Material für Praktikumsversuch 2: egal.txt, orbit-1.c, textured-spheres.[ch], Texturen

20171106/egal.txt

-GNU/Linux
-~~~~~~~~~
-Compilieren:  gcc -Wall -O cube-3c.c opengl-magic-double.c \
-              -lGL -lGLU -lglut -o cube-3c
-Aufrufen:     ./cube-3c
-
-MacOS
-~~~~~
-Compilieren:  gcc -Wall -O cube-3c.c opengl-magic-double.c \
-              -framework OpenGL -framework GLUT -o cube-3c
-Aufrufen:     ./cube-3c
-
-Cygwin mit X11
-~~~~~~~~~~~~~~
-Compilieren:  gcc -Wall -O cube-3c.c opengl-magic-double.c \
-              -lGL -lGLU -lglut -o cube-3c
-Aufrufen:     DISPLAY=:0.0 ./cube-3c
-oder:
-  einmalig:   export DISPLAY=:0.0
-  danach:     ./cube-3c
-
-Vorher einmalig: X-Server starten
-              XWin -multiwindow &
-
-Cygwin ohne X11
-~~~~~~~~~~~~~~~
-Compilieren:  i686-pc-mingw32-gcc -I freeglut/include -L freeglut/lib \
-              -Wall -O cube-3c.c opengl-magic-double.c \
-              -lOpenGL32 -lGLU32 -lfreeglut -o cube-3c
-Aufrufen:     ./cube-3c
-
-MinGW ohne X11
-~~~~~~~~~~~~~~
-Compilieren:  gcc -I freeglut/include -L freeglut/lib \
-              -Wall -O cube-3c.c opengl-magic-double.c \
-              -lOpenGL32 -lGLU32 -lfreeglut -o cube-3c
-Aufrufen:     ./cube-3c

20171106/egal.txt

+../common/egal.txt
\ No newline at end of file

20171106/opengl-magic.c

-#if defined(__APPLE__) || defined(MACOSX)
-  #include <OpenGL/gl.h>
-  #include <OpenGL/glu.h>
-  #include <GLUT/glut.h>
-#else
-  #include <GL/gl.h>
-  #include <GL/glu.h>
-  #include <GL/glut.h>
-#endif
-
-#include "opengl-magic.h"
-
-void init_opengl (int *argcp, char **argv, char *window_name)
-{
-  glutInit (argcp, argv);
-  glutInitDisplayMode (GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH);
-  glutInitWindowSize (1024, 768);
-  glutCreateWindow (window_name);
-  glMatrixMode (GL_PROJECTION);
-  glLoadIdentity ();
-  gluPerspective (20.0, -1.33333, 3.0, 7.0);
-  glMatrixMode (GL_MODELVIEW);
-  glLoadIdentity ();
-  glTranslatef (0.0, 0.0, -5.0);
-  glClearColor (0.0, 0.0, 0.0, 0.0);
-  glEnable (GL_DEPTH_TEST);
-  glEnable (GL_LIGHTING);
-  glEnable (GL_LIGHT0);
-  static GLfloat light0_position[] = { 1.0, 0.0, 1.0, 0.0 };
-  glLightfv (GL_LIGHT0, GL_POSITION, light0_position);
-}
-
-void set_material_color (float r, float g, float b)
-{
-  GLfloat color[] = { r, g, b };
-  glMaterialfv (GL_FRONT, GL_AMBIENT, color);
-  glMaterialfv (GL_FRONT, GL_DIFFUSE, color);
-}
-
-#if defined(__APPLE__) || defined(MACOSX)
-
-void glutSolidCylinder (double radius, double height, int slices, int stacks)
-{
-  GLUquadricObj *q = gluNewQuadric ();
-  gluCylinder (q, radius, radius, height, slices, stacks);
-  gluDeleteQuadric (q);
-}
-
-#endif

20171106/opengl-magic.c

+../common/opengl-magic.c
\ No newline at end of file

20171106/opengl-magic.h

-#ifndef OPENGL_MAGIC_H
-#define OPENGL_MAGIC_H
-
-extern void init_opengl (int *argcp, char **argv, char *window_name);
-extern void set_material_color (float r, float g, float b);
-
-#ifdef __MACOSX__
-  extern void glutSolidCylinder (double radius, double height, int slices, int stacks);
-#endif
-
-#endif /* OPENGL_MAGIC_H */

