurSize", XrmoptionSepArg, 0 },
110 { "-wander", ".wander", XrmoptionNoArg, "True" },
111 { "+wander", ".wander", XrmoptionNoArg, "False" },
114 static argtype vars[] = {
115 {&do_spin, "spin", "Spin", DEF_SPIN, t_String},
116 {&do_wander, "wander", "Wander", DEF_WANDER, t_Bool},
117 {&blursize, "blurSize","BlurSize", DEF_BLURSIZE, t_Int},
120 ModeSpecOpt sws_opts = {countof(opts), opts, countof(vars), vars, NULL};
123 /* Window management, etc
126 reshape_glblur (ModeInfo *mi, int width, int height)
128 GLfloat h = (GLfloat) height / (GLfloat) width;
130 glViewport (0, 0, (GLint) width, (GLint) height);
132 glMatrixMode(GL_PROJECTION);
134 gluPerspective (30.0, 1/h, 1.0, 100.0);
136 glMatrixMode(GL_MODELVIEW);
138 gluLookAt( 0.0, 0.0, 8.0,
142 glClear(GL_COLOR_BUFFER_BIT);
147 /* Objects in the scene
151 generate_object (ModeInfo *mi)
153 glblur_configuration *bp = &bps[MI_SCREEN(mi)];
154 Bool wire = MI_IS_WIREFRAME (mi);
157 bp->scene_polys1 = 0;
158 bp->scene_polys2 = 0;
160 glNewList (bp->obj_dlist0, GL_COMPILE);
161 glBegin (wire ? GL_LINE_LOOP : GL_QUADS); /* front */
162 glNormal3f (0, 0, 1);
163 glTexCoord2f(1, 0); glVertex3f ( 0.5, -0.5, 0.5);
164 glTexCoord2f(0, 0); glVertex3f ( 0.5, 0.5, 0.5);
165 glTexCoord2f(0, 1); glVertex3f (-0.5, 0.5, 0.5);
166 glTexCoord2f(1, 1); glVertex3f (-0.5, -0.5, 0.5);
170 glBegin (wire ? GL_LINE_LOOP : GL_QUADS); /* back */
171 glNormal3f (0, 0, -1);
172 glTexCoord2f(0, 0); glVertex3f (-0.5, -0.5, -0.5);
173 glTexCoord2f(0, 1); glVertex3f (-0.5, 0.5, -0.5);
174 glTexCoord2f(1, 1); glVertex3f ( 0.5, 0.5, -0.5);
175 glTexCoord2f(1, 0); glVertex3f ( 0.5, -0.5, -0.5);
180 glNewList (bp->obj_dlist1, GL_COMPILE);
181 glBegin (wire ? GL_LINE_LOOP : GL_QUADS); /* left */
182 glNormal3f (-1, 0, 0);
183 glTexCoord2f(1, 1); glVertex3f (-0.5, 0.5, 0.5);
184 glTexCoord2f(1, 0); glVertex3f (-0.5, 0.5, -0.5);
185 glTexCoord2f(0, 0); glVertex3f (-0.5, -0.5, -0.5);
186 glTexCoord2f(0, 1); glVertex3f (-0.5, -0.5, 0.5);
190 glBegin (wire ? GL_LINE_LOOP : GL_QUADS); /* right */
191 glNormal3f (1, 0, 0);
192 glTexCoord2f(1, 1); glVertex3f ( 0.5, -0.5, -0.5);
193 glTexCoord2f(1, 0); glVertex3f ( 0.5, 0.5, -0.5);
194 glTexCoord2f(0, 0); glVertex3f ( 0.5, 0.5, 0.5);
195 glTexCoord2f(0, 1); glVertex3f ( 0.5, -0.5, 0.5);
200 glNewList (bp->obj_dlist2, GL_COMPILE);
201 glBegin (wire ? GL_LINE_LOOP : GL_QUADS); /* top */
202 glNormal3f (0, 1, 0);
203 glTexCoord2f(0, 0); glVertex3f ( 0.5, 0.5, 0.5);
204 glTexCoord2f(0, 1); glVertex3f ( 0.5, 0.5, -0.5);
205 glTexCoord2f(1, 1); glVertex3f (-0.5, 0.5, -0.5);
