| /* $Id: quadric.c,v 1.8 2000/07/11 14:11:04 brianp Exp $ */ |
| |
| /* |
| * Mesa 3-D graphics library |
| * Version: 3.3 |
| * Copyright (C) 1999-2000 Brian Paul |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Library General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 of the License, or (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Library General Public License for more details. |
| * |
| * You should have received a copy of the GNU Library General Public |
| * License along with this library; if not, write to the Free |
| * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| */ |
| |
| |
| /* TODO: |
| * texture coordinate support |
| * flip normals according to orientation |
| * there's still some inside/outside orientation bugs in possibly all |
| * but the sphere function |
| */ |
| |
| |
| #ifdef PC_HEADER |
| #include "all.h" |
| #else |
| #include <math.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include "gluP.h" |
| #endif |
| |
| |
| |
| #ifndef M_PI |
| # define M_PI (3.1415926) |
| #endif |
| |
| |
| /* |
| * Convert degrees to radians: |
| */ |
| #define DEG_TO_RAD(A) ((A)*(M_PI/180.0)) |
| |
| |
| /* |
| * Sin and Cos for degree angles: |
| */ |
| #define SIND( A ) sin( (A)*(M_PI/180.0) ) |
| #define COSD( A) cos( (A)*(M_PI/180.0) ) |
| |
| |
| /* |
| * Texture coordinates if texture flag is set |
| */ |
| #define TXTR_COORD(x,y) if (qobj->TextureFlag) glTexCoord2f(x,y); |
| |
| |
| |
| struct GLUquadric |
| { |
| GLenum DrawStyle; /* GLU_FILL, LINE, SILHOUETTE, or POINT */ |
| GLenum Orientation; /* GLU_INSIDE or GLU_OUTSIDE */ |
| GLboolean TextureFlag; /* Generate texture coords? */ |
| GLenum Normals; /* GLU_NONE, GLU_FLAT, or GLU_SMOOTH */ |
| void (GLCALLBACK * ErrorFunc) (GLenum err); /* Error handler callback function */ |
| }; |
| |
| |
| |
| /* |
| * Process a GLU error. |
| */ |
| static void |
| quadric_error(GLUquadricObj * qobj, GLenum error, const char *msg) |
| { |
| /* Call the error call back function if any */ |
| if (qobj->ErrorFunc) { |
| (*qobj->ErrorFunc) (error); |
| } |
| /* Print a message to stdout if MESA_DEBUG variable is defined */ |
| if (getenv("MESA_DEBUG")) { |
| fprintf(stderr, "GLUError: %s: %s\n", (char *) gluErrorString(error), |
| msg); |
| } |
| } |
| |
| |
| |
| |
| GLUquadricObj *GLAPIENTRY |
| gluNewQuadric(void) |
| { |
| GLUquadricObj *q; |
| |
| q = (GLUquadricObj *) malloc(sizeof(struct GLUquadric)); |
| if (q) { |
| q->DrawStyle = GLU_FILL; |
| q->Orientation = GLU_OUTSIDE; |
| q->TextureFlag = GL_FALSE; |
| q->Normals = GLU_SMOOTH; |
| q->ErrorFunc = NULL; |
| } |
| return q; |
| } |
| |
| |
| |
| void GLAPIENTRY |
| gluDeleteQuadric(GLUquadricObj * state) |
| { |
| if (state) { |
| free((void *) state); |
| } |
| } |
| |
| |
| |
| /* |
| * Set the drawing style to be GLU_FILL, GLU_LINE, GLU_SILHOUETTE, |
| * or GLU_POINT. |
| */ |
