New dmnsn_radians() and dmnsn_degrees() conversion functions.

4 files changed, 26 insertions, 16 deletions

diff --git a/dimension/parse.c b/dimension/parse.c
index fc067cf..7b33b1d 100644
--- a/dimension/parse.c
+++ b/dimension/parse.c
@@ -564,7 +564,7 @@ dmnsn_eval_zeroary(dmnsn_astnode astnode, dmnsn_symbol_table *symtable)
 
   switch (astnode.type) {
   case DMNSN_AST_PI:
-    dmnsn_make_ast_float(&ret, 4*atan(1.0));
+    dmnsn_make_ast_float(&ret, M_PI);
     break;
   case DMNSN_AST_TRUE:
     dmnsn_make_ast_integer(&ret, 1);
@@ -736,7 +736,7 @@ dmnsn_eval_unary(dmnsn_astnode astnode, dmnsn_symbol_table *symtable)
       dmnsn_make_ast_float(&ret, cosh(n));
       break;
     case DMNSN_AST_DEGREES:
-      dmnsn_make_ast_float(&ret, n*45.0/atan(1.0));
+      dmnsn_make_ast_float(&ret, dmnsn_degrees(n));
       break;
     case DMNSN_AST_EXP:
       dmnsn_make_ast_float(&ret, exp(n));
@@ -754,7 +754,7 @@ dmnsn_eval_unary(dmnsn_astnode astnode, dmnsn_symbol_table *symtable)
       dmnsn_make_ast_float(&ret, log(n)/log(10.0));
       break;
     case DMNSN_AST_RADIANS:
-      dmnsn_make_ast_float(&ret, n*atan(1.0)/45.0);
+      dmnsn_make_ast_float(&ret, dmnsn_radians(n));
       break;
     case DMNSN_AST_SIN:
       dmnsn_make_ast_float(&ret, sin(n));
@@ -840,7 +840,7 @@ dmnsn_eval_unary(dmnsn_astnode astnode, dmnsn_symbol_table *symtable)
       dmnsn_make_ast_float(&ret, cosh(n));
       break;
     case DMNSN_AST_DEGREES:
-      dmnsn_make_ast_float(&ret, n*45.0/atan(1.0));
+      dmnsn_make_ast_float(&ret, dmnsn_degrees(n));
       break;
     case DMNSN_AST_EXP:
       dmnsn_make_ast_float(&ret, exp(n));
@@ -858,7 +858,7 @@ dmnsn_eval_unary(dmnsn_astnode astnode, dmnsn_symbol_table *symtable)
       dmnsn_make_ast_float(&ret, log(n)/log(10.0));
       break;
     case DMNSN_AST_RADIANS:
-      dmnsn_make_ast_float(&ret, n*atan(1.0)/45.0);
+      dmnsn_make_ast_float(&ret, dmnsn_radians(n));
       break;
     case DMNSN_AST_SIN:
       dmnsn_make_ast_float(&ret, sin(n));
@@ -1141,7 +1141,7 @@ dmnsn_eval_binary(dmnsn_astnode astnode, dmnsn_symbol_table *symtable)
           az.type == DMNSN_AST_INTEGER ? *(long *)az.ptr : *(double *)az.ptr
         );
 
-        axis = dmnsn_vector_mul(atan(1.0)/45.0, axis);
+        axis = dmnsn_vector_mul(dmnsn_radians(1.0), axis);
         r = dmnsn_transform_vector(dmnsn_rotation_matrix(axis), r);
 
         ret = dmnsn_copy_astnode(astnode);
@@ -1247,7 +1247,7 @@ dmnsn_eval_binary(dmnsn_astnode astnode, dmnsn_symbol_table *symtable)
           az.type == DMNSN_AST_INTEGER ? *(long *)az.ptr : *(double *)az.ptr
         );
 
-        axis = dmnsn_vector_mul(atan(1.0)/45.0, axis);
+        axis = dmnsn_vector_mul(dmnsn_radians(1.0), axis);
 
         r = dmnsn_transform_vector(
           dmnsn_rotation_matrix(dmnsn_new_vector(axis.x, 0.0, 0.0)),
diff --git a/dimension/realize.c b/dimension/realize.c
index 563327c..967c5db 100644
--- a/dimension/realize.c
+++ b/dimension/realize.c
@@ -142,13 +142,11 @@ dmnsn_realize_rotation(dmnsn_astnode astnode)
 {
   dmnsn_assert(astnode.type == DMNSN_AST_ROTATION, "Expected a rotation.");
 
