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/*
* Copyright © 2009 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
* Authors:
* Eric Anholt <eric@anholt.net>
*
*/
#include <glu3.h>
#include <assert.h>
static GLboolean vec4_equals(const GLUvec4 *a, const GLUvec4 *b)
{
int i;
for (i = 0; i < 4; i++) {
if (a->values[i] != b->values[i])
return GL_FALSE;
}
return GL_TRUE;
}
static void vec4_divide(GLUvec4 *a)
{
a->values[0] /= a->values[3];
a->values[1] /= a->values[3];
a->values[2] /= a->values[3];
a->values[3] = 1.0;
}
int main(int argc, char **argv)
{
GLUvec4 eye = {{0.0, 0.0, 0.0, 0.0}};
GLUvec4 center = {{0.0, 0.0, -1.0, 0.0}};
GLUvec4 up = {{0.0, 1.0, 0.0, 0.0}};
GLUvec4 result;
GLUmat4 identity_lookat;
GLUvec4 a = {{1.0, 2.0, 3.0, 1.0}};
GLUvec4 b = {{-2.0, 3.0, 5.0, 1.0}};
(void)argc;
(void)argv;
gluLookAt4v(&identity_lookat,
&eye,
¢er,
&up);
gluMult4m_4v(&result, &identity_lookat, &a);
vec4_divide(&result);
assert(vec4_equals(&result, &a));
gluMult4m_4v(&result, &identity_lookat, &b);
vec4_divide(&result);
assert(vec4_equals(&result, &b));
/* Make sure that LookAt doesn't take the 4th component
* eye/center/up into account.
*/
eye.values[3] = 1.0;
center.values[3] = 1.0;
up.values[3] = 1.0;
gluLookAt4v(&identity_lookat,
&eye,
¢er,
&up);
gluMult4m_4v(&result, &identity_lookat, &a);
vec4_divide(&result);
assert(vec4_equals(&result, &a));
gluMult4m_4v(&result, &identity_lookat, &b);
vec4_divide(&result);
assert(vec4_equals(&result, &b));
return 0;
}
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