OBJECTS.CXX
/******************************Module*Header*******************************\
* Module Name: objects.cxx
*
* Creates command lists for pipe primitive objects
*
* Copyright (c) 1994 Microsoft Corporation
*
\**************************************************************************/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>
#include <windows.h>
#include <GL/gl.h>
#include "sscommon.h"
#include "objects.h"
#include "sspipes.h"
#define ROOT_TWO 1.414213562373f
/**************************************************************************\
* OBJECT constructor
*
\**************************************************************************/
OBJECT::OBJECT( )
{
listNum = glGenLists(1);
}
/**************************************************************************\
* OBJECT destructor
*
\**************************************************************************/
OBJECT::~OBJECT( )
{
glDeleteLists( listNum, 1 );
}
/**************************************************************************\
* Draw
*
* - Draw the object by calling its display list
*
\**************************************************************************/
void
OBJECT::Draw( )
{
glCallList( listNum );
}
/**************************************************************************\
* PIPE_OBJECT constructors
*
\**************************************************************************/
PIPE_OBJECT::PIPE_OBJECT( OBJECT_BUILD_INFO *pBuildInfo, float len )
{
Build( pBuildInfo, len, 0.0f, 0.0f );
}
PIPE_OBJECT::PIPE_OBJECT( OBJECT_BUILD_INFO *pBuildInfo, float len, float s_start, float s_end )
{
Build( pBuildInfo, len, s_start, s_end );
}
/**************************************************************************\
* ELBOW_OBJECT constructors
*
\**************************************************************************/
ELBOW_OBJECT::ELBOW_OBJECT( OBJECT_BUILD_INFO *pBuildInfo, int notch )
{
Build( pBuildInfo, notch, 0.0f, 0.0f );
}
ELBOW_OBJECT::ELBOW_OBJECT( OBJECT_BUILD_INFO *pBuildInfo, int notch, float s_start, float s_end )
{
Build( pBuildInfo, notch, s_start, s_end );
}
/**************************************************************************\
* BALLJOINT_OBJECT constructor
*
\**************************************************************************/
BALLJOINT_OBJECT::BALLJOINT_OBJECT( OBJECT_BUILD_INFO *pBuildInfo, int notch, float s_start, float s_end )
{
Build( pBuildInfo, notch, s_start, s_end );
}
/**************************************************************************\
* SPHERE_OBJECT constructors
*
\**************************************************************************/
SPHERE_OBJECT::SPHERE_OBJECT( OBJECT_BUILD_INFO *pBuildInfo, float radius )
{
Build( pBuildInfo, radius, 0.0f, 0.0f );
}
SPHERE_OBJECT::SPHERE_OBJECT( OBJECT_BUILD_INFO *pBuildInfo, float radius, float s_start, float s_end )
{
Build( pBuildInfo, radius, s_start, s_end );
}
// rotate circle around x-axis, with edge attached to anchor
static void TransformCircle(
float angle,
POINT3D *inPoint,
POINT3D *outPoint,
GLint num,
POINT3D *anchor )
{
MATRIX matrix1, matrix2, matrix3;
int i;
