static void motion(int x, int y)
{
float dx, dy;
dx = (float) (x - last_x) / width;
dy = (float) (y - last_y) / height;
if (cur_op == ROTATING) {
y_rot -= dx * 360.0f;
x_rot -= dy * 360.0f;
} else if (cur_op == PANNING) {
float lx, ly;
vector x, y, z;
ly = 2.0f * focal_len * tanf(radians(fovy / 2.0f));
lx = ly * width / height;
get_camera_frame(x, y, z);
vec_mad(center, -dx * lx, x);
vec_mad(center, dy * ly, y);
} else if (cur_op == ZOOMING) {
focal_len *= (1.0f - dy) - dx;
}
last_x = x;
last_y = y;
}
static void get_camera(vector eye, vector at, vector up)
{
vector x, y, z;
get_camera_frame(x, y, z);
vec_copy(at, center);
vec_copy(eye, center);
vec_mad(eye, focal_len, z);
vec_copy(up, y);
}
int main()
{
camera_open();
camera_update();
graphics_open(get_camera_width(), get_camera_height());
while(!get_key_state('Q'))
{
camera_update();
graphics_blit_enc(get_camera_frame(), BGR, 0, 0, get_camera_width(), get_camera_height());
graphics_circle_fill(get_camera_width() / 2, get_camera_height() / 2, get_camera_height() / 20, 255, 0, 0);
graphics_update();
}
camera_close();
graphics_close();
return 0;
}