+++ /dev/null
-/* -*- Mode: C; tab-width: 4 -*- */
-/* cage --- the Impossible Cage, an Escher like scene. */
-
-#if !defined( lint ) && !defined( SABER )
-static const char sccsid[] = "@(#)cage.c 4.07 98/01/04 xlockmore";
-
-#endif
-
-#undef DEBUG_LISTS
-
-/*-
- * Permission to use, copy, modify, and distribute this software and its
- * documentation for any purpose and without fee is hereby granted,
- * provided that the above copyright notice appear in all copies and that
- * both that copyright notice and this permission notice appear in
- * supporting documentation.
- *
- * This file is provided AS IS with no warranties of any kind. The author
- * shall have no liability with respect to the infringement of copyrights,
- * trade secrets or any patents by this file or any part thereof. In no
- * event will the author be liable for any lost revenue or profits or
- * other special, indirect and consequential damages.
- *
- * The RotateAroundU() routine was adapted from the book
- * "Computer Graphics Principles and Practice
- * Foley - vanDam - Feiner - Hughes
- * Second Edition" Pag. 227, exercise 5.15.
- *
- * This mode shows some interesting scenes that are impossible OR very
- * wierd to build in the real universe. Much of the scenes are inspirated
- * on Mauritz Cornelis Escher's works which derivated the mode's name.
- * M.C. Escher (1898-1972) was a dutch artist and many people prefer to
- * say he was a mathematician.
- *
- * Thanks goes to Brian Paul for making it possible and inexpensive to use
- * OpenGL at home.
- *
- * Since I'm not a native English speaker, my apologies for any grammatical
- * mistake.
- *
- * My e-mail address is
- * m-vianna@usa.net
- *
- * Marcelo F. Vianna (Jun-01-1997)
- *
- * Revision History:
- * 01-Jan-98: Mode separated from escher and renamed
- * 08-Jun-97: New scene implemented: "Impossible Cage" based in a M.C. Escher's
- * painting with the same name (quite similar). The first GL mode
- * to use texture mapping.
- * The "Impossible Cage" scene doesn't use DEPTH BUFFER, the
- * wood planks are drawn consistently using GL_CULL_FACE, and
- * the painter's algorithm is used to sort the planks.
- * Marcelo F. Vianna.
- * 07-Jun-97: Speed ups in Moebius Strip using GL_CULL_FACE.
- * Marcelo F. Vianna.
- * 03-Jun-97: Initial Release (Only one scene: "Moebius Strip")
- * The Moebius Strip scene was inspirated in a M.C. Escher's
- * painting named Moebius Strip II in wich ants walk across a
- * Moebius Strip path, sometimes meeting each other and sometimes
- * being in "opposite faces" (note that the moebius strip has
- * only one face and one edge).
- * Marcelo F. Vianna.
- *
- */
-
-/*-
- * Texture mapping is only available on RGBA contexts, Mono and color index
- * visuals DO NOT support texture mapping in OpenGL.
- *
- * BUT Mesa do implements RGBA contexts in pseudo color visuals, so texture
- * mapping shuld work on PseudoColor, DirectColor, TrueColor using Mesa. Mono
- * is not officially supported for both OpenGL and Mesa, but seems to not crash
- * Mesa.
- *
- * In real OpenGL, PseudoColor DO NOT support texture map (as far as I know).