// translate anchor point to origin
ss_matrixIdent( &matrix1 );
ss_matrixTranslate( &matrix1, -anchor->x, -anchor->y, -anchor->z );
// rotate by angle, cw around x-axis
ss_matrixIdent( &matrix2 );
ss_matrixRotate( &matrix2, (double) -angle, 0.0, 0.0 );
// concat these 2
ss_matrixMult( &matrix3, &matrix2, &matrix1 );
// translate back
ss_matrixIdent( &matrix2 );
ss_matrixTranslate( &matrix2, anchor->x, anchor->y, anchor->z );
// concat these 2
ss_matrixMult( &matrix1, &matrix2, &matrix3 );
// transform all the points, + center
for( i = 0; i < num; i ++, outPoint++, inPoint++ ) {
ss_xformPoint( outPoint, inPoint, &matrix1 );
}
}
static void CalcNormals( POINT3D *p, POINT3D *n, POINT3D *center,
int num )
{
int i;
for( i = 0; i < num; i ++, n++, p++ ) {
n->x = p->x - center->x;
n->y = p->y - center->y;
n->z = p->z - center->z;
ss_normalizeNorm( n );
}
}
/*----------------------------------------------------------------------\
| MakeQuadStrip() |
| - builds quadstrip between 2 rows of points. pA points to one |
| row of points, and pB to the next rotated row. Because |
| the rotation has previously been defined CCW around the |
| x-axis, using an A-B sequence will result in CCW quads |
| |
\----------------------------------------------------------------------*/
static void MakeQuadStrip
(
POINT3D *pA,
POINT3D *pB,
POINT3D *nA,
POINT3D *nB,
BOOL bTexture,
GLfloat *tex_s,
GLfloat *tex_t,
GLint slices
)
{
GLint i;
glBegin( GL_QUAD_STRIP );
for( i = 0; i < slices; i ++ ) {
glNormal3fv( (GLfloat *) nA++ );
if( bTexture )
glTexCoord2f( tex_s[0], *tex_t );
glVertex3fv( (GLfloat *) pA++ );
glNormal3fv( (GLfloat *) nB++ );
if( bTexture )
glTexCoord2f( tex_s[1], *tex_t++ );
glVertex3fv( (GLfloat *) pB++ );
}
glEnd();
}
#define CACHE_SIZE 100
/*----------------------------------------------------------------------\
| BuildElbow() |
| - builds elbows, by rotating a circle in the y=r plane |
| centered at (0,r,-r), CW around the x-axis at anchor pt. |
| (r = radius of the circle) |
| - rotation is 90.0 degrees, ending at circle in z=0 plane, |
| centered at origin. |
| - in order to 'mate' texture coords with the cylinders |
| generated with glu, we generate 4 elbows, each corresponding |
| to the 4 possible CW 90 degree orientations of the start point|
| for each circle. |
| - We call this start point the 'notch'. If we characterize |
| each notch by the axis it points down in the starting and |
| ending circles of the elbow, then we get the following axis |
| pairs for our 4 notches: |
| - +z,+y |
| - +x,+x |
| - -z,-y |
| - -x,-x |
| Since the start of the elbow always points down +y, the 4 |
| start notches give all possible 90.0 degree orientations |
| around y-axis. |
| - We can keep track of the current 'notch' vector to provide |
| proper mating between primitives. |
| - Each circle of points is described CW from the start point, |
| assuming looking down the +y axis(+y direction). |
| - texture 's' starts at 0.0, and goes to 2.0*r/divSize at |
| end of the elbow. (Then a short pipe would start with this |
| 's', and run it to 1.0). |
| |
