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" \
46 #define countof(x) (sizeof((x))/sizeof((*x)))
49 #define ABS(n) ((n)<0?-(n):(n))
51 #define SIGNOF(n) ((n)<0?-1:1)
53 #include "xlockmore.h"
56 #include "gltrackball.h"
59 #ifdef USE_GL /* whole file */
64 typedef struct metaball metaball;
68 GLXContext *glx_context;
70 trackball_state *trackball;
73 GLuint obj_dlist0; /* east-west cube faces */
74 GLuint obj_dlist1; /* north-south cube faces */
75 GLuint obj_dlist2; /* up-down cube faces */
76 GLuint obj_dlist3; /* spikes coming out of the cube's corners */
77 GLuint scene_dlist1; /* the cube, rotated and translated */
78 GLuint scene_dlist2; /* the spikes, rotated and translated */
79 int scene_polys1; /* polygons in scene, not counting texture overlay */
80 int scene_polys2; /* polygons in scene, not counting texture overlay */
83 unsigned int *tex_data;
96 } glblur_configuration;
98 static glblur_configuration *bps = NULL;
100 static char *do_spin;
101 static Bool do_wander;
104 static XrmOptionDescRec opts[] = {
105 { "-spin", ".spin", XrmoptionSepArg, 0 },
106 { "+spin", ".spin", XrmoptionNoArg, "" },
107 { "-blursize", ".blurSize", XrmoptionSepArg, 0 },
108 { "-wander", ".wander", XrmoptionNoArg, "True" },
109 { "+wander", ".wander", XrmoptionNoArg, "False" },
112 static argtype vars[] = {
113 {&do_spin, "spin", "Spin", DEF_SPIN, t_String},
114 {&do_wander, "wander", "Wander", DEF_WANDER, t_Bool},
115 {&blursize, "blurSize","BlurSize", DEF_BLURSIZE, t_Int},
118 ModeSpecOpt sws_opts = {countof(opts), opts, countof(vars), vars, NULL};
121 /* Window management, etc
124 reshape_glblur (ModeInfo *mi, int width, int height)
126 GLfloat h = (GLfloat) height / (GLfloat) width;
128 glViewport (0, 0, (GLint) width, (GLint) height);
130 glMatrixMode(GL_PROJECTION);
132 gluPerspective (30.0, 1/h, 1.0, 100.0);
134 glMatrixMode(GL_MODELVIEW);
136 gluLookAt( 0.0, 0.0, 8.0,
140 glClear(GL_COLOR_BUFFER_BIT);
145 /* Objects in the scene
149 generate_object (ModeInfo *mi)
151 glblur_configuration *bp = &bps[MI_SCREEN(mi)];
152 Bool wire = MI_IS_WIREFRAME (mi);
155 bp->scene_polys1 = 0;
156 bp->scene_polys2 = 0;
158 glNewList (bp->obj_dlist0, GL_COMPILE);
159 glBegin (wire ? GL_LINE_LOOP : GL_QUADS); /* front */
160 glNormal3f (0, 0, 1);
161 glTexCoord2f(1, 0); glVertex3f ( 0.5, -0.5, 0.5);
162 glTexCoord2f(0, 0); glVertex3f ( 0.5, 0.5, 0.5);
163 glTexCoord2f(0, 1); glVertex3f (-0.5, 0.5, 0.5);
164 glTexCoord2f(1, 1); glVertex3f (-0.5, -0.5, 0.5);
168 glBegin (wire ? GL_LINE_LOOP : GL_QUADS); /* back */
169 glNormal3f (0, 0, -1);
170 glTexCoord2f(0, 0); glVertex3f (-0.5, -0.5, -0.5);
171 glTexCoord2f(0, 1); glVertex3f (-0.5, 0.5, -0.5);