206 glTexCoord2f(1, 0); glVertex3f (-0.5, 0.5, 0.5);
210 glBegin (wire ? GL_LINE_LOOP : GL_QUADS); /* bottom */
211 glNormal3f (0, -1, 0);
212 glTexCoord2f(1, 0); glVertex3f (-0.5, -0.5, 0.5);
213 glTexCoord2f(0, 0); glVertex3f (-0.5, -0.5, -0.5);
214 glTexCoord2f(0, 1); glVertex3f ( 0.5, -0.5, -0.5);
215 glTexCoord2f(1, 1); glVertex3f ( 0.5, -0.5, 0.5);
220 glNewList (bp->obj_dlist3, GL_COMPILE);
223 glVertex3f(-s, 0, 0); glVertex3f(s, 0, 0); /* face spikes */
224 glVertex3f(0, -s, 0); glVertex3f(0, s, 0);
225 glVertex3f(0, 0, -s); glVertex3f(0, 0, s);
226 bp->scene_polys2 += 3;
231 glVertex3f(-s, -s, -s); glVertex3f( s, s, s); /* corner spikes */
232 glVertex3f(-s, -s, s); glVertex3f( s, s, -s);
233 glVertex3f(-s, s, -s); glVertex3f( s, -s, s);
234 glVertex3f( s, -s, -s); glVertex3f(-s, s, s);
235 bp->scene_polys2 += 4;
239 check_gl_error ("object generation");
244 init_texture (ModeInfo *mi)
246 glblur_configuration *bp = &bps[MI_SCREEN(mi)];
248 if (bp->tex_data) free (bp->tex_data);
252 bp->tex_data = (unsigned int *)
253 malloc (bp->tex_w * bp->tex_h * 4 * sizeof (unsigned int));
255 glGenTextures (1, &bp->texture);
256 glBindTexture (GL_TEXTURE_2D, bp->texture);
257 glTexImage2D (GL_TEXTURE_2D, 0, 4, 128, 128, 0,
259 /* GL_UNSIGNED_BYTE, */
260 GL_UNSIGNED_INT_8_8_8_8_REV,
262 glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
263 glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
268 render_scene_to_texture (ModeInfo *mi)
270 glblur_configuration *bp = &bps[MI_SCREEN(mi)];
272 glViewport (0, 0, bp->tex_w, bp->tex_h);
274 glCallList (bp->scene_dlist1);
275 glCallList (bp->scene_dlist2);
277 glBindTexture (GL_TEXTURE_2D, bp->texture);
278 glCopyTexImage2D (GL_TEXTURE_2D, 0, GL_LUMINANCE, 0, 0,
279 bp->tex_w, bp->tex_h, 0);
280 check_gl_error ("texture");
282 glViewport (0, 0, MI_WIDTH(mi), MI_HEIGHT(mi));
286 overlay_blur_texture (ModeInfo *mi)
288 glblur_configuration *bp = &bps[MI_SCREEN(mi)];
289 int w = MI_WIDTH (mi);
290 int h = MI_HEIGHT (mi);
291 int times = blursize;
293 GLfloat inc = 0.02 * (25.0 / times);
295 GLfloat spost = 0; /* starting texture coordinate offset */
296 GLfloat alpha_inc = 0.9 / times; /* transparency fade factor */
297 GLfloat alpha = 0.2; /* initial transparency */
299 glDisable (GL_TEXTURE_GEN_S);
300 glDisable (GL_TEXTURE_GEN_T);
302 glEnable (GL_TEXTURE_2D);
303 glDisable (GL_DEPTH_TEST);
304 glBlendFunc (GL_SRC_ALPHA,GL_ONE);
306 glBindTexture (GL_TEXTURE_2D, bp->texture);
309 /* switch to orthographic projection, saving both previous matrixes
310 on their respective stacks.