- */
-
-#include <X11/Intrinsic.h>
-
-#ifdef STANDALONE
-# define PROGCLASS "Cage"
-# define HACK_INIT init_cage
-# define HACK_DRAW draw_cage
-# define cage_opts xlockmore_opts
-# define DEFAULTS "*cycles: 1 \n" \
- "*delay: 1000 \n" \
- "*wireframe: False \n"
-# include "xlockmore.h" /* from the xscreensaver distribution */
-#else /* !STANDALONE */
-# include "xlock.h" /* from the xlockmore distribution */
-
-#endif /* !STANDALONE */
-
-#ifdef USE_GL
-
-
-#include <GL/glu.h>
-#include "e_textures.h"
-
-ModeSpecOpt cage_opts =
-{0, NULL, 0, NULL, NULL};
-
-#ifdef USE_MODULES
-ModStruct cage_description =
-{"cage", "init_cage", "draw_cage", "release_cage",
- "draw_cage", "change_cage", NULL, &cage_opts,
- 1000, 1, 1, 1, 1.0, 4, "",
- "Shows the Impossible Cage, an Escher-like GL scene", 0, NULL};
-
-#endif
-
-#define Scale4Window 0.3
-#define Scale4Iconic 0.4
-
-#define sqr(A) ((A)*(A))
-
-#ifndef Pi
-#define Pi M_PI
-#endif
-
-/*************************************************************************/
-
-typedef struct {
- GLint WindH, WindW;
- GLfloat step;
- int AreObjectsDefined[1];
- GLXContext *glx_context;
-} cagestruct;
-
-static float front_shininess[] =
-{60.0};
-static float front_specular[] =
-{0.7, 0.7, 0.7, 1.0};
-static float ambient[] =
-{0.0, 0.0, 0.0, 1.0};
-static float diffuse[] =
-{1.0, 1.0, 1.0, 1.0};
-static float position0[] =
-{1.0, 1.0, 1.0, 0.0};
-static float position1[] =
-{-1.0, -1.0, 1.0, 0.0};
-static float lmodel_ambient[] =
-{0.5, 0.5, 0.5, 1.0};
-static float lmodel_twoside[] =
-{GL_TRUE};
-
-static float MaterialWhite[] =
-{0.7, 0.7, 0.7, 1.0};
-
-static cagestruct *cage = NULL;
-static GLuint objects;
-
-#define ObjWoodPlank 0
-
-#define PlankWidth 3.0
-#define PlankHeight 0.35
-#define PlankThickness 0.15
-
-static void
-draw_woodplank(cagestruct * cp)
-{
- if (!cp->AreObjectsDefined[ObjWoodPlank]) {
- glNewList(objects + ObjWoodPlank, GL_COMPILE_AND_EXECUTE);
- glBegin(GL_QUADS);
- glNormal3f(0, 0, 1);
- glTexCoord2f(0, 0);
- glVertex3f(-PlankWidth, -PlankHeight, PlankThickness);
- glTexCoord2f(1, 0);
- glVertex3f(PlankWidth, -PlankHeight, PlankThickness);
- glTexCoord2f(1, 1);
- glVertex3f(PlankWidth, PlankHeight, PlankThickness);
- glTexCoord2f(0, 1);
- glVertex3f(-PlankWidth, PlankHeight, PlankThickness);
- glNormal3f(0, 0, -1);
- glTexCoord2f(0, 0);
- glVertex3f(-PlankWidth, PlankHeight, -PlankThickness);
- glTexCoord2f(1, 0);
- glVertex3f(PlankWidth, PlankHeight, -PlankThickness);
- glTexCoord2f(1, 1);
- glVertex3f(PlankWidth, -PlankHeight, -PlankThickness);
- glTexCoord2f(0, 1);
- glVertex3f(-PlankWidth, -PlankHeight, -PlankThickness);
- glNormal3f(0, 1, 0);
- glTexCoord2f(0, 0);
- glVertex3f(-PlankWidth, PlankHeight, PlankThickness);
- glTexCoord2f(1, 0);
- glVertex3f(PlankWidth, PlankHeight, PlankThickness);
- glTexCoord2f(1, 1);
- glVertex3f(PlankWidth, PlankHeight, -PlankThickness);
- glTexCoord2f(0, 1);
- glVertex3f(-PlankWidth, PlankHeight, -PlankThickness);
- glNormal3f(0, -1, 0);
- glTexCoord2f(0, 0);
- glVertex3f(-PlankWidth, -PlankHeight, -PlankThickness);
- glTexCoord2f(1, 0);
- glVertex3f(PlankWidth, -PlankHeight, -PlankThickness);
- glTexCoord2f(1, 1);
- glVertex3f(PlankWidth, -PlankHeight, PlankThickness);
- glTexCoord2f(0, 1);
- glVertex3f(-PlankWidth, -PlankHeight, PlankThickness);
