Files
lace/3-mid/opengl/source/lean/geometry/opengl-geometry.adb
2023-05-31 11:39:01 +10:00

545 lines
14 KiB
Ada

with
openGL.Primitive.indexed,
openGL.Primitive.long_indexed,
ada.unchecked_Deallocation;
package body openGL.Geometry
is
---------
-- Forge
--
procedure destroy (Self : in out Item)
is
use openGL.Buffer;
begin
free (Self.Vertices);
Self.free_Primitives;
end destroy;
procedure free (Self : in out View)
is
procedure deallocate is new ada.unchecked_Deallocation (Item'Class, View);
begin
if Self = null then
return;
end if;
Self.destroy;
deallocate (Self);
end free;
procedure free_Primitives (Self : in out Item)
is
begin
for Each in 1 .. Self.primitive_Count
loop
Primitive.free (Self.Primitives (Each));
end loop;
Self.primitive_Count := 0;
end free_Primitives;
--------------
-- Attributes
--
procedure Model_is (Self : in out Item; Now : in Model_view)
is
begin
Self.Model := Now;
end Model_is;
function Label (Self : in Item'Class) return String
is
begin
return to_String (Self.Label);
end Label;
procedure Label_is (Self : in out Item'Class; Now : in String)
is
begin
overwrite (Self.Label, 1, Now);
end Label_is;
procedure Indices_are (Self : in out Item; Now : in Indices;
for_Facia : in Positive)
is
the_Primitive : constant Primitive.indexed.view
:= Primitive.indexed.view (Self.Primitives (Index_t (for_Facia)));
begin
the_Primitive.Indices_are (Now);
end Indices_are;
procedure Indices_are (Self : in out Item; Now : in long_Indices;
for_Facia : in Positive)
is
the_Primitive : constant Primitive.long_indexed.view
:= Primitive.long_indexed.view (Self.Primitives (Index_t (for_Facia)));
begin
the_Primitive.Indices_are (Now);
end Indices_are;
function Primitives (Self : in Item'Class) return Primitive.views
is
begin
return Self.Primitives (1 .. Self.primitive_Count);
end Primitives;
function Fade (Self : in Item; Which : texture_Set.texture_ID := 1) return texture_Set.fade_Level
is
begin
raise program_Error with "Geometry has no texture.";
return texture_Set.fade_Level'Last;
end Fade;
-- function Texture (Self : in Item) return openGL.Texture.Object
-- is
-- begin
-- raise program_Error with "Geometry has no texture.";
-- return openGL.Texture.null_Object;
-- end Texture;
function Texture (Self : in Item; Which : in texture_Set.texture_ID := 1) return openGL.Texture.Object
is
begin
raise program_Error with "Geometry has no texture.";
return openGL.Texture.null_Object;
end Texture;
procedure Program_is (Self : in out Item; Now : in openGL.Program.view)
is
begin
Self.Program := Now;
end Program_is;
function Program (Self : in Item) return openGL.Program.view
is
begin
return Self.Program;
end Program;
function Bounds (self : in Item'Class) return openGL.Bounds
is
begin
return Self.Bounds;
end Bounds;
procedure Bounds_are (Self : in out Item'Class; Now : in openGL.Bounds)
is
begin
Self.Bounds := Now;
end Bounds_are;
function is_Transparent (Self : in Item) return Boolean
is
begin
return Self.is_Transparent;
-- or Self.Textures.Textures (1).Object.is_Transparent
-- or Self.Textures.Textures (2).Object.is_Transparent; -- TODO: Loop over all textures.
-- -- return Self.is_Transparent
-- -- or Self.Texture_1.is_Transparent
-- -- or Self.Texture_2.is_Transparent;
end is_Transparent;
procedure is_Transparent (Self : in out Item; Now : in Boolean := True)
is
begin
Self.is_Transparent := Now;
end is_Transparent;
--------------
-- Operations
--
procedure add (Self : in out Item'Class; the_Primitive : in Primitive.view)
is
begin
Self.primitive_Count := Self.primitive_Count + 1;
Self.Primitives (self.primitive_Count) := the_Primitive;
end add;
procedure render (Self : in out Item'Class)
is
begin
if Self.primitive_Count = 0
then
raise Error with "Unable to render geometry with no primitives.";
end if;
Self .enable_Textures;
Self.Program .set_Uniforms;
Self.Vertices.enable;
Self.Program .enable_Attributes;
for Each in 1 .. self.primitive_Count -- Render each primitive.
