diff options
| -rw-r--r-- | progs/demos/tessdemo.c | 592 |
1 files changed, 343 insertions, 249 deletions
diff --git a/progs/demos/tessdemo.c b/progs/demos/tessdemo.c index 2e02b9027e..3648ebd084 100644 --- a/progs/demos/tessdemo.c +++ b/progs/demos/tessdemo.c @@ -1,331 +1,410 @@ -/* $Id: tessdemo.c,v 1.8 2000/07/11 14:11:58 brianp Exp $ */ +/* $Id: tessdemo.c,v 1.9 2001/03/21 02:43:14 gareth Exp $ */ /* * A demo of the GLU polygon tesselation functions written by Bogdan Sikorski. + * Updated for GLU 1.3 tessellation by Gareth Hughes <gareth@valinux.com> */ - #include <GL/glut.h> #include <stdio.h> #include <stdlib.h> #include <string.h> -#define MAX_POINTS 200 -#define MAX_CONTOURS 50 +#define MAX_POINTS 256 +#define MAX_CONTOURS 32 +#define MAX_TRIANGLES 256 -static int menu; -typedef enum -{ QUIT, TESSELATE, CLEAR } -menu_entries; +#ifndef GLCALLBACK +#ifdef CALLBACK +#define GLCALLBACK CALLBACK +#else +#define GLCALLBACK +#endif +#endif -typedef enum -{ DEFINE, TESSELATED } -mode_type; +#ifdef GLU_VERSION_1_2 -struct -{ - GLint p[MAX_POINTS][2]; - GLuint point_cnt; -} -contours[MAX_CONTOURS]; +typedef enum{ QUIT, TESSELATE, CLEAR } menu_entries; +typedef enum{ DEFINE, TESSELATED } mode_type; -static GLuint contour_cnt; -static GLsizei width, height; -static mode_type mode; +static GLsizei width, height; +static GLuint contour_cnt; +static GLuint triangle_cnt; -struct -{ - GLsizei no; - GLfloat color[3]; - GLint p[3][2]; - GLclampf p_color[3][3]; -} -triangle; +static mode_type mode; +static int menu; +static GLuint list_start; -static void GLCALLBACK -my_error(GLenum err) -{ - int len, i; - char const *str; - - glColor3f(0.9, 0.9, 0.9); - glRasterPos2i(5, 5); - str = (const char *) gluErrorString(err); - len = strlen(str); - for (i = 0; i < len; i++) - glutBitmapCharacter(GLUT_BITMAP_9_BY_15, str[i]); -} +static GLfloat edge_color[3]; +static struct { + GLfloat p[MAX_POINTS][2]; + GLuint point_cnt; +} contours[MAX_CONTOURS]; -static void GLCALLBACK -begin_callback(GLenum mode) +static struct { + GLsizei no; + GLfloat p[3][2]; + GLclampf color[3][3]; +} triangles[MAX_TRIANGLES]; + + + +static void GLCALLBACK error_callback( GLenum err ) { - triangle.no = 0; + int len, i; + char const *str; + + glColor3f( 0.9, 0.9, 0.9 ); + glRasterPos2i( 5, 5 ); + + str = (const char *) gluErrorString( err ); + len = strlen( str ); + + for ( i = 0 ; i < len ; i++ ) { + glutBitmapCharacter( GLUT_BITMAP_9_BY_15, str[i] ); + } } +static void GLCALLBACK begin_callback( GLenum mode ) +{ + /* Allow multiple triangles to be output inside the begin/end pair. */ + triangle_cnt = 0; + triangles[triangle_cnt].no = 0; +} -static void GLCALLBACK -edge_callback(GLenum flag) +static void GLCALLBACK edge_callback( GLenum flag ) { - if (flag == GL_TRUE) { - triangle.color[0] = 1.0; - triangle.color[1] = 1.0; - triangle.color[2] = 0.5; - } - else { - triangle.color[0] = 1.0; - triangle.color[1] = 0.0; - triangle.color[2] = 0.0; + /* Persist the edge flag across triangles. */ + if ( flag == GL_TRUE ) { + edge_color[0] = 1.0; + edge_color[1] = 1.0; + edge_color[2] = 0.5; + } else { + edge_color[0] = 1.0; + edge_color[1] = 0.0; + edge_color[2] = 0.0; } } - -static void GLCALLBACK -end_callback() +static void GLCALLBACK