-/* tube, Copyright (c) 2001, 2003, 2007 Jamie Zawinski <jwz@jwz.org>
+/* tube, Copyright (c) 2001-2010 Jamie Zawinski <jwz@jwz.org>
* Utility functions to create tubes and cones in GL.
*
* Permission to use, copy, modify, distribute, and sell this software and its
#include "tube.h"
+typedef struct { GLfloat x, y, z; } XYZ;
+
static int
unit_tube (int faces, int smooth, int caps_p, int wire_p)
{
GLfloat x, y, x0=0, y0=0;
int z = 0;
+ int arraysize, out;
+ struct { XYZ p; XYZ n; GLfloat s, t; } *array;
+
+ arraysize = (faces+1) * 6;
+ array = (void *) calloc (arraysize, sizeof(*array));
+ if (! array) abort();
+ out = 0;
+
+
+ /* #### texture coords are currently not being computed */
+
+
/* side walls
*/
- glFrontFace(GL_CCW);
- glBegin (wire_p ? GL_LINES : (smooth ? GL_QUAD_STRIP : GL_QUADS));
-
th = 0;
x = 1;
y = 0;
for (i = 0; i < faces; i++)
{
+ array[out].p.x = x; /* bottom point A */
+ array[out].p.y = 0;
+ array[out].p.z = y;
+
if (smooth)
- glNormal3f(x, 0, y);
+ array[out].n = array[out].p; /* its own normal */
else
- glNormal3f(x0, 0, y0);
+ {
+ array[out].n.x = x0; /* mid-plane normal */
+ array[out].n.y = 0;
+ array[out].n.z = y0;
+ }
+ out++;
+
+
+ array[out].p.x = x; /* top point A */
+ array[out].p.y = 1;
+ array[out].p.z = y;
+ array[out].n = array[out-1].n; /* same normal */
+ out++;
- glVertex3f(x, 0, y);
- glVertex3f(x, 1, y);
th += step;
x = cos (th);
x0 = cos (th + s2);
y0 = sin (th + s2);
- glVertex3f(x, 1, y);
- glVertex3f(x, 0, y);
+ array[out].p.x = x; /* top point B */
+ array[out].p.y = 1;
+ array[out].p.z = y;
+ array[out].n = array[out-1].n; /* same normal */
+ out++;
+
+
+ array[out] = array[out-3]; /* bottom point A */
+ out++;
+
+ array[out] = array[out-2]; /* top point B */
+ out++;
+
+ array[out].p.x = x; /* bottom point B */
+ array[out].p.y = 0;
+ array[out].p.z = y;
+ array[out].n = array[out-1].n; /* same normal */
+ out++;
+
+ polys++;
}
+
polys++;
+ if (out >= arraysize) abort();
}
- glEnd();
+
+ glEnableClientState (GL_VERTEX_ARRAY);
+ glEnableClientState (GL_NORMAL_ARRAY);
+ glEnableClientState (GL_TEXTURE_COORD_ARRAY);
+
+ glVertexPointer (3, GL_FLOAT, sizeof(*array), &array[0].p);
+ glNormalPointer ( GL_FLOAT, sizeof(*array), &array[0].n);
+ glTexCoordPointer (2, GL_FLOAT, sizeof(*array), &array[0].s);
+
+ glDrawArrays ((wire_p ? GL_LINES :
+ (smooth ? GL_TRIANGLE_STRIP : GL_TRIANGLES)),
+ 0, out);
+
/* End caps
*/
if (caps_p)
for (z = 0; z <= 1; z++)
{
- glFrontFace(z == 0 ? GL_CCW : GL_CW);
- glNormal3f(0, (z == 0 ? -1 : 1), 0);
- glBegin(wire_p ? GL_LINE_LOOP : GL_TRIANGLE_FAN);
- if (! wire_p) glVertex3f(0, z, 0);
- for (i = 0, th = 0; i <= faces; i++)
+ out = 0;
+ if (! wire_p)
{
+ array[out].p.x = 0;
+ array[out].p.y = z;
+ array[out].p.z = 0;
+
+ array[out].n.x = 0;
+ array[out].n.y = (z == 0 ? -1 : 1);
+ array[out].n.z = 0;
+ out++;
+ }
+
+ th = 0;
+ for (i = (z == 0 ? 0 : faces);
+ (z == 0 ? i <= faces : i >= 0);
+ i += (z == 0 ? 1 : -1)) {
GLfloat x = cos (th);
GLfloat y = sin (th);
- glVertex3f(x, z, y);
- th += step;
+
+ array[out] = array[0]; /* same normal and texture */
+ array[out].p.x = x;
+ array[out].p.y = z;
+ array[out].p.z = y;
