From 25a5dc2ea718863af84511491b9184d06a8c2931 Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Tue, 27 Mar 2001 17:08:20 +0000 Subject: [PATCH] moved shadow code into teapot.c --- progs/demos/shadow.c | 119 --------------------------------------------------- progs/demos/shadow.h | 18 -------- progs/demos/teapot.c | 79 +++++++++++++++++++++++++++++++++- 3 files changed, 78 insertions(+), 138 deletions(-) delete mode 100644 progs/demos/shadow.c delete mode 100644 progs/demos/shadow.h diff --git a/progs/demos/shadow.c b/progs/demos/shadow.c deleted file mode 100644 index 0f66b53..0000000 --- a/progs/demos/shadow.c +++ /dev/null @@ -1,119 +0,0 @@ -/** -(c) Copyright 1993, Silicon Graphics, Inc. - -ALL RIGHTS RESERVED - -Permission to use, copy, modify, and distribute this software -for any purpose and without fee is hereby granted, provided -that the above copyright notice appear in all copies and that -both the copyright notice and this permission notice appear in -supporting documentation, and that the name of Silicon -Graphics, Inc. not be used in advertising or publicity -pertaining to distribution of the software without specific, -written prior permission. - -THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU -"AS-IS" AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR -OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF -MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. IN NO -EVENT SHALL SILICON GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE -ELSE FOR ANY DIRECT, SPECIAL, INCIDENTAL, INDIRECT OR -CONSEQUENTIAL DAMAGES OF ANY KIND, OR ANY DAMAGES WHATSOEVER, -INCLUDING WITHOUT LIMITATION, LOSS OF PROFIT, LOSS OF USE, -SAVINGS OR REVENUE, OR THE CLAIMS OF THIRD PARTIES, WHETHER OR -NOT SILICON GRAPHICS, INC. HAS BEEN ADVISED OF THE POSSIBILITY -OF SUCH LOSS, HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, -ARISING OUT OF OR IN CONNECTION WITH THE POSSESSION, USE OR -PERFORMANCE OF THIS SOFTWARE. - -US Government Users Restricted Rights - -Use, duplication, or disclosure by the Government is subject to -restrictions set forth in FAR 52.227.19(c)(2) or subparagraph -(c)(1)(ii) of the Rights in Technical Data and Computer -Software clause at DFARS 252.227-7013 and/or in similar or -successor clauses in the FAR or the DOD or NASA FAR -Supplement. Unpublished-- rights reserved under the copyright -laws of the United States. Contractor/manufacturer is Silicon -Graphics, Inc., 2011 N. Shoreline Blvd., Mountain View, CA -94039-7311. - -OpenGL(TM) is a trademark of Silicon Graphics, Inc. -*/ - -/* Taken from the projshadow.c - by Tom McReynolds, SGI */ - -/* Modified by David Bucciarelli */ - -/* Rendering shadows using projective shadows. */ - -#include -#include "shadow.h" - - -enum { - X, Y, Z, W -}; -enum { - A, B, C, D -}; - -/* create a matrix that will project the desired shadow */ -void -shadowmatrix(GLfloat shadowMat[4][4], - GLfloat groundplane[4], - GLfloat lightpos[4]) -{ - GLfloat dot; - - /* find dot product between light position vector and ground plane normal */ - dot = groundplane[X] * lightpos[X] + - groundplane[Y] * lightpos[Y] + - groundplane[Z] * lightpos[Z] + - groundplane[W] * lightpos[W]; - - shadowMat[0][0] = dot - lightpos[X] * groundplane[X]; - shadowMat[1][0] = 0.f - lightpos[X] * groundplane[Y]; - shadowMat[2][0] = 0.f - lightpos[X] * groundplane[Z]; - shadowMat[3][0] = 0.f - lightpos[X] * groundplane[W]; - - shadowMat[X][1] = 0.f - lightpos[Y] * groundplane[X]; - shadowMat[1][1] = dot - lightpos[Y] * groundplane[Y]; - shadowMat[2][1] = 0.f - lightpos[Y] * groundplane[Z]; - shadowMat[3][1] = 0.f - lightpos[Y] * groundplane[W]; - - shadowMat[X][2] = 0.f - lightpos[Z] * groundplane[X]; - shadowMat[1][2] = 0.f - lightpos[Z] * groundplane[Y]; - shadowMat[2][2] = dot - lightpos[Z] * groundplane[Z]; - shadowMat[3][2] = 0.f - lightpos[Z] * groundplane[W]; - - shadowMat[X][3] = 0.f - lightpos[W] * groundplane[X]; - shadowMat[1][3] = 