end_callback() { - glBegin(GL_LINES); - glColor3f(triangle.p_color[0][0], triangle.p_color[0][1], - triangle.p_color[0][2]); - glVertex2i(triangle.p[0][0], triangle.p[0][1]); - glVertex2i(triangle.p[1][0], triangle.p[1][1]); - glColor3f(triangle.p_color[1][0], triangle.p_color[1][1], - triangle.p_color[1][2]); - glVertex2i(triangle.p[1][0], triangle.p[1][1]); - glVertex2i(triangle.p[2][0], triangle.p[2][1]); - glColor3f(triangle.p_color[2][0], triangle.p_color[2][1], - triangle.p_color[2][2]); - glVertex2i(triangle.p[2][0], triangle.p[2][1]); - glVertex2i(triangle.p[0][0], triangle.p[0][1]); + GLint i; + + glBegin( GL_LINES ); + + /* Output the three edges of each triangle as lines colored + according to their edge flag. */ + for ( i = 0 ; i < triangle_cnt ; i++ ) { + glColor3f( triangles[i].color[0][0], + triangles[i].color[0][1], + triangles[i].color[0][2] ); + + glVertex2f( triangles[i].p[0][0], triangles[i].p[0][1] ); + glVertex2f( triangles[i].p[1][0], triangles[i].p[1][1] ); + + glColor3f( triangles[i].color[1][0], + triangles[i].color[1][1], + triangles[i].color[1][2] ); + + glVertex2f( triangles[i].p[1][0], triangles[i].p[1][1] ); + glVertex2f( triangles[i].p[2][0], triangles[i].p[2][1] ); + + glColor3f( triangles[i].color[2][0], + triangles[i].color[2][1], + triangles[i].color[2][2] ); + + glVertex2f( triangles[i].p[2][0], triangles[i].p[2][1] ); + glVertex2f( triangles[i].p[0][0], triangles[i].p[0][1] ); + } + glEnd(); } +static void GLCALLBACK vertex_callback( void *data ) +{ + GLsizei no; + GLfloat *p; + + p = (GLfloat *) data; + no = triangles[triangle_cnt].no; + + triangles[triangle_cnt].p[no][0] = p[0]; + triangles[triangle_cnt].p[no][1] = p[1]; + + triangles[triangle_cnt].color[no][0] = edge_color[0]; + triangles[triangle_cnt].color[no][1] = edge_color[1]; + triangles[triangle_cnt].color[no][2] = edge_color[2]; -static void GLCALLBACK -vertex_callback(void *data) + /* After every three vertices, initialize the next triangle. */ + if ( ++(triangles[triangle_cnt].no) == 3 ) { + triangle_cnt++; + triangles[triangle_cnt].no = 0; + } +} + +static void GLCALLBACK combine_callback( GLdouble coords[3], + GLdouble *vertex_data[4], + GLfloat weight[4], void **data ) { - GLsizei no; - GLint *p; - - p = (GLint *) data; - no = triangle.no; - triangle.p[no][0] = p[0]; - triangle.p[no][1] = p[1]; - triangle.p_color[no][0] = triangle.color[0]; - triangle.p_color[no][1] = triangle.color[1]; - triangle.p_color[no][2] = triangle.color[2]; - ++(triangle.no); + GLfloat *vertex; + + vertex = (GLfloat *) malloc( 2 * sizeof(GLfloat) ); + + vertex[0] = (GLfloat) coords[0]; + vertex[1] = (GLfloat) coords[1]; + + *data = vertex; } -static void -set_screen_wh(GLsizei w, GLsizei h) +static void set_screen_wh( GLsizei w, GLsizei h ) { width = w; height = h; } - -static void -tesse(void) +static void tesse( void ) { - GLUtriangulatorObj *tobj; - GLdouble data[3]; - GLuint i, j, point_cnt; + GLUtesselator *tobj; + GLdouble data[3]; + GLuint i, j, point_cnt; + + list_start = glGenLists( 2 ); tobj = gluNewTess(); - if (tobj != NULL) { - glClear(GL_COLOR_BUFFER_BIT); - glColor3f(0.7, 0.7, 0.0); - gluTessCallback(tobj, GLU_BEGIN, glBegin); - gluTessCallback(tobj, GLU_END, glEnd); - gluTessCallback(tobj, GLU_ERROR, my_error); - gluTessCallback(tobj, GLU_VERTEX, glVertex2iv); - gluBeginPolygon(tobj); - for (j = 0; j <= contour_cnt; j++) { + + if ( tobj != NULL ) { + gluTessNormal( tobj, 0.0, 0.0, 1.0 ); + gluTessCallback( tobj, GLU_TESS_BEGIN, glBegin ); + gluTessCallback( tobj, GLU_TESS_VERTEX, glVertex2fv ); + gluTessCallback( tobj, GLU_TESS_END, glEnd ); + gluTessCallback( tobj, GLU_TESS_ERROR, error_callback ); + gluTessCallback( tobj, GLU_TESS_COMBINE, combine_callback ); + + glNewList( list_start, GL_COMPILE ); + gluBeginPolygon( tobj ); + + for ( j = 0 ; j <= contour_cnt ; j++ ) { point_cnt = contours[j].point_cnt; - gluNextContour(tobj, GLU_UNKNOWN); - for (i = 0; i < point_cnt; i++) { - data[0] = (GLdouble) (contours[j].p[i][0]); - data[1] = (GLdouble) (contours[j].p[i][1]); + gluNextContour( tobj, GLU_UNKNOWN ); + + for ( i = 0 ; i < point_cnt ; i++ ) { + data[0] = (GLdouble)( contours[j].p[i][0] ); + data[1] = (GLdouble)( contours[j].p[i][1] ); data[2] = 0.0; - gluTessVertex(tobj, data, contours[j].p[i]); + gluTessVertex( tobj, data, contours[j].p[i] ); } } - gluEndPolygon(tobj); - glLineWidth(2.0); - gluTessCallback(tobj, GLU_BEGIN, begin_callback); - gluTessCallback(tobj, GLU_END, end_callback); - gluTessCallback(tobj, GLU_VERTEX, vertex_callback); - gluTessCallback(tobj, GLU_EDGE_FLAG, edge_callback); - gluBeginPolygon(tobj); - for (j = 0; j <= contour_cnt; j++) { + + gluEndPolygon( tobj ); + glEndList(); + + gluTessCallback( tobj, GLU_TESS_BEGIN, begin_callback ); + gluTessCallback( tobj, GLU_TESS_VERTEX, vertex_callback ); + gluTessCallback( tobj, GLU_TESS_END, end_callback ); + gluTessCallback( tobj, GLU_TESS_EDGE_FLAG, edge_callback ); + + glNewList( list_start + 1, GL_COMPILE ); + gluBeginPolygon( tobj ); + + for ( j = 0 ; j <= contour_cnt ; j++ ) { point_cnt = contours[j].point_cnt; - gluNextContour(tobj, GLU_UNKNOWN); - for (i = 0; i < point_cnt; i++) { - data[0] = (GLdouble) (contours[j].p[i][0]); - data[1] = (GLdouble) (contours[j].p[i][1]); + gluNextContour( tobj, GLU_UNKNOWN ); + + for ( i = 0 ; i < point_cnt ; i++ ) { + data[0] = (GLdouble)( contours[j].p[i][0] ); + data[1] = (GLdouble)( contours[j].p[i][1] ); data[2] = 0.0; - gluTessVertex(tobj, data, contours[j].p[i]); + gluTessVertex( tobj, data, contours[j].p[i] ); } } - gluEndPolygon(tobj); - gluDeleteTess(tobj); - glutMouseFunc(NULL); - glColor3f(1.0, 1.0, 0.0); - glLineWidth(1.0); + + gluEndPolygon( tobj ); + glEndList(); + + gluDeleteTess( tobj ); + + glutMouseFunc( NULL ); mode = TESSELATED; } } - -static void -left_down(int x1, int y1) +static void left_down( int x1, int y1 ) { - GLint P[2]; - GLuint point_cnt; + GLfloat P[2]; + GLuint point_cnt; /* translate GLUT into GL coordinates */ + P[0] = x1; P[1] = height - y1; + point_cnt = contours[contour_cnt].point_cnt; + contours[contour_cnt].p[point_cnt][0] = P[0]; contours[contour_cnt].p[point_cnt][1] = P[1]; - glBegin(GL_LINES); - if (point_cnt) { - glVertex2iv(contours[contour_cnt].p[point_cnt - 1]); - glVertex2iv(P); - } - else { - glVertex2iv(P); - glVertex2iv(P); + + glBegin( GL_LINES ); + + if ( point_cnt ) { + glVertex2fv( contours[contour_cnt].p[point_cnt-1] ); + glVertex2fv( P ); + } else { + glVertex2fv( P ); + glVertex2fv( P ); } + glEnd(); glFinish(); - ++(contours[contour_cnt].point_cnt); -} + contours[contour_cnt].point_cnt++; +} -static void -middle_down(int x1, int y1) +static void middle_down( int x1, int y1 ) { - GLuint point_cnt; + GLuint point_cnt; + (void) x1; + (void) y1; point_cnt = contours[contour_cnt].point_cnt; - if (point_cnt > 2) { - glBegin(GL_LINES); - glVertex2iv(contours[contour_cnt].p[0]); - glVertex2iv(contours[contour_cnt].p[point_cnt - 1]); + + if ( point_cnt > 2 ) { + glBegin( GL_LINES ); + + glVertex2fv( contours[contour_cnt].p[0] ); + glVertex2fv( contours[contour_cnt].p[point_cnt-1] ); + contours[contour_cnt].p[point_cnt][0] = -1; + glEnd(); glFinish(); + contour_cnt++; contours[contour_cnt].point_cnt = 0; } } - -static void -mouse_clicked(int button, int state, int x, int y) +static void mouse_clicked( int button, int state, int x, int y ) { - x -= x % 10; - y -= y % 10; - switch (button) { + x -= x%10; + y -= y%10; + + switch ( button ) { case GLUT_LEFT_BUTTON: - if (state == GLUT_DOWN) - left_down(x, y); + if ( state == GLUT_DOWN ) { + left_down( x, y ); + } break; case GLUT_MIDDLE_BUTTON: - if (state == GLUT_DOWN) - middle_down(x, y); + if ( state == GLUT_DOWN ) { + middle_down( x, y ); + } break; } } - -static void -display(void) +static void display( void ) { - GLuint i, j; + GLuint i,j; GLuint point_cnt; - glClear(GL_COLOR_BUFFER_BIT); - switch (mode) { + glClear( GL_COLOR_BUFFER_BIT ); + + switch ( mode ) { case DEFINE: /* draw grid */ - glColor3f(0.6, 0.5, 0.5); - glBegin(GL_LINES); - for (i = 0; i < width; i += 10) - for (j = 0; j < height; j += 10) { - glVertex2i(0, j); - glVertex2i(width, j); - glVertex2i(i, height); - glVertex2i(i, 0); + glColor3f( 0.6, 0.5, 0.5 ); + + glBegin( GL_LINES ); + + for ( i = 0 ; i < width ; i += 10 ) { + for ( j = 0 ; j < height ; j += 10 ) { + glVertex2i( 0, j ); + glVertex2i( width, j ); + glVertex2i( i, height ); + glVertex2i( i, 0 ); } + } + glEnd(); - glColor3f(1.0, 1.0, 0.0); - for (i = 0; i <= contour_cnt; i++) { + + glColor3f( 1.0, 1.0, 0.0 ); + + for ( i = 0 ; i <= contour_cnt ; i++ ) { point_cnt = contours[i].point_cnt; - glBegin(GL_LINES); - switch (point_cnt) { + + glBegin( GL_LINES ); + + switch ( point_cnt ) { case 0: break; case 1: - glVertex2iv(contours[i].p[0]); - glVertex2iv(contours[i].p[0]); + glVertex2fv( contours[i].p[0] ); + glVertex2fv( contours[i].p[0] ); break; case 2: - glVertex2iv(contours[i].p[0]); - glVertex2iv(contours[i].p[1]); + glVertex2fv( contours[i].p[0] ); + glVertex2fv( contours[i].p[1] ); break; default: --point_cnt; - for (j = 0; j < point_cnt; j++) { - glVertex2iv(contours[i].p[j]); - glVertex2iv(contours[i].p[j + 1]); + for ( j = 0 ; j < point_cnt ; j++ ) { + glVertex2fv( contours[i].p[j] ); + glVertex2fv( contours[i].p[j+1] ); } - if (contours[i].p[j + 1][0] == -1) { - glVertex2iv(contours[i].p[0]); - glVertex2iv(contours[i].p[j]); + if ( contours[i].p[j+1][0] == -1 ) { + glVertex2fv( contours[i].p[0] ); + glVertex2fv( contours[i].p[j] ); } break; } + glEnd(); } + glFinish(); break; + case TESSELATED: - /* draw lines */ - tesse(); + /* draw triangles */ + glColor3f( 0.7, 0.7, 0.0 ); + glCallList( list_start ); + + glLineWidth( 2.0 ); + glCallList( list_start + 1 ); + glLineWidth( 1.0 ); + + glFlush(); break; } - glColor3f(1.0, 1.0, 0.0); + glColor3f( 1.0, 1.0, 0.0 ); } - -static void -clear(void) +static void clear( void ) { contour_cnt = 0; contours[0].point_cnt = 0; - glutMouseFunc(mouse_clicked); + triangle_cnt = 0; + + glutMouseFunc( mouse_clicked ); + mode = DEFINE; - display(); -} + glDeleteLists( list_start, 2 ); + list_start = 0; +} -static void -quit(void) +static void quit( void ) { - exit(0); + exit( 