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#include "draw_3d.h"
#include <math.h>
vertex point_rotate_around_point (vertex point, vertex center, float rotation_x, float rotation_y, float rotation_z)
{
float x, y, z;
float sx,cx, sy,cy, sz,cz;
float xy,xz, yx,yz, zx,zy;
vertex newpoint;
// Center all the points around 0,0,0
x = point.x - center.x;
y = point.y - center.y;
z = point.z - center.z;
// Precalculate sinus and cosinus for each axis rotation
sx = sin(rotation_x);
cx = cos(rotation_x);
sy = sin(rotation_y);
cy = cos(rotation_y);
sz = sin(rotation_z);
cz = cos(rotation_z);
// Rotation around x
xy = cx*y - sx*z;
xz = sx*y + cx*z;
// Rotation around y
yz = cy*xz - sy*x;
yx = sy*xz + cy*x;
// Rotation around z
zx = cz*yx - sz*xy;
zy = sz*yx + cz*xy;
newpoint.x = zx + center.x;
newpoint.y = zy + center.y;
newpoint.z = yz + center.z;
return newpoint;
}
// Calculate all 8 corners of a cube.
void calculate_cube_corners (vertex pnt[8], vertex center, float size)
{
// Distance from center on any axis.
float dist = size/2;
// Points
// X Y Z
pnt[0].x = center.x+dist; pnt[0].y = center.y+dist; pnt[0].z = center.z+dist; // 0 right, front, upper
pnt[1].x = center.x-dist; pnt[1].y = center.y+dist; pnt[1].z = center.z+dist; // 1 left, front, upper
pnt[2].x = center.x+dist; pnt[2].y = center.y-dist; pnt[2].z = center.z+dist; // 2 right, back, upper
pnt[3].x = center.x-dist; pnt[3].y = center.y-dist; pnt[3].z = center.z+dist; // 3 left, back, uppper
pnt[4].x = center.x+dist; pnt[4].y = center.y+dist; pnt[4].z = center.z-dist; // 4 right, front, lower
pnt[5].x = center.x-dist; pnt[5].y = center.y+dist; pnt[5].z = center.z-dist; // 5 left, front, lower
pnt[6].x = center.x+dist; pnt[6].y = center.y-dist; pnt[6].z = center.z-dist; // 6 right, back, lower
pnt[7].x = center.x-dist; pnt[7].y = center.y-dist; pnt[7].z = center.z-dist; // 7 left, bakc, lower
}
void draw_cube_wireframe (vertex pnt[8])
{
int i;
// upper "lid"
line_3d ((int)pnt[0].x,(int)pnt[0].y,(int)pnt[0].z,(int)pnt[1].x,(int)pnt[1].y,(int)pnt[1].z);
line_3d ((int)pnt[2].x,(int)pnt[2].y,(int)pnt[2].z,(int)pnt[3].x,(int)pnt[3].y,(int)pnt[3].z);
line_3d ((int)pnt[1].x,(int)pnt[1].y,(int)pnt[1].z,(int)pnt[3].x,(int)pnt[3].y,(int)pnt[3].z);
line_3d ((int)pnt[2].x,(int)pnt[2].y,(int)pnt[2].z,(int)pnt[0].x,(int)pnt[0].y,(int)pnt[0].z);
// lower "lid"
line_3d ((int)pnt[4].x,(int)pnt[4].y,(int)pnt[4].z,(int)pnt[5].x,(int)pnt[5].y,(int)pnt[5].z);
line_3d ((int)pnt[6].x,(int)pnt[6].y,(int)pnt[6].z,(int)pnt[7].x,(int)pnt[7].y,(int)pnt[7].z);
line_3d ((int)pnt[5].x,(int)pnt[5].y,(int)pnt[5].z,(int)pnt[7].x,(int)pnt[7].y,(int)pnt[7].z);
line_3d ((int)pnt[6].x,(int)pnt[6].y,(int)pnt[6].z,(int)pnt[4].x,(int)pnt[4].y,(int)pnt[4].z);
// side walls
line_3d ((int)pnt[0].x,(int)pnt[0].y,(int)pnt[0].z,(int)pnt[4].x,(int)pnt[4].y,(int)pnt[4].z);
line_3d ((int)pnt[1].x,(int)pnt[1].y,(int)pnt[1].z,(int)pnt[5].x,(int)pnt[5].y,(int)pnt[5].z);
line_3d ((int)pnt[2].x,(int)pnt[2].y,(int)pnt[2].z,(int)pnt[6].x,(int)pnt[6].y,(int)pnt[6].z);
line_3d ((int)pnt[3].x,(int)pnt[3].y,(int)pnt[3].z,(int)pnt[7].x,(int)pnt[7].y,(int)pnt[7].z);
}
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