20171106/opengl-magic.h

+../common/opengl-magic.h
\ No newline at end of file

20171108/earth-texture.png

+../common/earth-texture.png
\ No newline at end of file

20171108/egal.txt

+../common/egal.txt
\ No newline at end of file

20171108/moon-texture.png

+../common/moon-texture.png
\ No newline at end of file

20171108/opengl-magic.c

+../common/opengl-magic.c
\ No newline at end of file

20171108/opengl-magic.h

+../common/opengl-magic.h
\ No newline at end of file

20171108/orbit-1.c

+#include <GL/gl.h>
+#include <GL/glu.h>
+#include <GL/glut.h>
+#include "opengl-magic.h"
+#include "textured-spheres.h"
+
+float t = 0.0;
+GLuint earth_texture, moon_texture;
+
+void draw_earth (void)
+{
+  glPushMatrix ();
+  glRotatef (90, 1.0, 0.0, 0.0);
+  glRotatef (100.0 * t, 0.0, 0.0, 1.0);
+  draw_textured_sphere (earth_texture, 0.25512, 63, 20);
+  glPopMatrix ();
+}
+
+void draw_moon (void)
+{
+  glPushMatrix ();
+  glRotatef (90, 1.0, 0.0, 0.0);
+  glRotatef (-90, 0.0, 0.0, 1.0);
+  draw_textured_sphere (moon_texture, 0.06952, 31, 10);
+  glPopMatrix ();
+}
+
+void draw (void)
+{
+  glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+  glPushMatrix ();
+  glRotatef (23.44, 1.0, 0.0, -1.0);
+  draw_earth ();
+  glRotatef (5.145, 0.0, 1.0, 1.0);
+  glRotatef (30.0 * t, 0.0, -1.0, 0.0);
+  glTranslatef (0.9, 0.0, 0.0);
+  draw_moon ();
+  glPopMatrix ();
+  glFlush ();
+  glutSwapBuffers ();
+}
+
+void timer_handler (int value)
+{
+  t += 0.05;
+  glutPostRedisplay ();
+  glutTimerFunc (50, timer_handler, 0);
+}
+
+int main (int argc, char **argv)
+{
+  init_opengl (&argc, argv, "Orbit");
+  init_texture ("earth-texture.png", &earth_texture);
+  init_texture ("moon-texture.png", &moon_texture);
+  glutDisplayFunc (draw);
+  glutTimerFunc (50, timer_handler, 0);
+  glutMainLoop ();
+  return 0;
+}

20171108/pendulum-1.c

+#include <GL/gl.h>
+#include <GL/glu.h>
+#include <GL/freeglut.h>
+#include <math.h>
+#include "opengl-magic.h"
+
+#define phi0 1.0    /* geg. Anfangswert */
+#define omega0 0.0  /* geg. Anfangswert */
+#define dt 0.05
+#define g 9.81
+#define l 1.0
+
+double t = 0.0;
+double phi = phi0;
+double omega = omega0;
+
+void draw (void)
+{
+  glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+  set_material_color (0.8, 0.8, 1.0);
+  glPushMatrix ();
+  glRotatef (90, 1.0, 0.0, 0.0);
+  glTranslatef (0.0, 0.0, -0.75);
+  glRotatef (180.0 + phi / M_PI * 180.0, 0.0, 1.0, 0.0);
+  glTranslatef (0.0, 0.0, -1.0);
+  glutSolidCylinder (0.01, l, 13, 1);
+  glutSolidSphere (0.1, 31, 10);
+  glPopMatrix ();
+  glFlush ();
+  glutSwapBuffers ();
+}
+
+void timer_handler (int value)
+{
+  t += dt;
+  glutPostRedisplay ();
+  glutTimerFunc (50, timer_handler, 0);
+}
+
+int main (int argc, char **argv)
+{
+  init_opengl (&argc, argv, "Pendulum");
+  glutDisplayFunc (draw);
+  glutTimerFunc (50, timer_handler, 0);
+  glutMainLoop ();
+  return 0;
+}

