Add cylinder support to dimension.

9 files changed, 97 insertions, 2 deletions

diff --git a/dimension/common.nonterminals b/dimension/common.nonterminals
index 5f915c5..09a4f5f 100644
--- a/dimension/common.nonterminals
+++ b/dimension/common.nonterminals
@@ -40,6 +40,8 @@
 %type <astnode> OBJECT
 %type <astnode> FINITE_SOLID_OBJECT
 %type <astnode> BOX
+%type <astnode> CYLINDER
+%type <astnode> MAYBE_OPEN
 %type <astnode> SPHERE
 %type <astnode> INFINITE_SOLID_OBJECT
 %type <astnode> PLANE
diff --git a/dimension/common.rules b/dimension/common.rules
index 89b7ab8..e5e6543 100644
--- a/dimension/common.rules
+++ b/dimension/common.rules
@@ -283,6 +283,7 @@ OBJECT: FINITE_SOLID_OBJECT
 ;
 
 FINITE_SOLID_OBJECT: BOX
+                   | CYLINDER
                    | SPHERE
 ;
 
@@ -296,6 +297,25 @@ BOX: "box" "{"
    }
 ;
 
+CYLINDER: "cylinder" "{"
+            VECTOR "," VECTOR "," FLOAT
+            MAYBE_OPEN
+            OBJECT_MODIFIERS
+          "}"
+        {
+          dmnsn_astnode object
+            = dmnsn_new_astnode4(DMNSN_AST_CYLINDER, @$, $3, $5, $7, $8);
+          $$ = dmnsn_new_astnode2(DMNSN_AST_OBJECT, @$, object, $9);
+        }
+;
+
+MAYBE_OPEN: /* empty */ {
+            $$ = dmnsn_new_ast_integer(false);
+          }
+          | "open" {
+            $$ = dmnsn_new_ast_integer(true);
+          }
+
 SPHERE: "sphere" "{"
           VECTOR "," FLOAT
           OBJECT_MODIFIERS
diff --git a/dimension/common.terminals b/dimension/common.terminals
index 7ccc8cb..af75bb4 100644
--- a/dimension/common.terminals
+++ b/dimension/common.terminals
@@ -152,7 +152,7 @@
 %token DMNSN_T_CUBIC_SPLINE
 %token DMNSN_T_CUBIC_WAVE
 %token DMNSN_T_CUTAWAY_TEXTURES
-%token DMNSN_T_CYLINDER
+%token DMNSN_T_CYLINDER                 "cylinder"
 %token DMNSN_T_CYLINDRICAL
 %token DMNSN_T_DEFINED
 %token DMNSN_T_DEGREES                  "degrees"
@@ -315,7 +315,7 @@
 %token DMNSN_T_ON                       "on"
 %token DMNSN_T_ONCE
 %token DMNSN_T_ONION
-%token DMNSN_T_OPEN
+%token DMNSN_T_OPEN                     "open"
 %token DMNSN_T_ORIENT
 %token DMNSN_T_ORIENTATION
 %token DMNSN_T_ORTHOGRAPHIC
diff --git a/dimension/grammar.epilogue b/dimension/grammar.epilogue
index 25d678a..d766a07 100644
--- a/dimension/grammar.epilogue
+++ b/dimension/grammar.epilogue
@@ -134,6 +134,7 @@ dmnsn_astnode_string(dmnsn_astnode_type astnode_type)
 
   dmnsn_astnode_map(DMNSN_AST_OBJECT,       "object");
   dmnsn_astnode_map(DMNSN_AST_BOX,          "box");
+  dmnsn_astnode_map(DMNSN_AST_CYLINDER,     "cylinder");
   dmnsn_astnode_map(DMNSN_AST_DIFFERENCE,   "difference");
   dmnsn_astnode_map(DMNSN_AST_INTERSECTION, "intersection");
   dmnsn_astnode_map(DMNSN_AST_LIGHT_SOURCE, "light_source");
diff --git a/dimension/lexer.l b/dimension/lexer.l
index ea98c07..190acb0 100644
--- a/dimension/lexer.l
+++ b/dimension/lexer.l
@@ -186,6 +186,7 @@ unsigned long wchar;
 "colour"                RETURN_TOKEN(DMNSN_T_COLOR);
 "cos"                   RETURN_TOKEN(DMNSN_T_COS);
 "cosh"                  RETURN_TOKEN(DMNSN_T_COSH);
+"cylinder"              RETURN_TOKEN(DMNSN_T_CYLINDER);
 "degrees"               RETURN_TOKEN(DMNSN_T_DEGREES);
 "difference"            RETURN_TOKEN(DMNSN_T_DIFFERENCE);
 "diffuse"               RETURN_TOKEN(DMNSN_T_DIFFUSE);
@@ -224,6 +225,7 @@ unsigned long wchar;
 "object"                RETURN_TOKEN(DMNSN_T_OBJECT);
 "off"                   RETURN_TOKEN(DMNSN_T_OFF);
 "on"                    RETURN_TOKEN(DMNSN_T_ON);
+"open"                  RETURN_TOKEN(DMNSN_T_OPEN);
 "perspective"           RETURN_TOKEN(DMNSN_T_PERSPECTIVE);
 "phong"                 RETURN_TOKEN(DMNSN_T_PHONG);
 "phong_size"            RETURN_TOKEN(DMNSN_T_PHONG_SIZE);
diff --git a/dimension/parse.h b/dimension/parse.h
index e81f76e..d9b9195 100644
--- a/dimension/parse.h
+++ b/dimension/parse.h
@@ -48,6 +48,7 @@ typedef enum {
 