\----------------------------------------------------------------------*/
void
ELBOW_OBJECT::Build( OBJECT_BUILD_INFO *pBuildInfo, int notch, float s_start, float s_end )
{
GLint stacks, slices;
GLfloat angle, startAng;
GLint numPoints;
GLfloat s_delta;
POINT3D pi[CACHE_SIZE]; // initial row of points + center
POINT3D p0[CACHE_SIZE]; // 2 rows of points
POINT3D p1[CACHE_SIZE];
POINT3D n0[CACHE_SIZE]; // 2 rows of normals
POINT3D n1[CACHE_SIZE];
GLfloat tex_t[CACHE_SIZE];// 't' texture coords
GLfloat tex_s[2]; // 's' texture coords
POINT3D center; // center of circle
POINT3D anchor; // where circle is anchored
POINT3D *pA, *pB, *nA, *nB;
int i;
IPOINT2D *texRep = pBuildInfo->texRep;
GLfloat radius = pBuildInfo->radius;
BOOL bTexture = pBuildInfo->bTexture;
slices = pBuildInfo->nSlices;
stacks = slices / 2;
if (slices >= CACHE_SIZE) slices = CACHE_SIZE-1;
if (stacks >= CACHE_SIZE) stacks = CACHE_SIZE-1;
s_delta = s_end - s_start;
if( bTexture ) {
// calculate 't' texture coords
for( i = 0; i <= slices; i ++ ) {
tex_t[i] = (GLfloat) i * texRep->y / slices;
}
}
numPoints = slices + 1;
// starting angle increment 90.0 degrees each time
startAng = notch * PI / 2;
// calc initial circle of points for circle centered at 0,r,-r
// points start at (0,r,0), and rotate circle CCW
for( i = 0; i <= slices; i ++ ) {
angle = startAng + (2 * PI * i / slices);
pi[i].x = radius * (float) sin(angle);
pi[i].y = radius;
// translate z by -r, cuz these cos calcs are for circle at origin
pi[i].z = radius * (float) cos(angle) - radius;
}
// center point, tacked onto end of circle of points
pi[i].x = 0.0f;
pi[i].y = radius;
pi[i].z = -radius;
center = pi[i];
// anchor point
anchor.x = anchor.z = 0.0f;
anchor.y = radius;
// calculate initial normals
CalcNormals( pi, n0, ¢er, numPoints );
// initial 's' texture coordinate
tex_s[0] = s_start;
// setup pointers
pA = pi;
pB = p0;
nA = n0;
nB = n1;
// now iterate throught the stacks
glNewList(listNum, GL_COMPILE);
for( i = 1; i <= stacks; i ++ ) {
// ! this angle must be negative, for correct vertex orientation !
angle = - 0.5f * PI * i / stacks;
// transform to get next circle of points + center
TransformCircle( angle, pi, pB, numPoints+1, &anchor );
// calculate normals
center = pB[numPoints];
CalcNormals( pB, nB, ¢er, numPoints );
// calculate next 's' texture coord
tex_s[1] = (GLfloat) s_start + s_delta * i / stacks;
// now we've got points and normals, ready to be quadstrip'd
MakeQuadStrip( pA, pB, nA, nB, bTexture, tex_s, tex_t, numPoints );
// reset pointers
pA = pB;
nA = nB;
pB = (pB == p0) ? p1 : p0;
nB = (nB == n0) ? n1 : n0;
tex_s[0] = tex_s[1];
}
glEndList();
}
/*----------------------------------------------------------------------\
| BuildBallJoint() |
| - These are very similar to the elbows, in that the starting |
| and ending positions are almost identical. The difference |
| here is that the circles in the sweep describe a sphere as |
| they are rotated. |
| |
\----------------------------------------------------------------------*/
void
BALLJOINT_OBJECT::Build( OBJECT_BUILD_INFO *pBuildInfo, int notch,
float s_start, float s_end )