0 ); } - -static void -menu_selected(int entry) +static void menu_selected( int entry ) { - switch (entry) { + switch ( entry ) { case CLEAR: clear(); break; @@ -336,87 +415,102 @@ menu_selected(int entry) quit(); break; } -} + glutPostRedisplay(); +} -static void -key_pressed(unsigned char key, int x, int y) +static void key_pressed( unsigned char key, int x, int y ) { - switch (key) { + (void) x; + (void) y; + + switch ( key ) { + case 'c': + case 'C': + clear(); + break; case 't': case 'T': tesse(); - glFinish(); break; case 'q': case 'Q': quit(); break; - case 'c': - case 'C': - clear(); - break; } -} + glutPostRedisplay(); +} -static void -myinit(void) +static void myinit( void ) { -/* clear background to gray */ - glClearColor(0.4, 0.4, 0.4, 0.0); - glShadeModel(GL_FLAT); - - menu = glutCreateMenu(menu_selected); - glutAddMenuEntry("clear", CLEAR); - glutAddMenuEntry("tesselate", TESSELATE); - glutAddMenuEntry("quit", QUIT); - glutAttachMenu(GLUT_RIGHT_BUTTON); - glutMouseFunc(mouse_clicked); - glutKeyboardFunc(key_pressed); + /* clear background to gray */ + glClearColor( 0.4, 0.4, 0.4, 0.0 ); + glShadeModel( GL_FLAT ); + glPolygonMode( GL_FRONT, GL_FILL ); + + menu = glutCreateMenu( menu_selected ); + + glutAddMenuEntry( "clear", CLEAR ); + glutAddMenuEntry( "tesselate", TESSELATE ); + glutAddMenuEntry( "quit", QUIT ); + + glutAttachMenu( GLUT_RIGHT_BUTTON ); + + glutMouseFunc( mouse_clicked ); + glutKeyboardFunc( key_pressed ); + contour_cnt = 0; - glPolygonMode(GL_FRONT, GL_FILL); mode = DEFINE; } - -static void -reshape(GLsizei w, GLsizei h) +static void reshape( GLsizei w, GLsizei h ) { - glViewport(0, 0, w, h); - glMatrixMode(GL_PROJECTION); + glViewport( 0, 0, w, h ); + + glMatrixMode( GL_PROJECTION ); glLoadIdentity(); - glOrtho(0.0, (GLdouble) w, 0.0, (GLdouble) h, -1.0, 1.0); - glMatrixMode(GL_MODELVIEW); + glOrtho( 0.0, (GLdouble)w, 0.0, (GLdouble)h, -1.0, 1.0 ); + + glMatrixMode( GL_MODELVIEW ); glLoadIdentity(); - set_screen_wh(w, h); + + set_screen_wh( w, h ); } -static void -usage(void) +static void usage( void ) { - printf("Use left mouse button to place vertices.\n"); - printf("Press middle mouse button when done.\n"); - printf("Select tesselate from the pop-up menu.\n"); + printf( "Use left mouse button to place vertices.\n" ); + printf( "Press middle mouse button when done.\n" ); + printf( "Select tesselate from the pop-up menu.\n" ); } +#endif -/* Main Loop - * Open window with initial window size, title bar, - * RGBA display mode, and handle input events. - */ -int -main(int argc, char **argv) + +int main( int argc, char **argv ) { + const char *version = (const char *) gluGetString( GLU_VERSION ); + printf( "GLU version string: %s\n", version ); + if ( strstr( version, "1.0" ) || strstr( version, "1.1" ) ) { + fprintf( stderr, "Sorry, this demo reqiures GLU 1.2 or later.\n" ); + exit( 1 ); + } + usage(); - glutInit(&argc, argv); - glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); - glutInitWindowSize(400, 400); - glutCreateWindow(argv[0]); + + glutInit( &argc, argv ); + glutInitDisplayMode( GLUT_SINGLE | GLUT_RGB ); + glutInitWindowSize( 400, 400 ); + glutCreateWindow( argv[0] ); + myinit(); - glutDisplayFunc(display); - glutReshapeFunc(reshape); + + glutDisplayFunc( display ); + glutReshapeFunc( reshape ); + glutMainLoop(); + return 0; } |