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/*
* FILE:
* joinoffset.c
*
* FUNCTION:
* this demo demonstrates the various join styles
*
* HISTORY:
* Copyright (c) 1995 Linas Vepstas <linas@linas.org>
*/
/* required include files */
#include <GL/gl.h>
#include <GL/glut.h>
#include <GL/gle.h>
#include "main.h"
/* ------------------------------------------------------- */
/* the arrays in which we will store the polyline */
#define NPTS 100
double points [NPTS][3];
float colors [NPTS][3];
int idx = 0;
/* some utilities for filling that array */
#define PSCALE 0.5
#define PNT(x,y,z) { \
points[idx][0] = PSCALE * x; \
points[idx][1] = PSCALE * y; \
points[idx][2] = PSCALE * z; \
idx ++; \
}
#define COL(r,g,b) { \
colors[idx][0] = r; \
colors[idx][1] = g; \
colors[idx][2] = b; \
}
/* the arrays in which we will store the contour */
#define NCONTOUR 100
double contour_points [NCONTOUR][2];
int cidx = 0;
/* some utilities for filling that array */
#define C_PNT(x,y) { \
contour_points[cidx][0] = x; \
contour_points[cidx][1] = y; \
cidx ++; \
}
/* ------------------------------------------------------- */
/*
* Initialize a bent shape with three segments.
* The data format is a polyline.
*
* NOTE that neither the first, nor the last segment are drawn.
* The first & last segment serve only to determine that angle
* at which the endcaps are drawn.
*/
void InitStuff (void)
{
COL (0.0, 0.0, 0.0);
PNT (16.0, 0.0, 0.0);
COL (0.2, 0.8, 0.5);
PNT (0.0, -16.0, 0.0);
COL (0.0, 0.8, 0.3);
PNT (-16.0, 0.0, 0.0);
COL (0.8, 0.3, 0.0);
PNT (0.0, 16.0, 0.0);
COL (0.2, 0.3, 0.9);
PNT (16.0, 0.0, 0.0);
COL (0.2, 0.8, 0.5);
PNT (0.0, -16.0, 0.0);
COL (0.0, 0.0, 0.0);
PNT (-16.0, 0.0, 0.0);
C_PNT (-0.8, -0.5);
C_PNT (-1.8, 0.0);
C_PNT (-1.2, 0.3);
C_PNT (-0.7, 0.8);
C_PNT (-0.2, 1.3);
C_PNT (0.0, 1.6);
C_PNT (0.2, 1.3);
C_PNT (0.7, 0.8);
C_PNT (1.2, 0.3);
C_PNT (1.8, 0.0);
C_PNT (0.8, -0.5);
gleSetJoinStyle (TUBE_JN_ANGLE | TUBE_CONTOUR_CLOSED | TUBE_JN_CAP);
}
double up_vector[3] = {1.0, 0.0, 0.0};
/* ------------------------------------------------------- */
/* draw the extrusion */
void DrawStuff (void)
{
double moved_contour [NCONTOUR][2];
int style, save_style;
int i;
for (i=0; i<cidx; i++) {
moved_contour[i][0] = contour_points [i][0];
moved_contour[i][1] = contour_points [i][1] + 0.05 * (lasty-200.0);
}
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
/* set up some matrices so that the object spins with the mouse */
glPushMatrix ();
glTranslatef (0.0, 4.0, -80.0);
glRotatef (0.5*lastx, 0.0, 1.0, 0.0);
gleExtrusion (cidx, moved_contour, contour_points, up_vector,
idx, points, colors);
glPopMatrix ();
/* draw a seond copy, this time with the raw style, to compare
* things against */
glPushMatrix ();
glTranslatef (0.0, -4.0, -80.0);
glRotatef (0.5*lastx, 0.0, 1.0, 0.0);
save_style = gleGetJoinStyle ();
style = save_style;
style &= ~TUBE_JN_MASK;
style |= TUBE_JN_RAW;
gleSetJoinStyle (style);
gleExtrusion (cidx, moved_contour, contour_points, up_vector,
idx, points, colors);
gleSetJoinStyle (save_style);
glPopMatrix ();
glutSwapBuffers ();
}
/* ------------------ end of file ----------------------------- */
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