updated

git-svn-id: svn://anubis/misc/hilbert@15 bd8a9e45-a331-0410-811e-c64571078777

hilbert.c

@@ -6,26 +6,36 @@
 #include <SDL/SDL.h>
 #include <GL/gl.h>
 #include <GL/glu.h>
+#include <math.h>
 
 /* constants */
 #define SEGMENTS 16
 #define WIDTH	 800
 #define HEIGHT	 600
 
+/* macros */
+#define keepingMatrix(x) { glPushMatrix(); x; glPopMatrix(); }
+
 /* functions */
 void usage(void);
 void initgl(void);
 void display(void);
 void mainloop(void);
-void drawHilbert();
+void initLists(void);
+void tlRtDrwCyl(float x, float y, float z, float a, float u, float v, float w);
+void drawHilbert(int level, float size, int cap1, int cap2);
+void drawHilbert1(int cap1, int cap2);
 
 /* global variables */
-int level = 2;
+int level = 1;
 float size = 0.4;
 SDL_Surface * sdlScreen;
 int winWidth = WIDTH;
 int winHeight = HEIGHT;
-int displayList = -1;
+int hilbertList = -1;
+int sphereList = -1;
+int cylList = -1;
+const float diffuse[4] = {0.9f, 0.6f, 0.1f, 1.0f};
 
 int	main(int argc, char *argv[])
 {
@@ -68,6 +78,7 @@ int	main(int argc, char *argv[])
 	SDL_WM_SetCaption(argv[0], argv[0]);
 
 	initgl();
+	initLists();
 	mainloop();
 
 	return 0;
@@ -102,42 +113,125 @@ void initgl(void)
 {
 	glClearColor (0.0, 0.0, 0.0, 0.0);
 	glEnable(GL_DEPTH_TEST);
+	glEnable(GL_CULL_FACE);
+	glEnable(GL_LIGHTING);
+	glEnable(GL_LIGHT0);
 	glShadeModel(GL_SMOOTH);
 	glViewport(0, 0, winWidth, winHeight);
 	glMatrixMode(GL_PROJECTION);
 	glLoadIdentity();
-	gluPerspective(60.0, (GLfloat)winHeight/(GLfloat)winWidth, 1.0, 30.0);
+	gluPerspective(60.0, 1, 0.01, 3000.0);
 	glMatrixMode(GL_MODELVIEW);
 	glLoadIdentity();
-	glTranslatef(0.0, 0.0, -3.6);
+	gluLookAt(10, -10, 10,
+	          0, 0, 0,
+	          0, 0, 1);
+
+	/* set up materials */
+	glMaterialfv(GL_FRONT, GL_AMBIENT_AND_DIFFUSE, diffuse);
 }
 
 void display(void)
 {
 	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-
+	glCallList(hilbertList);
-	if (displayList >= 0)
-	{
-		glCallList(displayList);
-	}
-	else
-	{
-		displayList = glGenLists(1);
-		if (displayList < 0)
-		{
-			fprintf(stderr, "Error allocating display list!\n");
-			exit(132);
-		}
-		glNewList(displayList, GL_COMPILE_AND_EXECUTE);
-		drawHilbert();
-		glEndList();
-	}
-
 	SDL_GL_SwapBuffers();
 }
 
-void drawHilbert()
+void drawHilbert(int level, float size, int cap1, int cap2)
 {
+	if (level == 1)
+	{
+		drawHilbert1(cap1, cap2);
+	}
+}
+
+void drawHilbert1(int cap1, int cap2)
+{
+	if (cap1)
+	{
+		keepingMatrix(
+			glTranslatef(-0.5f, -0.5f, -0.5f);
+			glCallList(sphereList);
+		)
+	}
+	else
+	{
+		tlRtDrwCyl(-0.5, -1.0, -0.5, 90, 1.0, 0.0, 0.0);
+		tlRtDrwCyl(-0.5, -0.5, -0.5, 90, 1.0, 0.0, 0.0);
+	}
+
+	if (cap2)
+	{
+		keepingMatrix(
+			glTranslatef(0.5f, 0.5f, 0.5f);
+			glCallList(sphereList);
+		)
+	}
+	else
+	{
+		tlRtDrwCyl(-0.5, -1.0, 0.5, 90, 1.0, 0.0, 0.0);
+		tlRtDrwCyl(-0.5, -0.5, 0.5, 90, 1.0, 0.0, 0.0);
+	}
+
+	glColor3f(0.2, 0.2, 1.0);
+	glDisable(GL_LIGHTING);
+	glBegin(GL_LINE_STRIP);
+		glVertex3f(-0.5, -0.5, -0.5);
+		glVertex3f(-0.5, 0.5, -0.5);
+		glVertex3f(0.5, 0.5, -0.5);
+		glVertex3f(0.5, -0.5, -0.5);
+		glVertex3f(0.5, -0.5, 0.5);
+		glVertex3f(0.5, 0.5, 0.5);
+		glVertex3f(-0.5, 0.5, 0.5);
+		glVertex3f(-0.5, -0.5, 0.5);
+	glEnd();
+	glEnable(GL_LIGHTING);
+}
+
+void tlRtDrwCyl(float x, float y, float z, float a, float u, float v, float w)
+{
+	keepingMatrix(
+		glTranslatef(x, y, z);
+		glRotatef(a, u, v, w);
+		glCallList(cylList);
+	)
+}
+
+void initLists(void)
+{
+	GLUquadric * q;
+
+	hilbertList = glGenLists(1);
+	sphereList = glGenLists(1);
+	cylList = glGenLists(1);
+
+	if (hilbertList < 0 || sphereList < 0 || cylList < 0)
+	{
+		fprintf(stderr, "Error allocating display list!\n");
+		exit(132);
+	}
+
+	/* get a quadric object to draw with */
+	q = gluNewQuadric();
+
+	/* draw a sphere */
+	glNewList(sphereList, GL_COMPILE);
+		gluSphere(q, size, SEGMENTS, SEGMENTS/2);
+	glEndList();
+
+	/* draw a cylinder */
+	glNewList(cylList, GL_COMPILE);
+		gluCylinder(q, size, size, 0.25, SEGMENTS, SEGMENTS/4);
+	glEndList();
+
+	/* draw Hilbert curve */
+	glNewList(hilbertList, GL_COMPILE);
+		drawHilbert(level, size, 1, 1);
+	glEndList();
+
+	/* free quadric memory */
+	gluDeleteQuadric(q);
 }
 
 void usage(void)