+ out++;
+
+ th += (z == 0 ? step : -step);
+
polys++;
+ if (out >= arraysize) abort();
}
- glEnd();
+
+ glVertexPointer (3, GL_FLOAT, sizeof(*array), &array[0].p);
+ glNormalPointer ( GL_FLOAT, sizeof(*array), &array[0].n);
+ glTexCoordPointer (2, GL_FLOAT, sizeof(*array), &array[0].s);
+
+ glDrawArrays ((wire_p ? GL_LINE_LOOP : GL_TRIANGLE_FAN), 0, out);
}
+
return polys;
}
GLfloat th;
GLfloat x, y, x0, y0;
+ int arraysize, out;
+ struct { XYZ p; XYZ n; GLfloat s, t; } *array;
+
+ arraysize = (faces+1) * 3;
+ array = (void *) calloc (arraysize, sizeof(*array));
+ if (! array) abort();
+ out = 0;
+
+
+ /* #### texture coords are currently not being computed */
+
+
/* side walls
*/
- glFrontFace(GL_CW);
- glBegin(wire_p ? GL_LINES : GL_TRIANGLES);
th = 0;
x = 1;
for (i = 0; i < faces; i++)
{
- glNormal3f(x0, 0, y0);
- glVertex3f(0, 1, 0);
+ array[out].p.x = x; /* bottom point A */
+ array[out].p.y = 0;
+ array[out].p.z = y;
+
+ if (smooth)
+ array[out].n = array[out].p; /* its own normal */
+ else
+ {
+ array[out].n.x = x0; /* mid-plane normal */
+ array[out].n.y = 0;
+ array[out].n.z = y0;
+ }
+ out++;
+
+
+ array[out].p.x = 0; /* tip point */
+ array[out].p.y = 1;
+ array[out].p.z = 0;
+
+ array[out].n.x = x0; /* mid-plane normal */
+ array[out].n.y = 0;
+ array[out].n.z = y0;
+ out++;
- if (smooth) glNormal3f(x, 0, y);
- glVertex3f(x, 0, y);
th += step;
x0 = cos (th + s2);
x = cos (th);
y = sin (th);
- if (smooth) glNormal3f(x, 0, y);
- glVertex3f(x, 0, y);
+ array[out].p.x = x; /* bottom point B */
+ array[out].p.y = 0;
+ array[out].p.z = y;
+
+ if (smooth)
+ array[out].n = array[out].p; /* its own normal */
+ else
+ array[out].n = array[out-1].n; /* same normal as other two */
+ out++;
+
+
+ if (out >= arraysize) abort();
polys++;
}
- glEnd();
+
+ glEnableClientState (GL_VERTEX_ARRAY);
+ glEnableClientState (GL_NORMAL_ARRAY);
+ glEnableClientState (GL_TEXTURE_COORD_ARRAY);
+
+ glVertexPointer (3, GL_FLOAT, sizeof(*array), &array[0].p);
+ glNormalPointer ( GL_FLOAT, sizeof(*array), &array[0].n);
+ glTexCoordPointer (2, GL_FLOAT, sizeof(*array), &array[0].s);
+
+ glDrawArrays ((wire_p ? GL_LINES : GL_TRIANGLES), 0, out);
+
/* End cap
*/
if (cap_p)
{
- glFrontFace(GL_CCW);
- glNormal3f(0, -1, 0);
- glBegin(wire_p ? GL_LINE_LOOP : GL_TRIANGLE_FAN);
- if (! wire_p) glVertex3f(0, 0, 0);
+ out = 0;
+
+ if (! wire_p)
+ {
+ array[out].p.x = 0;
+ array[out].p.y = 0;
+ array[out].p.z = 0;
+
+ array[out].n.x = 0;
+ array[out].n.y = -1;
+ array[out].n.z = 0;
+ out++;
+ }
+
for (i = 0, th = 0; i <= faces; i++)
{
GLfloat x = cos (th);
GLfloat y = sin (th);
- glVertex3f(x, 0, y);
+
+ array[out] = array[0]; /* same normal and texture */
+ array[out].p.x = x;
+ array[out].p.y = 0;
+ array[out].p.z = y;
+ out++;
th += step;
polys++;
+ if (out >= arraysize) abort();
}
- glEnd();
+
+ glVertexPointer (3, GL_FLOAT, sizeof(*array), &array[0].p);
+ glNormalPointer ( GL_FLOAT, sizeof(*array), &array[0].n);
+ glTexCoordPointer (2, GL_FLOAT, sizeof(*array), &array[0].s);
+
+ glDrawArrays ((wire_p ? GL_LINE_LOOP : GL_TRIANGLE_FAN), 0, out);
}
+
+ free (array);
+
return polys;
}
projects / xscreensaver / blobdiff