| void GLAPIENTRY |
| gluQuadricDrawStyle(GLUquadricObj * quadObject, GLenum drawStyle) |
| { |
| if (quadObject && (drawStyle == GLU_FILL || drawStyle == GLU_LINE |
| || drawStyle == GLU_SILHOUETTE |
| || drawStyle == GLU_POINT)) { |
| quadObject->DrawStyle = drawStyle; |
| } |
| else { |
| quadric_error(quadObject, GLU_INVALID_ENUM, "qluQuadricDrawStyle"); |
| } |
| } |
| |
| |
| |
| /* |
| * Set the orientation to GLU_INSIDE or GLU_OUTSIDE. |
| */ |
| void GLAPIENTRY |
| gluQuadricOrientation(GLUquadricObj * quadObject, GLenum orientation) |
| { |
| if (quadObject |
| && (orientation == GLU_INSIDE || orientation == GLU_OUTSIDE)) { |
| quadObject->Orientation = orientation; |
| } |
| else { |
| quadric_error(quadObject, GLU_INVALID_ENUM, "qluQuadricOrientation"); |
| } |
| } |
| |
| |
| |
| /* |
| * Set the error handler callback function. |
| */ |
| void GLAPIENTRY |
| gluQuadricCallback(GLUquadricObj * qobj, |
| GLenum which, void (GLCALLBACK * fn) ()) |
| { |
| /* |
| * UGH, this is a mess! I thought ANSI was a standard. |
| */ |
| if (qobj && which == GLU_ERROR) { |
| #ifdef __CYGWIN32__ |
| qobj->ErrorFunc = (void (GLCALLBACKPCAST) (GLenum)) fn; |
| #elif defined(OPENSTEP) |
| qobj->ErrorFunc = (void (*)(GLenum)) fn; |
| #elif defined(_WIN32) |
| qobj->ErrorFunc = (void (GLCALLBACK *) (int)) fn; |
| #elif defined(__STORM__) |
| qobj->ErrorFunc = (void (GLCALLBACK *) (GLenum)) fn; |
| #elif defined(__BEOS__) |
| qobj->ErrorFunc = (void (*)(GLenum)) fn; |
| #else |
| qobj->ErrorFunc = (void (GLCALLBACK *) ()) fn; |
| #endif |
| } |
| } |
| |
| |
| void GLAPIENTRY |
| gluQuadricNormals(GLUquadricObj * quadObject, GLenum normals) |
| { |
| if (quadObject |
| && (normals == GLU_NONE || normals == GLU_FLAT |
| || normals == GLU_SMOOTH)) { |
| quadObject->Normals = normals; |
| } |
| } |
| |
| |
| void GLAPIENTRY |
| gluQuadricTexture(GLUquadricObj * quadObject, GLboolean textureCoords) |
| { |
| if (quadObject) { |
| quadObject->TextureFlag = textureCoords; |
| } |
| } |
| |
| |
| |
| |
| /* |
| * Call glNormal3f after scaling normal to unit length. |
| */ |
| static void |
| normal3f(GLfloat x, GLfloat y, GLfloat z) |
| { |
| GLdouble mag; |
| |
| mag = sqrt(x * x + y * y + z * z); |
| if (mag > 0.00001F) { |
| x /= mag; |
| y /= mag; |
| z /= mag; |
| } |
| glNormal3f(x, y, z); |
| } |
| |
| |
| |
| void GLAPIENTRY |
| gluCylinder(GLUquadricObj * qobj, |
| GLdouble baseRadius, GLdouble topRadius, |
| GLdouble height, GLint slices, GLint stacks) |
| { |
| GLdouble da, r, dr, dz; |
| GLfloat x, y, z, nz, nsign; |
| GLint i, j; |
| |
| if (qobj->Orientation == GLU_INSIDE) { |
| nsign = -1.0; |
| } |
| else { |
| nsign = 1.0; |
| } |
| |
| da = 2.0 * M_PI / slices; |
| dr = (topRadius - baseRadius) / stacks; |
| dz = height / stacks; |
| nz = (baseRadius - topRadius) / height; /* Z component of normal vectors */ |
| |
| if (qobj->DrawStyle == GLU_POINT) { |