312 glMatrixMode (GL_PROJECTION);
315 glOrtho (0, w, h, 0, -1, 1);
316 glMatrixMode (GL_MODELVIEW);
321 alpha_inc = alpha / times;
323 mi->polygon_count = bp->scene_polys1 + bp->scene_polys2;
326 for (i = 0; i < times; i++)
328 glColor4f (1, 1, 1, alpha);
329 glTexCoord2f (0+spost, 1-spost); glVertex2f (0, 0);
330 glTexCoord2f (0+spost, 0+spost); glVertex2f (0, h);
331 glTexCoord2f (1-spost, 0+spost); glVertex2f (w, h);
332 glTexCoord2f (1-spost, 1-spost); glVertex2f (w, 0);
339 /* Switch back to perspective projection, restoring the saved matrixes
341 glMatrixMode (GL_PROJECTION);
343 glMatrixMode (GL_MODELVIEW);
346 glEnable (GL_DEPTH_TEST);
347 glDisable (GL_BLEND);
348 glDisable (GL_TEXTURE_2D);
349 glBindTexture (GL_TEXTURE_2D, 0);
354 /* Startup initialization
358 glblur_handle_event (ModeInfo *mi, XEvent *event)
360 glblur_configuration *bp = &bps[MI_SCREEN(mi)];
362 if (event->xany.type == ButtonPress &&
363 event->xbutton.button == Button1)
365 bp->button_down_p = True;
366 gltrackball_start (bp->trackball,
367 event->xbutton.x, event->xbutton.y,
368 MI_WIDTH (mi), MI_HEIGHT (mi));
371 else if (event->xany.type == ButtonRelease &&
372 event->xbutton.button == Button1)
374 bp->button_down_p = False;
377 else if (event->xany.type == ButtonPress &&
378 (event->xbutton.button == Button4 ||
379 event->xbutton.button == Button5))
381 gltrackball_mousewheel (bp->trackball, event->xbutton.button, 10,
382 !!event->xbutton.state);
385 else if (event->xany.type == MotionNotify &&
388 gltrackball_track (bp->trackball,
389 event->xmotion.x, event->xmotion.y,
390 MI_WIDTH (mi), MI_HEIGHT (mi));
399 init_glblur (ModeInfo *mi)
401 glblur_configuration *bp;
402 int wire = MI_IS_WIREFRAME(mi);
405 bps = (glblur_configuration *)
406 calloc (MI_NUM_SCREENS(mi), sizeof (glblur_configuration));
408 fprintf(stderr, "%s: out of memory\n", progname);
413 bp = &bps[MI_SCREEN(mi)];
415 bp->glx_context = init_GL(mi);
417 reshape_glblur (mi, MI_WIDTH(mi), MI_HEIGHT(mi));
421 GLfloat gamb[4]= {0.2, 0.2, 0.2, 1.0};
422 GLfloat pos[4] = {0.0, 5.0, 10.0, 1.0};
423 GLfloat amb[4] = {0.2, 0.2, 0.2, 1.0};
424 GLfloat dif[4] = {0.3, 0.3, 0.3, 1.0};
425 GLfloat spc[4] = {0.8, 0.8, 0.8, 1.0};
428 glEnable(GL_LIGHTING);
431 glEnable(GL_DEPTH_TEST);
432 glEnable(GL_CULL_FACE);
433 glEnable(GL_NORMALIZE);
434 glShadeModel(GL_SMOOTH);
436 glLightModelfv (GL_LIGHT_MODEL_AMBIENT, gamb);
438 glLightfv(GL_LIGHT0, GL_POSITION, pos);
439 glLightfv(GL_LIGHT0, GL_AMBIENT, amb);
440 glLightfv(GL_LIGHT0, GL_DIFFUSE, dif);
441 glLightfv(GL_LIGHT0, GL_SPECULAR, spc);
443 glEnable(GL_LIGHTING);
446 glMateriali(GL_FRONT, GL_SHININESS, shiny);
450 Bool spinx=False, spiny=False, spinz=False;
451 double spin_speed = 0.9;
452 double wander_speed = 0.06;
457 if (*s == 'x' || *s == 'X') spinx = True;
458 else if (*s == 'y' || *s == 'Y') spiny = True;
459 else if (*s == 'z' || *s == 'Z') spinz = True;
463 "%s: spin must contain only the characters X, Y, or Z (not \"%s\")\n",
470 bp->rot = make_rotator (spinx ? spin_speed : 0,
471 spiny ? spin_speed : 0,
472 spinz ? spin_speed : 0,
474 do_wander ? wander_speed : 0,
476 bp->trackball = gltrackball_init ();
479 if (blursize < 0) blursize = 0;
480 if (blursize > 200) blursize = 200;
483 bp->colors0 = (XColor *) calloc(bp->ncolors, sizeof(XColor));
484 bp->colors1 = (XColor *) calloc(bp->ncolors, sizeof(XColor));
485 bp->colors2 = (XColor *) calloc(bp->ncolors, sizeof(XColor));
486 bp->colors3 = (XColor *) calloc(bp->ncolors, sizeof(XColor));
487 make_smooth_colormap (0, 0, 0, bp->colors0, &bp->ncolors, False, 0, False);