{
GLfloat ballRadius;
GLfloat angle, delta_a, startAng, theta;
GLint numPoints;
GLfloat s_delta;
POINT3D pi0[CACHE_SIZE]; // 2 circles of untransformed points
POINT3D pi1[CACHE_SIZE];
POINT3D p0[CACHE_SIZE]; // 2 rows of transformed points
POINT3D p1[CACHE_SIZE];
POINT3D n0[CACHE_SIZE]; // 2 rows of normals
POINT3D n1[CACHE_SIZE];
float r[CACHE_SIZE]; // radii of the circles
GLfloat tex_t[CACHE_SIZE];// 't' texture coords
GLfloat tex_s[2]; // 's' texture coords
POINT3D center; // center of circle
POINT3D anchor; // where circle is anchored
POINT3D *pA, *pB, *nA, *nB;
int i, k;
GLint stacks, slices;
IPOINT2D *texRep = pBuildInfo->texRep;
GLfloat radius = pBuildInfo->radius;
BOOL bTexture = pBuildInfo->bTexture;
slices = pBuildInfo->nSlices;
stacks = slices;
if (slices >= CACHE_SIZE) slices = CACHE_SIZE-1;
if (stacks >= CACHE_SIZE) stacks = CACHE_SIZE-1;
// calculate the radii for each circle in the sweep, where
// r[i] = y = sin(angle)/r
angle = PI / 4; // first radius always at 45.0 degrees
delta_a = (PI / 2.0f) / stacks;
ballRadius = ROOT_TWO * radius;
for( i = 0; i <= stacks; i ++, angle += delta_a ) {
r[i] = (float) sin(angle) * ballRadius;
}
if( bTexture ) {
// calculate 't' texture coords
for( i = 0; i <= slices; i ++ ) {
tex_t[i] = (GLfloat) i * texRep->y / slices;
}
}
s_delta = s_end - s_start;
numPoints = slices + 1;
// unlike the elbow, the center for the ball joint is constant
center.x = center.y = 0.0f;
center.z = -radius;
// starting angle along circle, increment 90.0 degrees each time
startAng = notch * PI / 2;
// calc initial circle of points for circle centered at 0,r,-r
// points start at (0,r,0), and rotate circle CCW
delta_a = 2 * PI / slices;
for( i = 0, theta = startAng; i <= slices; i ++, theta += delta_a ) {
pi0[i].x = r[0] * (float) sin(theta);
pi0[i].y = radius;
// translate z by -r, cuz these cos calcs are for circle at origin
pi0[i].z = r[0] * (float) cos(theta) - r[0];
}
// anchor point
anchor.x = anchor.z = 0.0f;
anchor.y = radius;
// calculate initial normals
CalcNormals( pi0, n0, ¢er, numPoints );
// initial 's' texture coordinate
tex_s[0] = s_start;
// setup pointers
pA = pi0; // circles of transformed points
pB = p0;
nA = n0; // circles of transformed normals
nB = n1;
// now iterate throught the stacks
glNewList(listNum, GL_COMPILE);
for( i = 1; i <= stacks; i ++ ) {
// ! this angle must be negative, for correct vertex orientation !
angle = - 0.5f * PI * i / stacks;
// calc the next circle of untransformed points into pi1[]
for( k = 0, theta = startAng; k <= slices; k ++, theta+=delta_a ) {
pi1[k].x = r[i] * (float) sin(theta);
pi1[k].y = radius;
// translate z by -r, cuz calcs are for circle at origin
pi1[k].z = r[i] * (float) cos(theta) - r[i];
}
// rotate cirle of points to next position
TransformCircle( angle, pi1, pB, numPoints, &anchor );
// calculate normals
CalcNormals( pB, nB, ¢er, numPoints );
// calculate next 's' texture coord
tex_s[1] = (GLfloat) s_start + s_delta * i / stacks;
// now we've got points and normals, ready to be quadstrip'd
MakeQuadStrip( pA, pB, nA, nB, bTexture, tex_s, tex_t, numPoints );