172 glTexCoord2f(1, 1); glVertex3f ( 0.5, 0.5, -0.5);
173 glTexCoord2f(1, 0); glVertex3f ( 0.5, -0.5, -0.5);
178 glNewList (bp->obj_dlist1, GL_COMPILE);
179 glBegin (wire ? GL_LINE_LOOP : GL_QUADS); /* left */
180 glNormal3f (-1, 0, 0);
181 glTexCoord2f(1, 1); glVertex3f (-0.5, 0.5, 0.5);
182 glTexCoord2f(1, 0); glVertex3f (-0.5, 0.5, -0.5);
183 glTexCoord2f(0, 0); glVertex3f (-0.5, -0.5, -0.5);
184 glTexCoord2f(0, 1); glVertex3f (-0.5, -0.5, 0.5);
188 glBegin (wire ? GL_LINE_LOOP : GL_QUADS); /* right */
189 glNormal3f (1, 0, 0);
190 glTexCoord2f(1, 1); glVertex3f ( 0.5, -0.5, -0.5);
191 glTexCoord2f(1, 0); glVertex3f ( 0.5, 0.5, -0.5);
192 glTexCoord2f(0, 0); glVertex3f ( 0.5, 0.5, 0.5);
193 glTexCoord2f(0, 1); glVertex3f ( 0.5, -0.5, 0.5);
198 glNewList (bp->obj_dlist2, GL_COMPILE);
199 glBegin (wire ? GL_LINE_LOOP : GL_QUADS); /* top */
200 glNormal3f (0, 1, 0);
201 glTexCoord2f(0, 0); glVertex3f ( 0.5, 0.5, 0.5);
202 glTexCoord2f(0, 1); glVertex3f ( 0.5, 0.5, -0.5);
203 glTexCoord2f(1, 1); glVertex3f (-0.5, 0.5, -0.5);
204 glTexCoord2f(1, 0); glVertex3f (-0.5, 0.5, 0.5);
208 glBegin (wire ? GL_LINE_LOOP : GL_QUADS); /* bottom */
209 glNormal3f (0, -1, 0);
210 glTexCoord2f(1, 0); glVertex3f (-0.5, -0.5, 0.5);
211 glTexCoord2f(0, 0); glVertex3f (-0.5, -0.5, -0.5);
212 glTexCoord2f(0, 1); glVertex3f ( 0.5, -0.5, -0.5);
213 glTexCoord2f(1, 1); glVertex3f ( 0.5, -0.5, 0.5);
218 glNewList (bp->obj_dlist3, GL_COMPILE);
221 glVertex3f(-s, 0, 0); glVertex3f(s, 0, 0); /* face spikes */
222 glVertex3f(0, -s, 0); glVertex3f(0, s, 0);
223 glVertex3f(0, 0, -s); glVertex3f(0, 0, s);
224 bp->scene_polys2 += 3;
229 glVertex3f(-s, -s, -s); glVertex3f( s, s, s); /* corner spikes */
230 glVertex3f(-s, -s, s); glVertex3f( s, s, -s);
231 glVertex3f(-s, s, -s); glVertex3f( s, -s, s);
232 glVertex3f( s, -s, -s); glVertex3f(-s, s, s);
233 bp->scene_polys2 += 4;
237 check_gl_error ("object generation");
242 init_texture (ModeInfo *mi)
244 glblur_configuration *bp = &bps[MI_SCREEN(mi)];
246 if (bp->tex_data) free (bp->tex_data);
250 bp->tex_data = (unsigned int *)
251 malloc (bp->tex_w * bp->tex_h * 4 * sizeof (unsigned int));
253 glGenTextures (1, &bp->texture);
254 glBindTexture (GL_TEXTURE_2D, bp->texture);
255 glTexImage2D (GL_TEXTURE_2D, 0, 4, 128, 128, 0,
257 /* GL_UNSIGNED_BYTE, */
258 GL_UNSIGNED_INT_8_8_8_8_REV,
260 glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
261 glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
266 render_scene_to_texture (ModeInfo *mi)
268 glblur_configuration *bp = &bps[MI_SCREEN(mi)];
270 glViewport (0, 0, bp->tex_w, bp->tex_h);
272 glCallList (bp->scene_dlist1);
273 glCallList (bp->scene_dlist2);
275 glBindTexture (GL_TEXTURE_2D, bp->texture);
