added unprojection into homogenous space for matrices

src/core/include/pw/core/matrix.hpp

@@ -23,6 +23,7 @@
 #ifndef PW_CORE_MATRIX_HPP
 #define PW_CORE_MATRIX_HPP
 
+#include "vector.hpp"
 #include <pw/core/globals.hpp>
 #include <pw/core/math.hpp>
 #include <pw/core/vector.hpp>
@@ -205,6 +206,15 @@ struct matrix final {
         }(std::make_index_sequence<RowsSlice>{}); // rowwise expansion
     }
 
+    constexpr auto unproject(const Scalar& w) const noexcept
+        -> matrix<Scalar, Rows + 1, Cols + 1> {
+        return [&w, this]<std::size_t... Rs>(std::index_sequence<Rs...>) {
+            return matrix<Scalar, Rows + 1, Cols + 1>{
+                (Rs < Rows) ? (*this)[Rs].unproject(0)
+                            : vector<Scalar, Cols + 1>::basis(Cols) * w...};
+        }(std::make_index_sequence<Rows + 1>{}); // rowwise expansion
+    }
+
     //
     // Iterators
     //

src/core/include/pw/core/point.hpp

@@ -24,20 +24,11 @@
 #define PW_CORE_POINT_HPP
 
 #include <pw/core/globals.hpp>
+#include <pw/core/vector.hpp>
 
 namespace pw {
 
-template <typename Scalar> struct point final {
-
-    using value_type = Scalar;
-
-    Scalar x{}, y{};
-
-    template <typename ScalarOut>
-    constexpr auto cast() const noexcept -> point<ScalarOut> {
-        return {.x{ScalarOut(x)}, .y{ScalarOut(y)}};
-    }
-};
+template <typename Scalar> using point = vector<Scalar, 2>;
 
 } // namespace pw
 

src/core/tests/pwcore_test_matrix.cpp

@@ -65,4 +65,9 @@ auto main() -> int {
 
     // octave/matlab style output
     std::print("\nm33=[{}]\n", m33);
+
+    auto m44 = m33.unproject(1);
+
+    std::print("\nm44=[{}]\n", m44);
+
 }