// reset pointers
pA = pB;
nA = nB;
pB = (pB == p0) ? p1 : p0;
nB = (nB == n0) ? n1 : n0;
tex_s[0] = tex_s[1];
}
glEndList();
}
// 'glu' routines
#ifdef _EXTENSIONS_
#define COS cosf
#define SIN sinf
#define SQRT sqrtf
#else
#define COS cos
#define SIN sin
#define SQRT sqrt
#endif
/**************************************************************************\
* BuildCylinder
*
\**************************************************************************/
void
PIPE_OBJECT::Build( OBJECT_BUILD_INFO *pBuildInfo, float length, float s_start,
float s_end )
{
GLint stacks, slices;
GLint i,j;
GLfloat sinCache[CACHE_SIZE];
GLfloat cosCache[CACHE_SIZE];
GLfloat sinCache2[CACHE_SIZE];
GLfloat cosCache2[CACHE_SIZE];
GLfloat angle;
GLfloat zLow, zHigh;
GLfloat zNormal;
GLfloat s_delta;
IPOINT2D *texRep = pBuildInfo->texRep;
GLfloat radius = pBuildInfo->radius;
BOOL bTexture = pBuildInfo->bTexture;
slices = pBuildInfo->nSlices;
stacks = (int) SS_ROUND_UP( (length/pBuildInfo->divSize) * (float)slices) ;
if (slices >= CACHE_SIZE) slices = CACHE_SIZE-1;
if (stacks >= CACHE_SIZE) stacks = CACHE_SIZE-1;
zNormal = 0.0f;
s_delta = s_end - s_start;
for (i = 0; i < slices; i++) {
angle = 2 * PI * i / slices;
sinCache2[i] = (float) SIN(angle);
cosCache2[i] = (float) COS(angle);
sinCache[i] = (float) SIN(angle);
cosCache[i] = (float) COS(angle);
}
sinCache[slices] = sinCache[0];
cosCache[slices] = cosCache[0];
sinCache2[slices] = sinCache2[0];
cosCache2[slices] = cosCache2[0];
glNewList(listNum, GL_COMPILE);
for (j = 0; j < stacks; j++) {
zLow = j * length / stacks;
zHigh = (j + 1) * length / stacks;
glBegin(GL_QUAD_STRIP);
for (i = 0; i <= slices; i++) {
glNormal3f(sinCache2[i], cosCache2[i], zNormal);
if (bTexture) {
glTexCoord2f( (float) s_start + s_delta * j / stacks,
(float) i * texRep->y / slices );
}
glVertex3f(radius * sinCache[i],
radius * cosCache[i], zLow);
if (bTexture) {
glTexCoord2f( (float) s_start + s_delta*(j+1) / stacks,
(float) i * texRep->y / slices );
}
glVertex3f(radius * sinCache[i],
radius * cosCache[i], zHigh);
}
glEnd();
}
glEndList();
}
/*----------------------------------------------------------------------\
| pipeSphere() |
| |
\----------------------------------------------------------------------*/
void
SPHERE_OBJECT::Build( OBJECT_BUILD_INFO *pBuildInfo, GLfloat radius,
GLfloat s_start, GLfloat s_end)
{
GLint i,j;
GLfloat sinCache1a[CACHE_SIZE];
GLfloat cosCache1a[CACHE_SIZE];
GLfloat sinCache2a[CACHE_SIZE];
GLfloat cosCache2a[CACHE_SIZE];
GLfloat sinCache1b[CACHE_SIZE];
GLfloat cosCache1b[CACHE_SIZE];
GLfloat sinCache2b[CACHE_SIZE];
GLfloat cosCache2b[CACHE_SIZE];
GLfloat angle;
GLfloat zLow, zHigh;
GLfloat sintemp1, sintemp2, sintemp3, sintemp4;
GLfloat costemp3, costemp4;
GLfloat s_delta;
GLint start, finish;
GLint stacks, slices;
BOOL bTexture = pBuildInfo->bTexture;
IPOINT2D *texRep = pBuildInfo->texRep;
slices = pBuildInfo->nSlices;
stacks = slices;
if (slices >= CACHE_SIZE) slices = CACHE_SIZE-1;
if (stacks >= CACHE_SIZE) stacks = CACHE_SIZE-1;
// invert sense of s - it seems the glu sphere is not built similarly
// to the glu cylinder
