xonotic/misc/tools/brightspot.c
2010-10-12 21:35:12 +02:00

305 lines
7.0 KiB
C

#include <stdio.h>
#include <math.h>
// USAGE: see brightspot.sh (and in the future brightspot.bat)
// It should output the right parameters for the sun direction in q3map2's format.
// But probably is broken.
#define false 0
#define true 1
int flip[6*3] =
{
false, false, true, // "rt"
true, true, true, // "lf"
false, true, false, // "bk"
true, false, false, // "ft"
false, false, true, // "up"
false, false, true // "dn"
};
static const double skyboxtexcoord2f[6*4*2] =
{
// skyside[0]
0, 1,
1, 1,
1, 0,
0, 0,
// skyside[1]
1, 0,
0, 0,
0, 1,
1, 1,
// skyside[2]
1, 1,
1, 0,
0, 0,
0, 1,
// skyside[3]
0, 0,
0, 1,
1, 1,
1, 0,
// skyside[4]
0, 1,
1, 1,
1, 0,
0, 0,
// skyside[5]
0, 1,
1, 1,
1, 0,
0, 0
};
#define GET_SKY_IMAGE(x,y,z) \
(fabs(x)>=fabs(y) && fabs(x)>=fabs(z)) ? (((x) > 0) ? 0 : 1) : \
(fabs(y)>=fabs(x) && fabs(y)>=fabs(z)) ? (((y) > 0) ? 2 : 3) : \
(((z) > 0) ? 4 : 5)
int highest[6] =
{
0,
0,
1,
1,
2,
2
};
static const double skyboxvertex3f[6*4*3] =
{
// skyside[0]
16, -16, 16,
16, -16, -16,
16, 16, -16,
16, 16, 16,
// skyside[1]
-16, 16, 16,
-16, 16, -16,
-16, -16, -16,
-16, -16, 16,
// skyside[2]
16, 16, 16,
16, 16, -16,
-16, 16, -16,
-16, 16, 16,
// skyside[3]
-16, -16, 16,
-16, -16, -16,
16, -16, -16,
16, -16, 16,
// skyside[4]
-16, -16, 16,
16, -16, 16,
16, 16, 16,
-16, 16, 16,
// skyside[5]
16, -16, -16,
-16, -16, -16,
-16, 16, -16,
16, 16, -16
};
void Unmap2f(double x, double y, const double *corners, double *u, double *v)
{
// x - corners[0] == *u * (corners[2] - corners[0]) + *v * (corners[4] - corners[2]);
// y - corners[1] == *u * (corners[3] - corners[1]) + *v * (corners[5] - corners[3]);
double xc0 = x - corners[0];
double yc1 = y - corners[1];
double c20 = corners[2] - corners[0];
double c31 = corners[3] - corners[1];
double c42 = corners[4] - corners[2];
double c53 = corners[5] - corners[3];
// xc0 == *u * c20 + *v * c42;
// yc1 == *u * c31 + *v * c53;
double det = c20 * c53 - c31 * c42;
double du = xc0 * c53 - yc1 * c42;
double dv = c20 * yc1 - c31 * xc0;
*u = du / det;
*v = dv / det;
}
void Map3f(double u, double v, const double *corners, double *x, double *y, double *z)
{
*x = corners[0] + u * (corners[3] - corners[0]) + v * (corners[6] - corners[3]);
*y = corners[1] + u * (corners[4] - corners[1]) + v * (corners[7] - corners[4]);
*z = corners[2] + u * (corners[5] - corners[2]) + v * (corners[8] - corners[5]);
}
void Map2f(double u, double v, const double *corners, double *x, double *y)
{
*x = u * (corners[2] - corners[0]) + v * (corners[4] - corners[2]) + corners[0];
*y = u * (corners[3] - corners[1]) + v * (corners[5] - corners[3]) + corners[1];
}
void Unmap3f(double x, double y, double z, const double *corners, double *u, double *v)
{
//*x = corners[0] + u * (corners[3] - corners[0]) + v * (corners[6] - corners[3]);
//*y = corners[1] + u * (corners[4] - corners[1]) + v * (corners[7] - corners[4]);
//*z = corners[2] + u * (corners[5] - corners[2]) + v * (corners[8] - corners[5]);
// THREE equations, TWO would be better! Let's simply use the two "better" ones
double xc0 = x - corners[0];
double yc1 = y - corners[1];
double zc2 = z - corners[2];
double c30 = corners[3] - corners[0];
