diff options
| -rw-r--r-- | viewport.h | 14 |
1 files changed, 12 insertions, 2 deletions
@@ -59,6 +59,12 @@ class basic_viewport { // double focus_length; // distance between the focus point and the image screen hitlist &world; vec3<V> vup{0, 1, 0}; // vector determine the camera rotating + + inline void check_vup() const { + // vup must not be parallel with screen_center-cxyz + assert(!vup.parallel(screen_center - cxyz)); + } + public: basic_viewport(const vec3<V> &cxyz, const vec3<V> &screen_center, @@ -67,7 +73,9 @@ public: cxyz{cxyz}, screen_center{screen_center}, image_width{image_width}, image_height{image_height}, screen_hw{(cxyz - screen_center).norm() * tan((double) fov_h / 2.0)}, screen_hh{screen_hw * ((double) image_height / image_width)}, - world{world} {} + world{world} { + check_vup(); + } basic_viewport(const vec3<V> &cxyz, const vec3<V> &screen_center, uint32_t image_width, uint32_t image_height, @@ -78,6 +86,7 @@ public: screen_hh{screen_hh}, world{world} { assert(std::abs(1.0 * image_width / image_height - 1.0 * screen_hw / screen_hh) < 1e-8); + check_vup(); } /** @@ -98,8 +107,9 @@ public: // screen plane is determined by coord system x`Vy`, where V is screen_center // for variable name we let u := x`, v := y` const auto u = cross(r, vup).unit_vec() * screen_hw, v = cross(u, r).unit_vec() * screen_hh; + assert(dot(r, u) < 1e-8); + assert(dot(r, v) < 1e-8); assert(dot(u, v) < 1e-8); - assert(dot(u, r) < 1e-8); // iterate over every pixel on the image for (int j = -img_hh; j < img_hh; ++j) { // axis y, transformation is needed for (int i = -img_hw; i < img_hw; ++i) { // axis x |