- glNormal3f(1, 0, 0);
- glTexCoord2f(0, 0);
- glVertex3f(PlankWidth, -PlankHeight, PlankThickness);
- glTexCoord2f(1, 0);
- glVertex3f(PlankWidth, -PlankHeight, -PlankThickness);
- glTexCoord2f(1, 1);
- glVertex3f(PlankWidth, PlankHeight, -PlankThickness);
- glTexCoord2f(0, 1);
- glVertex3f(PlankWidth, PlankHeight, PlankThickness);
- glNormal3f(-1, 0, 0);
- glTexCoord2f(0, 0);
- glVertex3f(-PlankWidth, PlankHeight, PlankThickness);
- glTexCoord2f(1, 0);
- glVertex3f(-PlankWidth, PlankHeight, -PlankThickness);
- glTexCoord2f(1, 1);
- glVertex3f(-PlankWidth, -PlankHeight, -PlankThickness);
- glTexCoord2f(0, 1);
- glVertex3f(-PlankWidth, -PlankHeight, PlankThickness);
- glEnd();
- glEndList();
- cp->AreObjectsDefined[ObjWoodPlank] = 1;
-#ifdef DEBUG_LISTS
- (void) printf("WoodPlank drawn SLOWLY\n");
-#endif
- } else {
- glCallList(objects + ObjWoodPlank);
-#ifdef DEBUG_LISTS
- (void) printf("WoodPlank drawn quickly\n");
-#endif
- }
-}
-
-static void
-draw_impossiblecage(cagestruct * cp)
-{
- glPushMatrix();
- glRotatef(90, 0, 1, 0);
- glTranslatef(0.0, PlankHeight - PlankWidth, -PlankThickness - PlankWidth);
- draw_woodplank(cp);
- glPopMatrix();
- glPushMatrix();
- glRotatef(90, 0, 0, 1);
- glTranslatef(0.0, PlankHeight - PlankWidth, PlankWidth - PlankThickness);
- draw_woodplank(cp);
- glPopMatrix();
- glPushMatrix();
- glRotatef(90, 0, 1, 0);
- glTranslatef(0.0, PlankWidth - PlankHeight, -PlankThickness - PlankWidth);
- draw_woodplank(cp);
- glPopMatrix();
- glPushMatrix();
- glTranslatef(0.0, PlankWidth - PlankHeight, 3 * PlankThickness - PlankWidth);
- draw_woodplank(cp);
- glPopMatrix();
- glPushMatrix();
- glRotatef(90, 0, 0, 1);
- glTranslatef(0.0, PlankWidth - PlankHeight, PlankWidth - PlankThickness);
- draw_woodplank(cp);
- glPopMatrix();
- glPushMatrix();
- glTranslatef(0.0, PlankWidth - PlankHeight, PlankWidth - 3 * PlankThickness);
- draw_woodplank(cp);
- glPopMatrix();
- glPushMatrix();
- glTranslatef(0.0, PlankHeight - PlankWidth, 3 * PlankThickness - PlankWidth);
- draw_woodplank(cp);
- glPopMatrix();
- glPushMatrix();
- glRotatef(90, 0, 0, 1);
- glTranslatef(0.0, PlankHeight - PlankWidth, PlankThickness - PlankWidth);
- draw_woodplank(cp);
- glPopMatrix();
- glPushMatrix();
- glTranslatef(0.0, PlankHeight - PlankWidth, PlankWidth - 3 * PlankThickness);
- draw_woodplank(cp);
- glPopMatrix();
- glPushMatrix();
- glRotatef(90, 0, 1, 0);
- glTranslatef(0.0, PlankHeight - PlankWidth, PlankWidth + PlankThickness);
- draw_woodplank(cp);
- glPopMatrix();
- glPushMatrix();
- glRotatef(90, 0, 0, 1);
- glTranslatef(0.0, PlankWidth - PlankHeight, PlankThickness - PlankWidth);
- draw_woodplank(cp);
- glPopMatrix();
- glPushMatrix();
- glRotatef(90, 0, 1, 0);
- glTranslatef(0.0, PlankWidth - PlankHeight, PlankWidth + PlankThickness);
- draw_woodplank(cp);
- glPopMatrix();
-}
-
-static void
-reshape(ModeInfo * mi, int width, int height)
-{
- cagestruct *cp = &cage[MI_SCREEN(mi)];
-
- glViewport(0, 0, cp->WindW = (GLint) width, cp->WindH = (GLint) height);
- glMatrixMode(GL_PROJECTION);
- glLoadIdentity();
- glFrustum(-1.0, 1.0, -1.0, 1.0, 5.0, 15.0);
- glMatrixMode(GL_MODELVIEW);
- if (width >= 1024) {
- glLineWidth(3);
- glPointSize(3);
- } else if (width >= 512) {
- glLineWidth(2);
- glPointSize(2);
- } else {
- glLineWidth(1);
- glPointSize(1);
- }