276 glCopyTexImage2D (GL_TEXTURE_2D, 0, GL_LUMINANCE, 0, 0,
277 bp->tex_w, bp->tex_h, 0);
278 check_gl_error ("texture");
280 glViewport (0, 0, MI_WIDTH(mi), MI_HEIGHT(mi));
284 overlay_blur_texture (ModeInfo *mi)
286 glblur_configuration *bp = &bps[MI_SCREEN(mi)];
287 int w = MI_WIDTH (mi);
288 int h = MI_HEIGHT (mi);
289 int times = blursize;
291 GLfloat inc = 0.02 * (25.0 / times);
293 GLfloat spost = 0; /* starting texture coordinate offset */
294 GLfloat alpha_inc = 0.9 / times; /* transparency fade factor */
295 GLfloat alpha = 0.2; /* initial transparency */
297 glDisable (GL_TEXTURE_GEN_S);
298 glDisable (GL_TEXTURE_GEN_T);
300 glEnable (GL_TEXTURE_2D);
301 glDisable (GL_DEPTH_TEST);
302 glBlendFunc (GL_SRC_ALPHA,GL_ONE);
304 glBindTexture (GL_TEXTURE_2D, bp->texture);
307 /* switch to orthographic projection, saving both previous matrixes
308 on their respective stacks.
310 glMatrixMode (GL_PROJECTION);
313 glOrtho (0, w, h, 0, -1, 1);
314 glMatrixMode (GL_MODELVIEW);
319 alpha_inc = alpha / times;
321 mi->polygon_count = bp->scene_polys1 + bp->scene_polys2;
324 for (i = 0; i < times; i++)
326 glColor4f (1, 1, 1, alpha);
327 glTexCoord2f (0+spost, 1-spost); glVertex2f (0, 0);
328 glTexCoord2f (0+spost, 0+spost); glVertex2f (0, h);
329 glTexCoord2f (1-spost, 0+spost); glVertex2f (w, h);
330 glTexCoord2f (1-spost, 1-spost); glVertex2f (w, 0);
337 /* Switch back to perspective projection, restoring the saved matrixes
339 glMatrixMode (GL_PROJECTION);
341 glMatrixMode (GL_MODELVIEW);
344 glEnable (GL_DEPTH_TEST);
345 glDisable (GL_BLEND);
346 glDisable (GL_TEXTURE_2D);
347 glBindTexture (GL_TEXTURE_2D, 0);
352 /* Startup initialization
356 glblur_handle_event (ModeInfo *mi, XEvent *event)
358 glblur_configuration *bp = &bps[MI_SCREEN(mi)];
360 if (event->xany.type == ButtonPress &&
361 event->xbutton.button == Button1)
363 bp->button_down_p = True;
364 gltrackball_start (bp->trackball,
365 event->xbutton.x, event->xbutton.y,
366 MI_WIDTH (mi), MI_HEIGHT (mi));
369 else if (event->xany.type == ButtonRelease &&
370 event->xbutton.button == Button1)
372 bp->button_down_p = False;
375 else if (event->xany.type == ButtonPress &&
376 (event->xbutton.button == Button4 ||
377 event->xbutton.button == Button5))
379 gltrackball_mousewheel (bp->trackball, event->xbutton.button, 10,
380 !!event->xbutton.state);
383 else if (event->xany.type == MotionNotify &&
386 gltrackball_track (bp->trackball,
387 event->xmotion.x, event->xmotion.y,
388 MI_WIDTH (mi), MI_HEIGHT (mi));
397 init_glblur (ModeInfo *mi)
399 glblur_configuration *bp;
400 int wire = MI_IS_WIREFRAME(mi);
403 bps = (glblur_configuration *)
404 calloc (MI_NUM_SCREENS(mi), sizeof (glblur_configuration));