| glBegin(GL_POINTS); |
| for (i = 0; i < slices; i++) { |
| x = cos(i * da); |
| y = sin(i * da); |
| normal3f(x * nsign, y * nsign, nz * nsign); |
| |
| z = 0.0; |
| r = baseRadius; |
| for (j = 0; j <= stacks; j++) { |
| glVertex3f(x * r, y * r, z); |
| z += dz; |
| r += dr; |
| } |
| } |
| glEnd(); |
| } |
| else if (qobj->DrawStyle == GLU_LINE || qobj->DrawStyle == GLU_SILHOUETTE) { |
| /* Draw rings */ |
| if (qobj->DrawStyle == GLU_LINE) { |
| z = 0.0; |
| r = baseRadius; |
| for (j = 0; j <= stacks; j++) { |
| glBegin(GL_LINE_LOOP); |
| for (i = 0; i < slices; i++) { |
| x = cos(i * da); |
| y = sin(i * da); |
| normal3f(x * nsign, y * nsign, nz * nsign); |
| glVertex3f(x * r, y * r, z); |
| } |
| glEnd(); |
| z += dz; |
| r += dr; |
| } |
| } |
| else { |
| /* draw one ring at each end */ |
| if (baseRadius != 0.0) { |
| glBegin(GL_LINE_LOOP); |
| for (i = 0; i < slices; i++) { |
| x = cos(i * da); |
| y = sin(i * da); |
| normal3f(x * nsign, y * nsign, nz * nsign); |
| glVertex3f(x * baseRadius, y * baseRadius, 0.0); |
| } |
| glEnd(); |
| glBegin(GL_LINE_LOOP); |
| for (i = 0; i < slices; i++) { |
| x = cos(i * da); |
| y = sin(i * da); |
| normal3f(x * nsign, y * nsign, nz * nsign); |
| glVertex3f(x * topRadius, y * topRadius, height); |
| } |
| glEnd(); |
| } |
| } |
| /* draw length lines */ |
| glBegin(GL_LINES); |
| for (i = 0; i < slices; i++) { |
| x = cos(i * da); |
| y = sin(i * da); |
| normal3f(x * nsign, y * nsign, nz * nsign); |
| glVertex3f(x * baseRadius, y * baseRadius, 0.0); |
| glVertex3f(x * topRadius, y * topRadius, height); |
| } |
| glEnd(); |
| } |
| else if (qobj->DrawStyle == GLU_FILL) { |
| GLfloat ds = 1.0 / slices; |
| GLfloat dt = 1.0 / stacks; |
| GLfloat t = 0.0; |
| z = 0.0; |
| r = baseRadius; |
| for (j = 0; j < stacks; j++) { |
| GLfloat s = 0.0; |
| glBegin(GL_QUAD_STRIP); |
| for (i = 0; i <= slices; i++) { |
| GLfloat x, y; |
| if (i == slices) { |
| x = sin(0.0); |
| y = cos(0.0); |
| } |
| else { |
| x = sin(i * da); |
| y = cos(i * da); |
| } |
| if (nsign == 1.0) { |
| normal3f(x * nsign, y * nsign, nz * nsign); |
| TXTR_COORD(s, t); |
| glVertex3f(x * r, y * r, z); |
| normal3f(x * nsign, y * nsign, nz * nsign); |
| TXTR_COORD(s, t + dt); |
| glVertex3f(x * (r + dr), y * (r + dr), z + dz); |
| } |
| else { |
| normal3f(x * nsign, y * nsign, nz * nsign); |
| TXTR_COORD(s, t); |
| glVertex3f(x * r, y * r, z); |
| normal3f(x * nsign, y * nsign, nz * nsign); |
| TXTR_COORD(s, t + dt); |
| glVertex3f(x * (r + dr), y * (r + dr), z + dz); |
| } |
| s += ds; |
| } /* for slices */ |
| glEnd(); |
| r += dr; |
| t += dt; |
| z += dz; |
| } /* for stacks */ |
| } |
| } |
| |
| |
| |
| |
| |
| void GLAPIENTRY |
| gluSphere(GLUquadricObj * qobj, GLdouble radius, GLint slices, GLint stacks) |
| { |
| GLfloat rho, drho, theta, dtheta; |
| GLfloat x, y, z; |
| GLfloat s, t, ds, dt; |