20171108/pendulum-2.c

+#include <GL/gl.h>
+#include <GL/glu.h>
+#include <GL/freeglut.h>
+#include <math.h>
+#include "opengl-magic.h"
+
+#define phi0 1.0    /* geg. Anfangswert */
+#define omega0 0.0  /* geg. Anfangswert */
+#define dt 0.05
+#define g 9.81
+#define l 1.0
+
+double t = 0.0;
+double phi = phi0;
+double omega = omega0;
+
+void draw (void)
+{
+  glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+  set_material_color (0.8, 0.8, 1.0);
+  glPushMatrix ();
+  glRotatef (90, 1.0, 0.0, 0.0);
+  glTranslatef (0.0, 0.0, -0.75);
+  glRotatef (180.0 + phi / M_PI * 180.0, 0.0, 1.0, 0.0);
+  glTranslatef (0.0, 0.0, -1.0);
+  glutSolidCylinder (0.01, l, 13, 1);
+  glutSolidSphere (0.1, 31, 10);
+  glPopMatrix ();
+  glFlush ();
+  glutSwapBuffers ();
+}
+
+void timer_handler (int value)
+{
+  t += dt;
+  phi += dt * omega;
+  omega += dt * (-g / l) * sin (phi);
+  glutPostRedisplay ();
+  glutTimerFunc (50, timer_handler, 0);
+}
+
+int main (int argc, char **argv)
+{
+  init_opengl (&argc, argv, "Pendulum");
+  glutDisplayFunc (draw);
+  glutTimerFunc (50, timer_handler, 0);
+  glutMainLoop ();
+  return 0;
+}

20171108/pendulum-3.c

+#include <GL/gl.h>
+#include <GL/glu.h>
+#include <GL/freeglut.h>
+#include <math.h>
+#include "opengl-magic.h"
+
+#define phi0 1.0    /* geg. Anfangswert */
+#define omega0 0.0  /* geg. Anfangswert */
+#define dt 0.05
+#define g 9.81
+#define l 1.0
+
+double t = 0.0;
+double phi = phi0;
+double omega = omega0;
+
+void draw (void)
+{
+  glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+  set_material_color (1.0, 1.0, 0.8);
+  glPushMatrix ();
+  glRotatef (90, 1.0, 0.0, 0.0);
+  glTranslatef (0.0, 0.0, -0.75);
+  glRotatef (180.0 + phi / M_PI * 180.0, 0.0, 1.0, 0.0);
+  glTranslatef (0.0, 0.0, -1.0);
+  glutSolidCylinder (0.01, l, 13, 1);
+  glutSolidSphere (0.1, 31, 10);
+  glPopMatrix ();
+  glFlush ();
+  glutSwapBuffers ();
+}
+
+void timer_handler (int value)
+{
+  t += dt;
+  phi += dt * omega;
+  omega += dt * (-g / l) * phi;
+  glutPostRedisplay ();
+  glutTimerFunc (50, timer_handler, 0);
+}
+
+int main (int argc, char **argv)
+{
+  init_opengl (&argc, argv, "Pendulum");
+  glutDisplayFunc (draw);
+  glutTimerFunc (50, timer_handler, 0);
+  glutMainLoop ();
+  return 0;
+}

20171108/pendulum-4.c

+#include <GL/gl.h>
+#include <GL/glu.h>
+#include <GL/freeglut.h>
+#include <math.h>
+#include "opengl-magic.h"
+
+#define phi0 0.5    /* geg. Anfangswert */
+#define omega0 0.0  /* geg. Anfangswert */
+#define dt 0.05
+#define g 9.81
+#define l 1.0
+
+double t = 0.0;
+double phi_with_sin = phi0;
+double omega_with_sin= omega0;
+double phi_without_sin = phi0;
+double omega_without_sin= omega0;
+
+void draw_pendulum (double phi)
+{
+  glPushMatrix ();
+  glRotatef (90, 1.0, 0.0, 0.0);
+  glTranslatef (0.0, 0.0, -0.75);
+  glRotatef (180.0 + phi / M_PI * 180.0, 0.0, 1.0, 0.0);
+  glTranslatef (0.0, 0.0, -1.0);
+  glutSolidCylinder (0.01, 1.0, 13, 1);
+  glutSolidSphere (0.1, 31, 10);
+  glPopMatrix ();
+  glutSwapBuffers ();
+}
+
+void draw (void)
+{
+  glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+  set_material_color (0.8, 0.8, 1.0);
+  draw_pendulum (phi_with_sin);
+  set_material_color (1.0, 0.8, 0.8);
+  draw_pendulum (phi_without_sin);
+  set_material_color (0.8, 1.0, 0.8);
+  double A = phi0;
+  double B = 0.5 * M_PI;  /* 90° */
+  double phi_analytic = A * sin (sqrt (g / l) * t + B);
+  draw_pendulum (phi_analytic);
+  glFlush ();
+}
+
+void timer_handler (int value)
+{
+  t += dt;
+  phi_with_sin += dt * omega_with_sin;                   /* geg. Differentialgleichung */
+  omega_with_sin += - dt * g / l * sin (phi_with_sin);   /* geg. Differentialgleichung */
+                                                         /* _ohne_ Kleinwinkelnäherung */
+  phi_without_sin += dt * omega_without_sin;             /* geg. Differentialgleichung */
+  omega_without_sin += - dt * g / l * phi_without_sin;   /* geg. Differentialgleichung */
+                                                         /* _mit_ Kleinwinkelnäherung  */
+  glutPostRedisplay ();
+  glutTimerFunc (50, timer_handler, 0);
+}
+
+int main (int argc, char **argv)
+{
+  init_opengl (&argc, argv, "Pendulum");
+  glutDisplayFunc (draw);
+  glutTimerFunc (50, timer_handler, 0);
+  glutPostRedisplay ();
+  glutMainLoop ();
+  return 0;
+}