406 fprintf(stderr, "%s: out of memory\n", progname);
411 bp = &bps[MI_SCREEN(mi)];
413 bp->glx_context = init_GL(mi);
415 reshape_glblur (mi, MI_WIDTH(mi), MI_HEIGHT(mi));
419 GLfloat gamb[4]= {0.2, 0.2, 0.2, 1.0};
420 GLfloat pos[4] = {0.0, 5.0, 10.0, 1.0};
421 GLfloat amb[4] = {0.2, 0.2, 0.2, 1.0};
422 GLfloat dif[4] = {0.3, 0.3, 0.3, 1.0};
423 GLfloat spc[4] = {0.8, 0.8, 0.8, 1.0};
426 glEnable(GL_LIGHTING);
429 glEnable(GL_DEPTH_TEST);
430 glEnable(GL_CULL_FACE);
431 glEnable(GL_NORMALIZE);
432 glShadeModel(GL_SMOOTH);
434 glLightModelfv (GL_LIGHT_MODEL_AMBIENT, gamb);
436 glLightfv(GL_LIGHT0, GL_POSITION, pos);
437 glLightfv(GL_LIGHT0, GL_AMBIENT, amb);
438 glLightfv(GL_LIGHT0, GL_DIFFUSE, dif);
439 glLightfv(GL_LIGHT0, GL_SPECULAR, spc);
441 glEnable(GL_LIGHTING);
444 glMateriali(GL_FRONT, GL_SHININESS, shiny);
448 Bool spinx=False, spiny=False, spinz=False;
449 double spin_speed = 0.9;
450 double wander_speed = 0.06;
455 if (*s == 'x' || *s == 'X') spinx = True;
456 else if (*s == 'y' || *s == 'Y') spiny = True;
457 else if (*s == 'z' || *s == 'Z') spinz = True;
461 "%s: spin must contain only the characters X, Y, or Z (not \"%s\")\n",
468 bp->rot = make_rotator (spinx ? spin_speed : 0,
469 spiny ? spin_speed : 0,
470 spinz ? spin_speed : 0,
472 do_wander ? wander_speed : 0,
474 bp->trackball = gltrackball_init ();
477 if (blursize < 0) blursize = 0;
478 if (blursize > 200) blursize = 200;
481 bp->colors0 = (XColor *) calloc(bp->ncolors, sizeof(XColor));
482 bp->colors1 = (XColor *) calloc(bp->ncolors, sizeof(XColor));
483 bp->colors2 = (XColor *) calloc(bp->ncolors, sizeof(XColor));
484 bp->colors3 = (XColor *) calloc(bp->ncolors, sizeof(XColor));
485 make_smooth_colormap (0, 0, 0, bp->colors0, &bp->ncolors, False, 0, False);
486 make_smooth_colormap (0, 0, 0, bp->colors1, &bp->ncolors, False, 0, False);
487 make_smooth_colormap (0, 0, 0, bp->colors2, &bp->ncolors, False, 0, False);
488 make_smooth_colormap (0, 0, 0, bp->colors3, &bp->ncolors, False, 0, False);
491 bp->obj_dlist0 = glGenLists (1);
492 bp->obj_dlist1 = glGenLists (1);
493 bp->obj_dlist2 = glGenLists (1);
494 bp->obj_dlist3 = glGenLists (1);
495 bp->scene_dlist1 = glGenLists (1);
496 bp->scene_dlist2 = glGenLists (1);
499 generate_object (mi);
506 draw_glblur (ModeInfo *mi)
508 glblur_configuration *bp = &bps[MI_SCREEN(mi)];
509 Display *dpy = MI_DISPLAY(mi);
510 Window window = MI_WINDOW(mi);
512 static GLfloat color0[4] = {0.0, 0.0, 0.0, 1.0};
513 static GLfloat color1[4] = {0.0, 0.0, 0.0, 1.0};
514 static GLfloat color2[4] = {0.0, 0.0, 0.0, 1.0};
515 static GLfloat color3[4] = {0.0, 0.0, 0.0, 1.0};
516 static GLfloat spec[4] = {1.0, 1.0, 1.0, 1.0};
522 if (!bp->glx_context)
