Trying to switch to more object-oriented

sdlpp/sdlpp_geometry_line.hpp

@@ -0,0 +1,30 @@
+#ifndef SDLPP_HPP_GEOMETRY_LINE
+#define SDLPP_HPP_GEOMETRY_LINE
+
+#include "sdlpp_common.hpp"
+#include "sdlpp_vector.hpp"
+#include "sdlpp_line.hpp"
+#include <algorithm>
+
+namespace SDLPP {
+template<typename T>
+Vec2D<T> pointProjectionOnLine( const Vec2D<T> &point, const Line<T> &line ) {
+    /* from here -
+     * https://stackoverflow.com/questions/849211/shortest-distance-between-a-point-and-a-line-segment
+     */
+    auto length_squared = line.lengthSquared();
+    if ( length_squared == 0.0 )
+        return point;
+    auto t =
+        std::max( 0.0, std::min( 1.0, ( ( point - line.getStart() ) *
+                                        ( line.getEnd() - line.getStart() ) ) /
+                                          length_squared ) );
+    return line.getStart() + t * ( line.getEnd() - line.getStart() );
+}
+template<typename T>
+double pointLineDistance( const Vec2D<T> &point, const Line<T> &line ) {
+    return vecDistance( point, pointProjectionOnLine( point, line ) );
+}
+} // namespace SDLPP
+
+#endif