Function onScreenWidth

pj_scene2D/core/tests/overlay_geometry_test.cpp:53–55

effective_scale = on-screen pixels per image pixel; the renderer's view transform multiplies geometry by this, so on-screen width = image extent × effective_scale. image_px_per_screen_px is its reciprocal.

// transform multiplies geometry by this, so on-screen width = image extent ×
// effective_scale. image_px_per_screen_px is its reciprocal.
double onScreenWidth(const std::vector<float>& geom, int axis, double effective_scale) {
  return extent(geom, axis) * effective_scale;
}

double strokeOnScreenWidth(double thickness, double effective_scale) {
  std::vector<float> geom;