| GLint i, j, imin, imax; |
| GLboolean normals; |
| GLfloat nsign; |
| |
| if (qobj->Normals == GLU_NONE) { |
| normals = GL_FALSE; |
| } |
| else { |
| normals = GL_TRUE; |
| } |
| if (qobj->Orientation == GLU_INSIDE) { |
| nsign = -1.0; |
| } |
| else { |
| nsign = 1.0; |
| } |
| |
| drho = M_PI / (GLfloat) stacks; |
| dtheta = 2.0 * M_PI / (GLfloat) slices; |
| |
| /* texturing: s goes from 0.0/0.25/0.5/0.75/1.0 at +y/+x/-y/-x/+y axis */ |
| /* t goes from -1.0/+1.0 at z = -radius/+radius (linear along longitudes) */ |
| /* cannot use triangle fan on texturing (s coord. at top/bottom tip varies) */ |
| |
| if (qobj->DrawStyle == GLU_FILL) { |
| if (!qobj->TextureFlag) { |
| /* draw +Z end as a triangle fan */ |
| glBegin(GL_TRIANGLE_FAN); |
| glNormal3f(0.0, 0.0, 1.0); |
| TXTR_COORD(0.5, 1.0); |
| glVertex3f(0.0, 0.0, nsign * radius); |
| for (j = 0; j <= slices; j++) { |
| theta = (j == slices) ? 0.0 : j * dtheta; |
| x = -sin(theta) * sin(drho); |
| y = cos(theta) * sin(drho); |
| z = nsign * cos(drho); |
| if (normals) |
| glNormal3f(x * nsign, y * nsign, z * nsign); |
| glVertex3f(x * radius, y * radius, z * radius); |
| } |
| glEnd(); |
| } |
| |
| ds = 1.0 / slices; |
| dt = 1.0 / stacks; |
| t = 1.0; /* because loop now runs from 0 */ |
| if (qobj->TextureFlag) { |
| imin = 0; |
| imax = stacks; |
| } |
| else { |
| imin = 1; |
| imax = stacks - 1; |
| } |
| |
| /* draw intermediate stacks as quad strips */ |
| for (i = imin; i < imax; i++) { |
| rho = i * drho; |
| glBegin(GL_QUAD_STRIP); |
| s = 0.0; |
| for (j = 0; j <= slices; j++) { |
| theta = (j == slices) ? 0.0 : j * dtheta; |
| x = -sin(theta) * sin(rho); |
| y = cos(theta) * sin(rho); |
| z = nsign * cos(rho); |
| if (normals) |
| glNormal3f(x * nsign, y * nsign, z * nsign); |
| TXTR_COORD(s, t); |
| glVertex3f(x * radius, y * radius, z * radius); |
| x = -sin(theta) * sin(rho + drho); |
| y = cos(theta) * sin(rho + drho); |
| z = nsign * cos(rho + drho); |
| if (normals) |
| glNormal3f(x * nsign, y * nsign, z * nsign); |
| TXTR_COORD(s, t - dt); |
| s += ds; |
| glVertex3f(x * radius, y * radius, z * radius); |
| } |
| glEnd(); |
| t -= dt; |
| } |
| |
| if (!qobj->TextureFlag) { |
| /* draw -Z end as a triangle fan */ |
| glBegin(GL_TRIANGLE_FAN); |
| glNormal3f(0.0, 0.0, -1.0); |
| TXTR_COORD(0.5, 0.0); |
| glVertex3f(0.0, 0.0, -radius * nsign); |
| rho = M_PI - drho; |
| s = 1.0; |
| t = dt; |
| for (j = slices; j >= 0; j--) { |
| theta = (j == slices) ? 0.0 : j * dtheta; |
| x = -sin(theta) * sin(rho); |
| y = cos(theta) * sin(rho); |
| z = nsign * cos(rho); |
| if (normals) |
| glNormal3f(x * nsign, y * nsign, z * nsign); |
| TXTR_COORD(s, t); |
| s -= ds; |
| glVertex3f(x * radius, y * radius, z * radius); |
| } |
| glEnd(); |
| } |
| } |
| else if (qobj->DrawStyle == GLU_LINE || qobj->DrawStyle == GLU_SILHOUETTE) { |
| /* draw stack lines */ |