20171108/textured-spheres.c

+../common/textured-spheres.c
\ No newline at end of file

20171108/textured-spheres.h

+../common/textured-spheres.h
\ No newline at end of file

common/egal.txt

+GNU/Linux
+~~~~~~~~~
+Compilieren:  gcc -Wall -O cube-3c.c opengl-magic-double.c \
+              -lGL -lGLU -lglut -o cube-3c
+Aufrufen:     ./cube-3c
+
+MacOS
+~~~~~
+Compilieren:  gcc -Wall -O cube-3c.c opengl-magic-double.c \
+              -framework OpenGL -framework GLUT -o cube-3c
+Aufrufen:     ./cube-3c
+
+Cygwin mit X11
+~~~~~~~~~~~~~~
+Compilieren:  gcc -Wall -O cube-3c.c opengl-magic-double.c \
+              -lGL -lGLU -lglut -o cube-3c
+Aufrufen:     DISPLAY=:0.0 ./cube-3c
+oder:
+  einmalig:   export DISPLAY=:0.0
+  danach:     ./cube-3c
+
+Vorher einmalig: X-Server starten
+              XWin -multiwindow &
+
+Cygwin ohne X11
+~~~~~~~~~~~~~~~
+Compilieren:  i686-pc-mingw32-gcc -I freeglut/include -L freeglut/lib \
+              -Wall -O cube-3c.c opengl-magic-double.c \
+              -lOpenGL32 -lGLU32 -lfreeglut -o cube-3c
+Aufrufen:     ./cube-3c
+
+MinGW ohne X11
+~~~~~~~~~~~~~~
+Compilieren:  gcc -I freeglut/include -L freeglut/lib \
+              -Wall -O cube-3c.c opengl-magic-double.c \
+              -lOpenGL32 -lGLU32 -lfreeglut -o cube-3c
+Aufrufen:     ./cube-3c

common/opengl-magic.c

+#if defined(__APPLE__) || defined(MACOSX)
+  #include <OpenGL/gl.h>
+  #include <OpenGL/glu.h>
+  #include <GLUT/glut.h>
+#else
+  #include <GL/gl.h>
+  #include <GL/glu.h>
+  #include <GL/glut.h>
+#endif
+
+#include "opengl-magic.h"
+
+void init_opengl (int *argcp, char **argv, char *window_name)
+{
+  glutInit (argcp, argv);
+  glutInitDisplayMode (GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH);
+  glutInitWindowSize (1024, 768);
+  glutCreateWindow (window_name);
+  glMatrixMode (GL_PROJECTION);
+  glLoadIdentity ();
+  gluPerspective (20.0, -1.33333, 3.0, 7.0);
+  glMatrixMode (GL_MODELVIEW);
+  glLoadIdentity ();
+  glTranslatef (0.0, 0.0, -5.0);
+  glClearColor (0.0, 0.0, 0.0, 0.0);
+  glEnable (GL_DEPTH_TEST);
+  glEnable (GL_LIGHTING);
+  glEnable (GL_LIGHT0);
+  static GLfloat light0_position[] = { 1.0, 0.0, 1.0, 0.0 };
+  glLightfv (GL_LIGHT0, GL_POSITION, light0_position);
+}
+
+void set_material_color (float r, float g, float b)
+{
+  GLfloat color[] = { r, g, b };
+  glMaterialfv (GL_FRONT, GL_AMBIENT, color);
+  glMaterialfv (GL_FRONT, GL_DIFFUSE, color);
+}
+
+#if defined(__APPLE__) || defined(MACOSX)
+
+void glutSolidCylinder (double radius, double height, int slices, int stacks)
+{
+  GLUquadricObj *q = gluNewQuadric ();
+  gluCylinder (q, radius, radius, height, slices, stacks);
+  gluDeleteQuadric (q);
+}
+
+#endif