525 /* Decide what we're drawing
527 if (0 == (random() % 30))
529 bp->show_cube_p = (0 == (random() % 10));
530 bp->show_spikes_p = (0 == (random() % 20));
533 /* Select new colors for the various objects
535 color0[0] = bp->colors0[bp->ccolor].red / 65536.0;
536 color0[1] = bp->colors0[bp->ccolor].green / 65536.0;
537 color0[2] = bp->colors0[bp->ccolor].blue / 65536.0;
539 color1[0] = bp->colors1[bp->ccolor].red / 65536.0;
540 color1[1] = bp->colors1[bp->ccolor].green / 65536.0;
541 color1[2] = bp->colors1[bp->ccolor].blue / 65536.0;
543 color2[0] = bp->colors2[bp->ccolor].red / 65536.0;
544 color2[1] = bp->colors2[bp->ccolor].green / 65536.0;
545 color2[2] = bp->colors2[bp->ccolor].blue / 65536.0;
547 color3[0] = bp->colors3[bp->ccolor].red / 65536.0;
548 color3[1] = bp->colors3[bp->ccolor].green / 65536.0;
549 color3[2] = bp->colors3[bp->ccolor].blue / 65536.0;
552 if (bp->ccolor >= bp->ncolors) bp->ccolor = 0;
555 get_position (bp->rot, &px, &py, &pz, !bp->button_down_p);
556 get_rotation (bp->rot, &rx, &ry, &rz, !bp->button_down_p);
565 /* Generate scene_dlist1, which contains the box (not spikes),
566 rotated into position.
568 glNewList (bp->scene_dlist1, GL_COMPILE);
570 glMatrixMode (GL_MODELVIEW);
572 glTranslatef (px, py, pz);
573 gltrackball_rotate (bp->trackball);
574 glRotatef (rx, 1.0, 0.0, 0.0);
575 glRotatef (ry, 0.0, 1.0, 0.0);
576 glRotatef (rz, 0.0, 0.0, 1.0);
578 glMaterialfv (GL_FRONT_AND_BACK, GL_SPECULAR, spec);
580 glMaterialfv (GL_FRONT, GL_AMBIENT_AND_DIFFUSE, color0);
581 glCallList (bp->obj_dlist0);
583 glMaterialfv (GL_FRONT, GL_AMBIENT_AND_DIFFUSE, color1);
584 glCallList (bp->obj_dlist1);
586 glMaterialfv (GL_FRONT, GL_AMBIENT_AND_DIFFUSE, color2);
587 glCallList (bp->obj_dlist2);
594 /* Generate scene_dlist2, which contains the spikes (not box),
595 rotated into position.
597 glNewList (bp->scene_dlist2, GL_COMPILE);
599 glMatrixMode (GL_MODELVIEW);
601 glTranslatef (px, py, pz);
602 gltrackball_rotate (bp->trackball);
603 glRotatef (rx, 1.0, 0.0, 0.0);
604 glRotatef (ry, 0.0, 1.0, 0.0);
605 glRotatef (rz, 0.0, 0.0, 1.0);
607 glMaterialfv (GL_FRONT, GL_AMBIENT_AND_DIFFUSE, color3);
608 glCallList (bp->obj_dlist3);
615 glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
617 render_scene_to_texture (mi);
619 glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
621 if (bp->show_cube_p || bp->button_down_p)
623 glCallList (bp->scene_dlist1);
624 extra_polys += bp->scene_polys1;
626 if (bp->show_spikes_p || bp->button_down_p)
628 glCallList (bp->scene_dlist2);
629 extra_polys += bp->scene_polys2;
632 overlay_blur_texture (mi);
633 mi->polygon_count += extra_polys;
637 if (mi->fps_p) do_fps (mi);
640 glXSwapBuffers(dpy, window);