-  const double deg2rad = atan(1.0)/45.0;
-
   dmnsn_astnode angle_node;
   dmnsn_array_get(astnode.children, 0, &angle_node);
 
   dmnsn_vector angle = dmnsn_vector_mul(
-    deg2rad,
+    dmnsn_radians(1.0),
     dmnsn_realize_vector(angle_node)
   );
 
@@ -266,8 +264,6 @@ dmnsn_realize_camera(dmnsn_astnode astnode)
 {
   dmnsn_assert(astnode.type == DMNSN_AST_CAMERA, "Expected a camera.");
 
-  const double deg2rad = atan(1.0)/45.0;
-
   dmnsn_astnode_type camera_type = DMNSN_AST_PERSPECTIVE;
   dmnsn_vector location  = dmnsn_new_vector(0.0, 0.0, 0.0);
   dmnsn_vector direction = dmnsn_new_vector(0.0, 0.0, 1.0);
@@ -363,7 +359,7 @@ dmnsn_realize_camera(dmnsn_astnode astnode)
     case DMNSN_AST_ANGLE:
       {
         dmnsn_array_get(item->children, 0, &child);
-        double angle = deg2rad*dmnsn_realize_float(child);
+        double angle = dmnsn_radians(dmnsn_realize_float(child));
         direction = dmnsn_vector_mul(
           0.5*dmnsn_vector_norm(right)/tan(angle/2.0),
           dmnsn_vector_normalize(direction)
diff --git a/libdimension/dimension/geometry.h b/libdimension/dimension/geometry.h
index d55126d..c9f036f 100644
--- a/libdimension/dimension/geometry.h
+++ b/libdimension/dimension/geometry.h
@@ -70,7 +70,7 @@ static const dmnsn_vector dmnsn_x    = { 1.0, 0.0, 0.0 };
 static const dmnsn_vector dmnsn_y    = { 0.0, 1.0, 0.0 };
 static const dmnsn_vector dmnsn_z    = { 0.0, 0.0, 1.0 };
 
-/* Min/max macros */
+/* Scalar functions */
 
 DMNSN_INLINE double
 dmnsn_min(double a, double b)
@@ -84,6 +84,18 @@ dmnsn_max(double a, double b)
   return a > b ? a : b;
 }
 
+DMNSN_INLINE double
+dmnsn_radians(double degrees)
+{
+  return degrees*M_PI/180.0;
+}
+
+DMNSN_INLINE double
+dmnsn_degrees(double radians)
+{
+  return radians*180.0/M_PI;
+}
+
 /* Shorthand for vector/matrix construction */
 
 DMNSN_INLINE dmnsn_vector
diff --git a/tests/libdimension/tests.c b/tests/libdimension/tests.c
index 68fac12..393a1d6 100644
--- a/tests/libdimension/tests.c
+++ b/tests/libdimension/tests.c
@@ -57,7 +57,7 @@ dmnsn_new_default_scene()
     trans
   );
   trans = dmnsn_matrix_mul(
-    dmnsn_rotation_matrix(dmnsn_new_vector(0.0, 1.0, 0.0)),
+    dmnsn_rotation_matrix(dmnsn_new_vector(0.0, dmnsn_radians(53.0), 0.0)),
     trans
   );
 
@@ -86,7 +86,9 @@ dmnsn_new_default_scene()
   cube->interior = dmnsn_new_interior();
   cube->interior->ior = 1.1;
 
-  cube->trans = dmnsn_rotation_matrix(dmnsn_new_vector(0.75, 0.0, 0.0));
+  cube->trans = dmnsn_rotation_matrix(
+    dmnsn_new_vector(dmnsn_radians(45.0), 0.0, 0.0)
+  );
 
   dmnsn_object *csg = dmnsn_new_csg_difference(cube, sphere);
   dmnsn_array_push(scene->objects, &csg);