- cp->AreObjectsDefined[ObjWoodPlank] = 0;
-}
-
-static void
-pinit(void)
-{
- glClearDepth(1.0);
- glClearColor(0.0, 0.0, 0.0, 1.0);
-
- glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);
- glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse);
- glLightfv(GL_LIGHT0, GL_POSITION, position0);
- glLightfv(GL_LIGHT1, GL_AMBIENT, ambient);
- glLightfv(GL_LIGHT1, GL_DIFFUSE, diffuse);
- glLightfv(GL_LIGHT1, GL_POSITION, position1);
- glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);
- glLightModelfv(GL_LIGHT_MODEL_TWO_SIDE, lmodel_twoside);
- glEnable(GL_LIGHTING);
- glEnable(GL_LIGHT0);
- glEnable(GL_LIGHT1);
- glEnable(GL_NORMALIZE);
- glFrontFace(GL_CCW);
- glCullFace(GL_BACK);
-
- /* cage */
- glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, MaterialWhite);
- glShadeModel(GL_FLAT);
- glDisable(GL_DEPTH_TEST);
- glEnable(GL_TEXTURE_2D);
- glEnable(GL_CULL_FACE);
-
- glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
- gluBuild2DMipmaps(GL_TEXTURE_2D, 3, WoodTextureWidth, WoodTextureHeight,
- GL_RGB, GL_UNSIGNED_BYTE, WoodTextureData);
- glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
- glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
- glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
- glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
- glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
-
- glMaterialfv(GL_FRONT_AND_BACK, GL_SHININESS, front_shininess);
- glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, front_specular);
-}
-
-void
-init_cage(ModeInfo * mi)
-{
- int screen = MI_SCREEN(mi);
- cagestruct *cp;
-
- if (cage == NULL) {
- if ((cage = (cagestruct *) calloc(MI_NUM_SCREENS(mi),
- sizeof (cagestruct))) == NULL)
- return;
- }
- cp = &cage[screen];
- cp->step = NRAND(90);
-
- if ((cp->glx_context = init_GL(mi)) != NULL) {
-
- reshape(mi, MI_WIDTH(mi), MI_HEIGHT(mi));
- glDrawBuffer(GL_BACK);
- if (!glIsList(objects))
- objects = glGenLists(1);
- pinit();
- } else {
- MI_CLEARWINDOW(mi);
- }
-}
-
-void
-draw_cage(ModeInfo * mi)
-{
- cagestruct *cp = &cage[MI_SCREEN(mi)];
-
- Display *display = MI_DISPLAY(mi);
- Window window = MI_WINDOW(mi);
-
- MI_IS_DRAWN(mi) = True;
-
- if (!cp->glx_context)
- return;
-
- glXMakeCurrent(display, window, *(cp->glx_context));
-
- glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-
- glPushMatrix();
-
- glTranslatef(0.0, 0.0, -10.0);
-
- if (!MI_IS_ICONIC(mi)) {
- glScalef(Scale4Window * cp->WindH / cp->WindW, Scale4Window, Scale4Window);
- } else {
- glScalef(Scale4Iconic * cp->WindH / cp->WindW, Scale4Iconic, Scale4Iconic);
- }
-
- /* cage */
- glRotatef(cp->step * 100, 0, 0, 1);
- glRotatef(25 + cos(cp->step * 5) * 6, 1, 0, 0);
- glRotatef(204.5 - sin(cp->step * 5) * 8, 0, 1, 0);
- draw_impossiblecage(cp);
-
- glPopMatrix();
-
- glFlush();
-
- glXSwapBuffers(display, window);
-
- cp->step += 0.025;
-}
-
-void
-change_cage(ModeInfo * mi)
-{
- cagestruct *cp = &cage[MI_SCREEN(mi)];
-
- if (!cp->glx_context)
- return;
-
- glXMakeCurrent(MI_DISPLAY(mi), MI_WINDOW(mi), *(cp->glx_context));
- pinit();
-}
-
-void
-release_cage(ModeInfo * mi)
-{
- if (cage != NULL) {
- (void) free((void *) cage);
- cage = NULL;
- }
- if (glIsList(objects)) {
- glDeleteLists(objects, 1);
- }
- FreeAllGL(mi);
-}
-
-#endif
projects / xscreensaver / blobdiff