void x3ds_definition::ensure_camera()
{
if (m_file->cameras == NULL)
{
// Fabricate camera
Lib3dsCamera* camera = lib3ds_camera_new("Perscpective");
float size;
Lib3dsVector bmin, bmax;
get_bounding_center(bmin, bmax, camera->target, &size);
memcpy(camera->position, camera->target, sizeof(camera->position));
camera->position[0] = bmax[0] + 0.75f * size;
camera->position[1] = bmin[1] - 0.75f * size;
camera->position[2] = bmax[2] + 0.75f * size;
// hack
Lib3dsMatrix m;
lib3ds_matrix_identity(m);
lib3ds_matrix_rotate_z(m, 1.6f); // PI/2
lib3ds_matrix_rotate_y(m, 0.3f);
lib3ds_vector_transform(camera->position, m, camera->position);
camera->near_range = (camera->position[0] - bmax[0] ) * 0.5f;
camera->far_range = (camera->position[0] - bmin[0] ) * 3.0f;
lib3ds_file_insert_camera(m_file, camera);
}
}
/*!
* \ingroup matrix
*/
void
lib3ds_matrix_camera(Lib3dsMatrix matrix, Lib3dsVector pos,
Lib3dsVector tgt, Lib3dsFloat roll)
{
Lib3dsMatrix M,R;
Lib3dsVector x, y, z;
lib3ds_vector_sub(y, tgt, pos);
lib3ds_vector_normalize(y);
z[0] = 0;
z[1] = 0;
z[2] = 1.0;
lib3ds_vector_cross(x, y, z);
lib3ds_vector_cross(z, x, y);
lib3ds_vector_normalize(x);
lib3ds_vector_normalize(y);
lib3ds_matrix_identity(M);
M[0][0] = x[0];
M[1][0] = x[1];
M[2][0] = x[2];
M[0][1] = y[0];
M[1][1] = y[1];
M[2][1] = y[2];
M[0][2] = z[0];
M[1][2] = z[1];
M[2][2] = z[2];
lib3ds_matrix_identity(R);
lib3ds_matrix_rotate_y(R, roll);
lib3ds_matrix_mul(matrix, R,M);
lib3ds_matrix_translate_xyz(matrix, -pos[0],-pos[1],-pos[2]);
}
/*!
* Compute a camera matrix based on position, target and roll.
*
* Generates a translate/rotate matrix that maps world coordinates
* to camera coordinates. Resulting matrix does not include perspective
* transform.
*
* \param matrix Destination matrix.
* \param pos Camera position
* \param tgt Camera target
* \param roll Roll angle
*
* \ingroup matrix
*/
void
lib3ds_matrix_camera(Lib3dsMatrix matrix, Lib3dsVector pos,
Lib3dsVector tgt, Lib3dsFloat roll)
{
Lib3dsMatrix M;
Lib3dsVector x, y, z;
lib3ds_vector_sub(y, tgt, pos);
lib3ds_vector_normalize(y);
if (y[0] != 0. || y[1] != 0) {
z[0] = 0;
z[1] = 0;
z[2] = 1.0;
}
else { /* Special case: looking straight up or down z axis */
z[0] = -1.0;
z[1] = 0;
z[2] = 0;
}
lib3ds_vector_cross(x, y, z);
lib3ds_vector_cross(z, x, y);
lib3ds_vector_normalize(x);
lib3ds_vector_normalize(z);
lib3ds_matrix_identity(M);
M[0][0] = x[0];
M[1][0] = x[1];
M[2][0] = x[2];
M[0][1] = y[0];
M[1][1] = y[1];
M[2][1] = y[2];
M[0][2] = z[0];
M[1][2] = z[1];
M[2][2] = z[2];
lib3ds_matrix_identity(matrix);
lib3ds_matrix_rotate_y(matrix, roll);
lib3ds_matrix_mult(matrix, M);
lib3ds_matrix_translate_xyz(matrix, -pos[0],-pos[1],-pos[2]);
}