| for (i = 1; i < stacks; i++) { /* stack line at i==stacks-1 was missing here */ |
| rho = i * drho; |
| glBegin(GL_LINE_LOOP); |
| for (j = 0; j < slices; j++) { |
| theta = j * dtheta; |
| x = cos(theta) * sin(rho); |
| y = sin(theta) * sin(rho); |
| z = cos(rho); |
| if (normals) |
| glNormal3f(x * nsign, y * nsign, z * nsign); |
| glVertex3f(x * radius, y * radius, z * radius); |
| } |
| glEnd(); |
| } |
| /* draw slice lines */ |
| for (j = 0; j < slices; j++) { |
| theta = j * dtheta; |
| glBegin(GL_LINE_STRIP); |
| for (i = 0; i <= stacks; i++) { |
| rho = i * drho; |
| x = cos(theta) * sin(rho); |
| y = sin(theta) * sin(rho); |
| z = cos(rho); |
| if (normals) |
| glNormal3f(x * nsign, y * nsign, z * nsign); |
| glVertex3f(x * radius, y * radius, z * radius); |
| } |
| glEnd(); |
| } |
| } |
| else if (qobj->DrawStyle == GLU_POINT) { |
| /* top and bottom-most points */ |
| glBegin(GL_POINTS); |
| if (normals) |
| glNormal3f(0.0, 0.0, nsign); |
| glVertex3d(0.0, 0.0, radius); |
| if (normals) |
| glNormal3f(0.0, 0.0, -nsign); |
| glVertex3d(0.0, 0.0, -radius); |
| |
| /* loop over stacks */ |
| for (i = 1; i < stacks - 1; i++) { |
| rho = i * drho; |
| for (j = 0; j < slices; j++) { |
| theta = j * dtheta; |
| x = cos(theta) * sin(rho); |
| y = sin(theta) * sin(rho); |
| z = cos(rho); |
| if (normals) |
| glNormal3f(x * nsign, y * nsign, z * nsign); |
| glVertex3f(x * radius, y * radius, z * radius); |
| } |
| } |
| glEnd(); |
| } |
| |
| } |
| |
| |
| |
| void GLAPIENTRY |
| gluDisk(GLUquadricObj * qobj, |
| GLdouble innerRadius, GLdouble outerRadius, GLint slices, GLint loops) |
| { |
| GLfloat da, dr; |
| #if 0 |
| GLdouble a, da; |
| GLfloat r, dr; |
| GLfloat x, y; |
| GLfloat r1, r2, dtc; |
| GLint s, l; |
| #endif |
| |
| /* Normal vectors */ |
| if (qobj->Normals != GLU_NONE) { |
| if (qobj->Orientation == GLU_OUTSIDE) { |
| glNormal3f(0.0, 0.0, +1.0); |
| } |
| else { |
| glNormal3f(0.0, 0.0, -1.0); |
| } |
| } |
| |
| da = 2.0 * M_PI / slices; |
| dr = (outerRadius - innerRadius) / (GLfloat) loops; |
| |
| switch (qobj->DrawStyle) { |
| case GLU_FILL: |
| { |
| /* texture of a gluDisk is a cut out of the texture unit square |
| * x, y in [-outerRadius, +outerRadius]; s, t in [0, 1] |
| * (linear mapping) |
| */ |
| GLfloat dtc = 2.0f * outerRadius; |
| GLfloat sa, ca; |
| GLfloat r1 = innerRadius; |
| GLint l; |
| for (l = 0; l < loops; l++) { |
| GLfloat r2 = r1 + dr; |
| if (qobj->Orientation == GLU_OUTSIDE) { |
| GLint s; |
| glBegin(GL_QUAD_STRIP); |
| for (s = 0; s <= slices; s++) { |
| GLfloat a; |
| if (s == slices) |
| a = 0.0; |
| else |
| a = s * da; |
| sa = sin(a); |
| ca = cos(a); |
| TXTR_COORD(0.5 + sa * r2 / dtc, 0.5 + ca * r2 / dtc); |
| glVertex2f(r2 * sa, r2 * ca); |
| TXTR_COORD(0.5 + sa * r1 / dtc, 0.5 + ca * r1 / dtc); |
| glVertex2f(r1 * sa, r1 * ca); |
| } |
| glEnd(); |
| } |
| else { |
| GLint s; |
| glBegin(GL_QUAD_STRIP); |