   DMNSN_AST_OBJECT,
   DMNSN_AST_BOX,
+  DMNSN_AST_CYLINDER,
   DMNSN_AST_DIFFERENCE,
   DMNSN_AST_INTERSECTION,
   DMNSN_AST_LIGHT_SOURCE,
diff --git a/dimension/realize.c b/dimension/realize.c
index ad6630f..15eb334 100644
--- a/dimension/realize.c
+++ b/dimension/realize.c
@@ -843,6 +843,50 @@ dmnsn_realize_box(dmnsn_astnode astnode)
 }
 
 static dmnsn_object *
+dmnsn_realize_cylinder(dmnsn_astnode astnode)
+{
+  dmnsn_assert(astnode.type == DMNSN_AST_CYLINDER, "Expected a cylinder.");
+
+  dmnsn_astnode pnode1, pnode2, radius, open;
+  dmnsn_array_get(astnode.children, 0, &pnode1);
+  dmnsn_array_get(astnode.children, 1, &pnode2);
+  dmnsn_array_get(astnode.children, 2, &radius);
+  dmnsn_array_get(astnode.children, 3, &open);
+
+  dmnsn_vector p1 = dmnsn_realize_vector(pnode1);
+  dmnsn_vector p2 = dmnsn_realize_vector(pnode2);
+  double r = dmnsn_realize_float(radius);
+
+  dmnsn_vector dir = dmnsn_vector_sub(p2, p1);
+  double l = dmnsn_vector_norm(dir);
+
+  double theta1 = dmnsn_vector_axis_angle(dmnsn_y, dir, dmnsn_x);
+  double theta2 = dmnsn_vector_axis_angle(dmnsn_y, dir, dmnsn_z);
+
+  dmnsn_object *cylinder = dmnsn_new_cylinder(dmnsn_realize_integer(open));
+  /* Transformations: lift the cylinder to start at the origin, scale, rotate,
+     and translate properly */
+  cylinder->trans = dmnsn_translation_matrix(dmnsn_new_vector(0.0, 1.0, 0.0));
+  cylinder->trans = dmnsn_matrix_mul(
+    dmnsn_scale_matrix(dmnsn_new_vector(r, l/2.0, r)),
+    cylinder->trans
+  );
+  cylinder->trans = dmnsn_matrix_mul(
+    dmnsn_rotation_matrix(dmnsn_new_vector(theta1, 0.0, 0.0)),
+    cylinder->trans
+  );
+  cylinder->trans = dmnsn_matrix_mul(
+    dmnsn_rotation_matrix(dmnsn_new_vector(0.0, 0.0, theta2)),
+    cylinder->trans
+  );
+  cylinder->trans = dmnsn_matrix_mul(
+    dmnsn_translation_matrix(p1),
+    cylinder->trans
+  );
+  return cylinder;
+}
+
+static dmnsn_object *
 dmnsn_realize_sphere(dmnsn_astnode astnode)
 {
   dmnsn_assert(astnode.type == DMNSN_AST_SPHERE, "Expected a sphere.");
@@ -989,6 +1033,9 @@ dmnsn_realize_object(dmnsn_astnode astnode, dmnsn_array *lights)
   case DMNSN_AST_BOX:
     object = dmnsn_realize_box(onode);
     break;
+  case DMNSN_AST_CYLINDER:
+    object = dmnsn_realize_cylinder(onode);
+    break;
   case DMNSN_AST_DIFFERENCE:
     object = dmnsn_realize_difference(onode, modifiers, lights);
     break;
diff --git a/tests/dimension/demo.pov b/tests/dimension/demo.pov
index 4e8ba4d..69c9d4e 100644
--- a/tests/dimension/demo.pov
+++ b/tests/dimension/demo.pov
@@ -71,6 +71,14 @@ difference {
   }
 }
 
+cylinder {
+  -1.25*y, 1.25*y, 0.1
+  pigment {
+    color rgb <1, 0, 0>
+  }
+  rotate -45*x
+}
+
 plane {
   y, -2
   pigment {
diff --git a/tests/dimension/demo.sh b/tests/dimension/demo.sh
index a5f05a5..2bf21b9 100755
--- a/tests/dimension/demo.sh
+++ b/tests/dimension/demo.sh
@@ -77,6 +77,20 @@ demo_exp=$(echo -n \
               (phong_size (float 40)))))))
       object-modifiers)
   (object
+    (cylinder
+      (vector (float 0) (float -1.25) (float 0) (float 0) (float 0))
+      (vector (float 0) (float 1.25) (float 0) (float 0) (float 0))
+      (float 0.1)
+      (integer 0))
+    (object-modifiers
+      (pigment
+        (vector (integer 1) (integer 0) (integer 0)
+                (integer 0) (integer 0))
+        pigment-modifiers)
+      (transformation
+        (rotation (vector (integer -45) (integer 0) (integer 0)
+                          (integer 0) (integer 0))))))
+  (object
     (plane
       (vector (integer 0) (integer 1) (integer 0) (integer 0) (integer 0))
       (integer -2))