rescalc: improve reflection boundary conditions

Make parameter names more clear/consistent, document them, implement
missing 1U boundary.

1 files changed, 8 insertions, 1 deletions

diff --git a/residual_calc.h b/residual_calc.h
index 8c9b628..1498bc9 100644
--- a/residual_calc.h
+++ b/residual_calc.h
@@ -67,6 +67,12 @@ int mg2di_residual_calc_init(ResidualCalcContext *ctx);
 
 /**
  * Calculate the residual.
+ *
+ * @param reflect Flags indicating if dst should be extended by reflection.
+ *      If the 'MG2D_BOUNDARY_x'th bit is set in reflect, then dst should be
+ *      reflected reflect_dist points beyond its bounds in the corresponding
+ *      direction.
+ * @param reflect_dist number of points to fill by reflection
  */
 int mg2di_residual_calc(ResidualCalcContext *ctx, size_t size[2],
                         double      *residual_max,
@@ -75,6 +81,7 @@ int mg2di_residual_calc(ResidualCalcContext *ctx, size_t size[2],
                         const double         *rhs, ptrdiff_t rhs_stride,
                         const double * const diff_coeffs[MG2D_DIFF_COEFF_NB],
                         ptrdiff_t diff_coeffs_stride,
-                        double u_mult, double res_mult, int mirror_line);
+                        double u_mult, double res_mult,
+                        int reflect, size_t reflect_dist);
 
 #endif // MG2D_RESIDUAL_CALC_H