| for (s = slices; s >= 0; s--) { |
| GLfloat a; |
| if (s == slices) |
| a = 0.0; |
| else |
| a = s * da; |
| sa = sin(a); |
| ca = cos(a); |
| TXTR_COORD(0.5 - sa * r2 / dtc, 0.5 + ca * r2 / dtc); |
| glVertex2f(r2 * sa, r2 * ca); |
| TXTR_COORD(0.5 - sa * r1 / dtc, 0.5 + ca * r1 / dtc); |
| glVertex2f(r1 * sa, r1 * ca); |
| } |
| glEnd(); |
| } |
| r1 = r2; |
| } |
| break; |
| } |
| case GLU_LINE: |
| { |
| GLint l, s; |
| /* draw loops */ |
| for (l = 0; l <= loops; l++) { |
| GLfloat r = innerRadius + l * dr; |
| glBegin(GL_LINE_LOOP); |
| for (s = 0; s < slices; s++) { |
| GLfloat a = s * da; |
| glVertex2f(r * sin(a), r * cos(a)); |
| } |
| glEnd(); |
| } |
| /* draw spokes */ |
| for (s = 0; s < slices; s++) { |
| GLfloat a = s * da; |
| GLfloat x = sin(a); |
| GLfloat y = cos(a); |
| glBegin(GL_LINE_STRIP); |
| for (l = 0; l <= loops; l++) { |
| GLfloat r = innerRadius + l * dr; |
| glVertex2f(r * x, r * y); |
| } |
| glEnd(); |
| } |
| break; |
| } |
| case GLU_POINT: |
| { |
| GLint s; |
| glBegin(GL_POINTS); |
| for (s = 0; s < slices; s++) { |
| GLfloat a = s * da; |
| GLfloat x = sin(a); |
| GLfloat y = cos(a); |
| GLint l; |
| for (l = 0; l <= loops; l++) { |
| GLfloat r = innerRadius * l * dr; |
| glVertex2f(r * x, r * y); |
| } |
| } |
| glEnd(); |
| break; |
| } |
| case GLU_SILHOUETTE: |
| { |
| if (innerRadius != 0.0) { |
| GLfloat a; |
| glBegin(GL_LINE_LOOP); |
| for (a = 0.0; a < 2.0 * M_PI; a += da) { |
| GLfloat x = innerRadius * sin(a); |
| GLfloat y = innerRadius * cos(a); |
| glVertex2f(x, y); |
| } |
| glEnd(); |
| } |
| { |
| GLfloat a; |
| glBegin(GL_LINE_LOOP); |
| for (a = 0; a < 2.0 * M_PI; a += da) { |
| GLfloat x = outerRadius * sin(a); |
| GLfloat y = outerRadius * cos(a); |
| glVertex2f(x, y); |
| } |
| glEnd(); |
| } |
| break; |
| } |
| default: |
| abort(); |
| } |
| } |
| |
| |
| |
| void GLAPIENTRY |
| gluPartialDisk(GLUquadricObj * qobj, GLdouble innerRadius, |
| GLdouble outerRadius, GLint slices, GLint loops, |
| GLdouble startAngle, GLdouble sweepAngle) |
| { |
| if (qobj->Normals != GLU_NONE) { |
| if (qobj->Orientation == GLU_OUTSIDE) { |
| glNormal3f(0.0, 0.0, +1.0); |
| } |
| else { |
| glNormal3f(0.0, 0.0, -1.0); |
| } |
| } |
| |
| if (qobj->DrawStyle == GLU_POINT) { |
| GLint loop, slice; |
| GLdouble radius, delta_radius; |
| GLdouble angle, delta_angle; |
| delta_radius = (outerRadius - innerRadius) / (loops - 1); |
| delta_angle = DEG_TO_RAD((sweepAngle) / (slices - 1)); |
| glBegin(GL_POINTS); |
| radius = innerRadius; |
| for (loop = 0; loop < loops; loop++) { |
| angle = DEG_TO_RAD(startAngle); |
| for (slice = 0; slice < slices; slice++) { |
| glVertex2d(radius * sin(angle), radius * cos(angle)); |
| angle += delta_angle; |
| } |
| radius += delta_radius; |
| } |
| glEnd(); |
| } |
| else if (qobj->DrawStyle == GLU_LINE) { |
| GLint loop, slice; |
| GLdouble radius, delta_radius; |