// (this probably means stacks don't grow along +z - check it out)
s_delta = s_start;
s_start = s_end;
s_end = s_delta;
s_delta = s_end - s_start;
/* Cache is the vertex locations cache */
/* Cache2 is the various normals at the vertices themselves */
for (i = 0; i < slices; i++) {
angle = 2 * PI * i / slices;
sinCache1a[i] = (float) SIN(angle);
cosCache1a[i] = (float) COS(angle);
sinCache2a[i] = sinCache1a[i];
cosCache2a[i] = cosCache1a[i];
}
for (j = 0; j <= stacks; j++) {
angle = PI * j / stacks;
sinCache2b[j] = (float) SIN(angle);
cosCache2b[j] = (float) COS(angle);
sinCache1b[j] = radius * (float) SIN(angle);
cosCache1b[j] = radius * (float) COS(angle);
}
/* Make sure it comes to a point */
sinCache1b[0] = 0.0f;
sinCache1b[stacks] = 0.0f;
sinCache1a[slices] = sinCache1a[0];
cosCache1a[slices] = cosCache1a[0];
sinCache2a[slices] = sinCache2a[0];
cosCache2a[slices] = cosCache2a[0];
glNewList(listNum, GL_COMPILE);
/* Do ends of sphere as TRIANGLE_FAN's (if not bTexture)
** We don't do it when bTexture because we need to respecify the
** texture coordinates of the apex for every adjacent vertex (because
** it isn't a constant for that point)
*/
if (!bTexture) {
start = 1;
finish = stacks - 1;
/* Low end first (j == 0 iteration) */
sintemp2 = sinCache1b[1];
zHigh = cosCache1b[1];
sintemp3 = sinCache2b[1];
costemp3 = cosCache2b[1];
glNormal3f(sinCache2a[0] * sinCache2b[0],
cosCache2a[0] * sinCache2b[0],
cosCache2b[0]);
glBegin(GL_TRIANGLE_FAN);
glVertex3f(0.0f, 0.0f, radius);
for (i = slices; i >= 0; i--) {
glNormal3f(sinCache2a[i] * sintemp3,
cosCache2a[i] * sintemp3,
costemp3);
glVertex3f(sintemp2 * sinCache1a[i],
sintemp2 * cosCache1a[i], zHigh);
}
glEnd();
/* High end next (j == stacks-1 iteration) */
sintemp2 = sinCache1b[stacks-1];
zHigh = cosCache1b[stacks-1];
sintemp3 = sinCache2b[stacks-1];
costemp3 = cosCache2b[stacks-1];
glNormal3f(sinCache2a[stacks] * sinCache2b[stacks],
cosCache2a[stacks] * sinCache2b[stacks],
cosCache2b[stacks]);
glBegin(GL_TRIANGLE_FAN);
glVertex3f(0.0f, 0.0f, -radius);
for (i = 0; i <= slices; i++) {
glNormal3f(sinCache2a[i] * sintemp3,
cosCache2a[i] * sintemp3,
costemp3);
glVertex3f(sintemp2 * sinCache1a[i],
sintemp2 * cosCache1a[i], zHigh);
}
glEnd();
} else {
start = 0;
finish = stacks;
}
for (j = start; j < finish; j++) {
zLow = cosCache1b[j];
zHigh = cosCache1b[j+1];
sintemp1 = sinCache1b[j];
sintemp2 = sinCache1b[j+1];
sintemp3 = sinCache2b[j+1];
costemp3 = cosCache2b[j+1];
sintemp4 = sinCache2b[j];
costemp4 = cosCache2b[j];
glBegin(GL_QUAD_STRIP);
for (i = 0; i <= slices; i++) {
glNormal3f(sinCache2a[i] * sintemp3,
cosCache2a[i] * sintemp3,
costemp3);
if (bTexture) {
glTexCoord2f( (float) s_start + s_delta*(j+1) / stacks,
(float) i * texRep->y / slices );
}
glVertex3f(sintemp2 * sinCache1a[i],
sintemp2 * cosCache1a[i], zHigh);
glNormal3f(sinCache2a[i] * sintemp4,
cosCache2a[i] * sintemp4,
costemp4);
if (bTexture) {
glTexCoord2f( (float) s_start + s_delta * j / stacks,
(float) i * texRep->y / slices );
}
glVertex3f(sintemp1 * sinCache1a[i],
sintemp1 * cosCache1a[i], zLow);
}
glEnd();
}
glEndList();
}