0.f - lightpos[W] * groundplane[Y]; - shadowMat[2][3] = 0.f - lightpos[W] * groundplane[Z]; - shadowMat[3][3] = dot - lightpos[W] * groundplane[W]; - -} - -/* find the plane equation given 3 points */ -void -findplane(GLfloat plane[4], - GLfloat v0[3], GLfloat v1[3], GLfloat v2[3]) -{ - GLfloat vec0[3], vec1[3]; - - /* need 2 vectors to find cross product */ - vec0[X] = v1[X] - v0[X]; - vec0[Y] = v1[Y] - v0[Y]; - vec0[Z] = v1[Z] - v0[Z]; - - vec1[X] = v2[X] - v0[X]; - vec1[Y] = v2[Y] - v0[Y]; - vec1[Z] = v2[Z] - v0[Z]; - - /* find cross product to get A, B, and C of plane equation */ - plane[A] = vec0[Y] * vec1[Z] - vec0[Z] * vec1[Y]; - plane[B] = -(vec0[X] * vec1[Z] - vec0[Z] * vec1[X]); - plane[C] = vec0[X] * vec1[Y] - vec0[Y] * vec1[X]; - - plane[D] = -(plane[A] * v0[X] + plane[B] * v0[Y] + plane[C] * v0[Z]); -} diff --git a/progs/demos/shadow.h b/progs/demos/shadow.h deleted file mode 100644 index b19dd43..0000000 --- a/progs/demos/shadow.h +++ /dev/null @@ -1,18 +0,0 @@ -#ifndef SHADOW_H -#define SHADOW_H - - -extern void -shadowmatrix(GLfloat shadowMat[4][4], - GLfloat groundplane[4], - GLfloat lightpos[4]); - - -extern void -findplane(GLfloat plane[4], - GLfloat v0[3], GLfloat v1[3], GLfloat v2[3]); - - -#endif - - diff --git a/progs/demos/teapot.c b/progs/demos/teapot.c index cb1ba4b..dd2eadf 100644 --- a/progs/demos/teapot.c +++ b/progs/demos/teapot.c @@ -17,7 +17,6 @@ #include #include "readtex.c" -#include "shadow.c" #ifdef XMESA #include "GL/xmesa.h" @@ -66,6 +65,84 @@ static int joyactive=0; static GLuint t1id,t2id; static GLuint teapotdlist,basedlist,lightdlist; + + +/******************** begin shadow code ********************/ + +/* Taken from the projshadow.c - by Tom McReynolds, SGI */ + +/* Modified by David Bucciarelli */ + +enum { + X, Y, Z, W +}; +enum { + A, B, C, D +}; + +/* create a matrix that will project the desired shadow */ +void +shadowmatrix(GLfloat shadowMat[4][4], + GLfloat groundplane[4], + GLfloat lightpos[4]) +{ + GLfloat dot; + + /* find dot product between light position vector and ground plane normal */ + dot = groundplane[X] * lightpos[X] + + groundplane[Y] * lightpos[Y] + + groundplane[Z] * lightpos[Z] + + groundplane[W] * lightpos[W]; + + shadowMat[0][0] = dot - lightpos[X] * groundplane[X]; + shadowMat[1][0] = 0.f - lightpos[X] * groundplane[Y]; + shadowMat[2][0] = 0.f - lightpos[X] * groundplane[Z]; + shadowMat[3][0] = 0.f - lightpos[X] * groundplane[W]; + + shadowMat[X][1] = 0.f - lightpos[Y] * groundplane[X]; + shadowMat[1][1] = dot - lightpos[Y] * groundplane[Y]; + shadowMat[2][1] = 0.f - lightpos[Y] * groundplane[Z]; + shadowMat[3][1] = 0.f - lightpos[Y] * groundplane[W]; + + shadowMat[X][2] = 0.f - lightpos[Z] * groundplane[X]; + shadowMat[1][2] = 0.f - lightpos[Z] * groundplane[Y]; + shadowMat[2][2] = dot - lightpos[Z] * groundplane[Z]; + shadowMat[3][2] = 0.f - lightpos[Z] * groundplane[W]; + + shadowMat[X][3] = 0.f - lightpos[W] * groundplane[X]; + shadowMat[1][3] = 0.f - lightpos[W] * groundplane[Y]; + shadowMat[2][3] = 0.f - lightpos[W] * groundplane[Z]; + shadowMat[3][3] = dot - lightpos[W] * groundplane[W]; + +} + +/* find the plane equation given 3 points */ +void +findplane(GLfloat plane[4], + GLfloat v0[3], GLfloat v1[3], GLfloat v2[3]) +{ + GLfloat vec0[3], vec1[3]; + + /* need 2 vectors to find cross product */ + vec0[X] = v1[X] - v0[X]; + vec0[Y] = v1[Y] - v0[Y]; + vec0[Z] = v1[Z] - v0[Z]; + + vec1[X] = v2[X] - v0[X]; + vec1[Y] = v2[Y] - v0[Y]; + vec1[Z] = v2[Z] - v0[Z]; + + /* find cross product to get A, B, and C of plane equation */ + plane[A] = vec0[Y] * vec1[Z] - vec0[Z] * vec1[Y]; + plane[B] = -(vec0[X] * vec1[Z] - vec0[Z] * vec1[X]); + plane[C] = vec0[X] * vec1[Y] - vec0[Y] * vec1[X]; + + plane[D] = -(plane[A] * v0[X] + plane[B] * v0[Y] + plane[C] * v0[Z]); +} + +/******************** end shadow code ********************/ + + static void calcposobs(void) { dir[0]=sin(alpha*M_PI/180.0); -- 2.7.4