488 make_smooth_colormap (0, 0, 0, bp->colors1, &bp->ncolors, False, 0, False);
489 make_smooth_colormap (0, 0, 0, bp->colors2, &bp->ncolors, False, 0, False);
490 make_smooth_colormap (0, 0, 0, bp->colors3, &bp->ncolors, False, 0, False);
493 bp->obj_dlist0 = glGenLists (1);
494 bp->obj_dlist1 = glGenLists (1);
495 bp->obj_dlist2 = glGenLists (1);
496 bp->obj_dlist3 = glGenLists (1);
497 bp->scene_dlist1 = glGenLists (1);
498 bp->scene_dlist2 = glGenLists (1);
501 generate_object (mi);
508 draw_glblur (ModeInfo *mi)
510 glblur_configuration *bp = &bps[MI_SCREEN(mi)];
511 Display *dpy = MI_DISPLAY(mi);
512 Window window = MI_WINDOW(mi);
514 static GLfloat color0[4] = {0.0, 0.0, 0.0, 1.0};
515 static GLfloat color1[4] = {0.0, 0.0, 0.0, 1.0};
516 static GLfloat color2[4] = {0.0, 0.0, 0.0, 1.0};
517 static GLfloat color3[4] = {0.0, 0.0, 0.0, 1.0};
518 static GLfloat spec[4] = {1.0, 1.0, 1.0, 1.0};
524 if (!bp->glx_context)
527 /* Decide what we're drawing
529 if (0 == (random() % 30))
531 bp->show_cube_p = (0 == (random() % 10));
532 bp->show_spikes_p = (0 == (random() % 20));
535 /* Select new colors for the various objects
537 color0[0] = bp->colors0[bp->ccolor].red / 65536.0;
538 color0[1] = bp->colors0[bp->ccolor].green / 65536.0;
539 color0[2] = bp->colors0[bp->ccolor].blue / 65536.0;
541 color1[0] = bp->colors1[bp->ccolor].red / 65536.0;
542 color1[1] = bp->colors1[bp->ccolor].green / 65536.0;
543 color1[2] = bp->colors1[bp->ccolor].blue / 65536.0;
545 color2[0] = bp->colors2[bp->ccolor].red / 65536.0;
546 color2[1] = bp->colors2[bp->ccolor].green / 65536.0;
547 color2[2] = bp->colors2[bp->ccolor].blue / 65536.0;
549 color3[0] = bp->colors3[bp->ccolor].red / 65536.0;
550 color3[1] = bp->colors3[bp->ccolor].green / 65536.0;
551 color3[2] = bp->colors3[bp->ccolor].blue / 65536.0;
554 if (bp->ccolor >= bp->ncolors) bp->ccolor = 0;
557 get_position (bp->rot, &px, &py, &pz, !bp->button_down_p);
558 get_rotation (bp->rot, &rx, &ry, &rz, !bp->button_down_p);
567 /* Generate scene_dlist1, which contains the box (not spikes),
568 rotated into position.
570 glNewList (bp->scene_dlist1, GL_COMPILE);
572 glMatrixMode (GL_MODELVIEW);
574 glTranslatef (px, py, pz);
575 gltrackball_rotate (bp->trackball);
576 glRotatef (rx, 1.0, 0.0, 0.0);
577 glRotatef (ry, 0.0, 1.0, 0.0);
578 glRotatef (rz, 0.0, 0.0, 1.0);
580 glMaterialfv (GL_FRONT_AND_BACK, GL_SPECULAR, spec);
582 glMaterialfv (GL_FRONT, GL_AMBIENT_AND_DIFFUSE, color0);
583 glCallList (bp->obj_dlist0);
585 glMaterialfv (GL_FRONT, GL_AMBIENT_AND_DIFFUSE, color1);
586 glCallList (bp->obj_dlist1);
588 glMaterialfv (GL_FRONT, GL_AMBIENT_AND_DIFFUSE, color2);
589 glCallList (bp->obj_dlist2);
596 /* Generate scene_dlist2, which contains the spikes (not box),
597 rotated into position.
599 glNewList (bp->scene_dlist2, GL_COMPILE);
601 glMatrixMode (GL_MODELVIEW);
603 glTranslatef (px, py, pz);
604 gltrackball_rotate (bp->trackball);
605 glRotatef (rx, 1.0, 0.0, 0.0);
606 glRotatef (ry, 0.0, 1.0, 0.0);
607 glRotatef (rz, 0.0, 0.0, 1.0);
609 glMaterialfv (GL_FRONT, GL_AMBIENT_AND_DIFFUSE, color3);
610 glCallList (bp->obj_dlist3);
617 glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
619 render_scene_to_texture (mi);
621 glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
623 if (bp->show_cube_p || bp->button_down_p)
625 glCallList (bp->scene_dlist1);
626 extra_polys += bp->scene_polys1;
628 if (bp->show_spikes_p || bp->button_down_p)
630 glCallList (bp->scene_dlist2);
631 extra_polys += bp->scene_polys2;
634 overlay_blur_texture (mi);
635 mi->polygon_count += extra_polys;
639 if (mi->fps_p) do_fps (mi);
642 glXSwapBuffers(dpy, window);