double c41 = corners[4] - corners[1];
double c52 = corners[5] - corners[2];
double c63 = corners[6] - corners[3];
double c74 = corners[7] - corners[4];
double c85 = corners[8] - corners[5];
double det_x = c41 * c85 - c52 * c74;
double det_y = c30 * c85 - c52 * c63;
double det_z = c30 * c74 - c41 * c63;
if(fabs(det_x) >= fabs(det_y) && fabs(det_x) >= fabs(det_z))
{
double du = yc1 * c85 - zc2 * c74;
double dv = c41 * zc2 - c52 * yc1;
*u = du / det_x;
*v = dv / det_x;
}
else if(fabs(det_y) >= fabs(det_z))
{
double du = xc0 * c85 - zc2 * c63;
double dv = c30 * zc2 - c52 * xc0;
*u = du / det_y;
*v = dv / det_y;
}
else
{
double du = xc0 * c74 - yc1 * c63;
double dv = c30 * yc1 - c41 * xc0;
*u = du / det_z;
*v = dv / det_z;
}
}
void MapCoord(int pic, int y, int x, double vec[3])
{
int h;
int flipx = flip[3*pic+0];
int flipy = flip[3*pic+1];
int flipdiag = flip[3*pic+2];
double u, v;
if(flipx)
x = 511 - x;
if(flipy)
y = 511 - y;
if(flipdiag)
{
h = x; x = y; y = h;
}
Unmap2f((x + 0.5) / 512.0, (y + 0.5) / 512.0, skyboxtexcoord2f + 4*2*pic, &u, &v);
Map3f(u, v, skyboxvertex3f + 6*2*pic, &vec[0], &vec[1], &vec[2]);
}
void UnmapCoord(const double vec_[3], int *pic, int *y, int *x)
{
int h;
int flipx;
int flipy;
int flipdiag;
double u, v, xx, yy;
double f;
double vec[3];
// identify which pic it is
*pic = GET_SKY_IMAGE(vec_[0], vec_[1], vec_[2]);
f = 16.0/fabs(vec_[highest[*pic]]);
vec[0] = vec_[0] * f;
vec[1] = vec_[1] * f;
vec[2] = vec_[2] * f;
flipx = flip[3*(*pic)+0];
flipy = flip[3*(*pic)+1];
flipdiag = flip[3*(*pic)+2];
*x = *y = 0;
Unmap3f(vec[0], vec[1], vec[2], skyboxvertex3f + 6*2*(*pic), &u, &v);
Map2f(u, v, skyboxtexcoord2f + 4*2*(*pic), &xx, &yy);
*x = (int) (xx * 512.0 + 0.5);
*y = (int) (yy * 512.0 + 0.5);
if(flipdiag)
{
h = *x; *x = *y; *y = h;
}
if(flipy)
*y = 511 - *y;
if(flipx)
*x = 511 - *x;
}
int main(int argc, char **argv)
{
FILE *f;
int i, j, k;
unsigned char picture[6][512][512];
unsigned char max;
double brightvec[3];
double pitch, yaw, l;
if(argc != 2)
{
fprintf(stderr, "Usage: %s imagefile.gray\n", *argv);
return 1;
}
f = fopen(argv[1], "rb");
if(!f)
{
perror("fopen");
return 1;
}
fread(&picture, sizeof(picture), 1, f);
fclose(f);
brightvec[0] = brightvec[1] = brightvec[2] = 0;
max = 0;
for(i = 0; i < 6; ++i)
for(j = 0; j < 512; ++j)
for(k = 0; k < 512; ++k)
if(picture[i][j][k] > max)
max = picture[i][j][k];
for(i = 0; i < 6; ++i)
for(j = 0; j < 512; ++j)
for(k = 0; k < 512; ++k)
{
double vec[3], f;
MapCoord(i, j, k, vec);
f = pow(vec[0]*vec[0] + vec[1]*vec[1] + vec[2]*vec[2], -1.5); // I know what I am doing.
f *= exp(10 * (picture[i][j][k] - max));
brightvec[0] += f * vec[0];
brightvec[1] += f * vec[1];
brightvec[2] += f * vec[2];
}
l = sqrt(brightvec[0]*brightvec[0] + brightvec[1]*brightvec[1] + brightvec[2]*brightvec[2]);
l /= 16;
brightvec[0] /= l;
brightvec[1] /= l;
brightvec[2] /= l;
fprintf(stderr, "vec = %f %f %f\n", brightvec[0], brightvec[1], brightvec[2]);
UnmapCoord(brightvec, &i, &j, &k);
fprintf(stderr, "picture %d pixel (%d %d) value %d\n", i, k, j, picture[i][j][k]);
pitch = atan2(brightvec[2], sqrt(brightvec[0]*brightvec[0] + brightvec[1]*brightvec[1]));
yaw = atan2(brightvec[1], brightvec[0]);
printf("%f %f\n", yaw * 180 / M_PI, pitch * 180 / M_PI);
return 0;
}