| GLdouble angle, delta_angle; |
| delta_radius = (outerRadius - innerRadius) / loops; |
| delta_angle = DEG_TO_RAD(sweepAngle / slices); |
| /* draw rings */ |
| radius = innerRadius; |
| for (loop = 0; loop < loops; loop++) { |
| angle = DEG_TO_RAD(startAngle); |
| glBegin(GL_LINE_STRIP); |
| for (slice = 0; slice <= slices; slice++) { |
| glVertex2d(radius * sin(angle), radius * cos(angle)); |
| angle += delta_angle; |
| } |
| glEnd(); |
| radius += delta_radius; |
| } |
| /* draw spokes */ |
| angle = DEG_TO_RAD(startAngle); |
| for (slice = 0; slice <= slices; slice++) { |
| radius = innerRadius; |
| glBegin(GL_LINE_STRIP); |
| for (loop = 0; loop < loops; loop++) { |
| glVertex2d(radius * sin(angle), radius * cos(angle)); |
| radius += delta_radius; |
| } |
| glEnd(); |
| angle += delta_angle; |
| } |
| } |
| else if (qobj->DrawStyle == GLU_SILHOUETTE) { |
| GLint slice; |
| GLdouble angle, delta_angle; |
| delta_angle = DEG_TO_RAD(sweepAngle / slices); |
| /* draw outer ring */ |
| glBegin(GL_LINE_STRIP); |
| angle = DEG_TO_RAD(startAngle); |
| for (slice = 0; slice <= slices; slice++) { |
| glVertex2d(outerRadius * sin(angle), outerRadius * cos(angle)); |
| angle += delta_angle; |
| } |
| glEnd(); |
| /* draw inner ring */ |
| if (innerRadius > 0.0) { |
| glBegin(GL_LINE_STRIP); |
| angle = DEG_TO_RAD(startAngle); |
| for (slice = 0; slice < slices; slice++) { |
| glVertex2d(innerRadius * sin(angle), innerRadius * cos(angle)); |
| angle += delta_angle; |
| } |
| glEnd(); |
| } |
| /* draw spokes */ |
| if (sweepAngle < 360.0) { |
| GLdouble stopAngle = startAngle + sweepAngle; |
| glBegin(GL_LINES); |
| glVertex2d(innerRadius * SIND(startAngle), |
| innerRadius * COSD(startAngle)); |
| glVertex2d(outerRadius * SIND(startAngle), |
| outerRadius * COSD(startAngle)); |
| glVertex2d(innerRadius * SIND(stopAngle), |
| innerRadius * COSD(stopAngle)); |
| glVertex2d(outerRadius * SIND(stopAngle), |
| outerRadius * COSD(stopAngle)); |
| glEnd(); |
| } |
| } |
| else if (qobj->DrawStyle == GLU_FILL) { |
| GLint loop, slice; |
| GLdouble radius, delta_radius; |
| GLdouble angle, delta_angle; |
| delta_radius = (outerRadius - innerRadius) / loops; |
| delta_angle = DEG_TO_RAD(sweepAngle / slices); |
| radius = innerRadius; |
| for (loop = 0; loop < loops; loop++) { |
| glBegin(GL_QUAD_STRIP); |
| angle = DEG_TO_RAD(startAngle); |
| for (slice = 0; slice <= slices; slice++) { |
| if (qobj->Orientation == GLU_OUTSIDE) { |
| glVertex2d((radius + delta_radius) * sin(angle), |
| (radius + delta_radius) * cos(angle)); |
| glVertex2d(radius * sin(angle), radius * cos(angle)); |
| } |
| else { |
| glVertex2d(radius * sin(angle), radius * cos(angle)); |
| glVertex2d((radius + delta_radius) * sin(angle), |
| (radius + delta_radius) * cos(angle)); |
| } |
| angle += delta_angle; |
| } |
| glEnd(); |
| radius += delta_radius; |
| } |
| } |
| } |