loop
Self.Primitives (Each).render;
end loop;
end render;
-----------
-- Normals
--
generic
type any_Index_t is range <>;
type any_Indices is array (long_Index_t range <>) of any_Index_t;
function any_vertex_Id_in (face_Kind : in primitive.facet_Kind;
Indices : in any_Indices;
for_Facet : in long_Index_t;
for_Point : in long_Index_t) return any_Index_t;
function any_vertex_Id_in (face_Kind : in Primitive.facet_Kind;
Indices : in any_Indices;
for_Facet : in long_Index_t;
for_Point : in long_Index_t) return any_Index_t
is
use openGL.Primitive;
begin
case face_Kind
is
when Triangles =>
return Indices (3 * (for_Facet - 1) + for_Point);
when triangle_Strip =>
return Indices (for_Facet - 1 + for_Point);
when triangle_Fan =>
if for_Point = 1
then return 1;
else return Indices (for_Facet - 1 + for_Point);
end if;
when others =>
raise Error with "openGL primitive " & face_Kind'Image & " not yet supported.";
end case;
end any_vertex_Id_in;
generic
type any_Index_t is range <>;
type any_Indices is array (long_Index_t range <>) of any_Index_t;
function any_facet_Count_in (face_Kind : in primitive.facet_Kind;
Indices : in any_Indices) return long_Index_t;
--
-- Returns the maximum possible facet count, which includes redundant facets.
function any_facet_Count_in (face_Kind : in primitive.facet_Kind;
Indices : in any_Indices) return long_Index_t
is
use Primitive;
begin
case face_Kind
is
when Triangles =>
return Indices'Length / 3;
when triangle_Strip
| triangle_Fan =>
return Indices'Length - 2;
when others =>
raise Error with "openGL primitive " & face_Kind'Image & " not yet supported.";
end case;
end any_facet_Count_in;
function facet_Count_in is new any_facet_Count_in (any_Index_t => Index_t,
any_Indices => Indices);
pragma Unreferenced (facet_Count_in);
----------
-- Facets
--
type Facet is array ( Index_t range 1 .. 3) of Index_t; -- An 'indexed' triangle.
type Facets is array (long_Index_t range <> ) of Facet;
type Facets_view is access all Facets;
procedure free is new ada.unchecked_Deallocation (Facets, Facets_view);
generic
type any_Index_t is range <>;
type any_Indices is array (long_Index_t range <>) of any_Index_t;
function any_Facets_of (face_Kind : in primitive.facet_Kind;
Indices : in any_Indices) return access Facets;
--
-- 'Facets_of' returns all non-redundant facets.
function any_Facets_of (face_Kind : in primitive.facet_Kind;
Indices : in any_Indices) return access Facets
is
use openGL.Primitive;
function facet_Count_in is new any_facet_Count_in (any_Index_t => any_Index_t,
any_Indices => any_Indices);
function vertex_Id_in is new any_vertex_Id_in (any_Index_t => any_Index_t,
any_Indices => any_Indices);
the_Facets : Facets_view := new Facets (1 .. facet_Count_in (face_Kind, Indices));
Count : long_Index_t := 0;
begin
for Each in the_Facets'Range
loop
declare
P1 : constant Index_t := Index_t (vertex_Id_in (face_Kind, Indices, Each, 1));
P2 : constant Index_t := Index_t (vertex_Id_in (face_Kind, Indices, Each, 2));
P3 : constant Index_t := Index_t (vertex_Id_in (face_Kind, Indices, Each, 3));
begin
if not ( P1 = P2
or P1 = P3
or P2 = P3)
then
Count := Count + 1;
case face_Kind
is
when Triangles
| triangle_Fan =>
the_Facets (Count) := [P1, P2, P3];
when triangle_Strip =>
if Each mod 2 = 0
then -- Is an even facet.
the_Facets (Count) := [P1, P3, P2];
else
the_Facets (Count) := [P1, P2, P3];
end if;
when others =>
raise Error with "openGL primitive " & face_Kind'Image & " not yet supported.";
end case;
end if;
end;
end loop;
declare
Result : constant Facets_view := new Facets' (the_Facets (1 .. Count));
begin
free (the_Facets);
return Result;
end;
end any_Facets_of;
function Facets_of is new any_Facets_of (Index_t,
Indices);
pragma Unreferenced (Facets_of);
-----------
-- Normals
--
type Normals_view is access Normals;
generic
type any_Index_t is range <>;
type any_Indices is array (long_Index_t range <>) of any_Index_t;
function any_Normals_of (face_Kind : in primitive.facet_Kind;
Indices : in any_Indices;
Sites : in openGL.Sites) return access Normals;
function any_Normals_of (face_Kind : in primitive.facet_Kind;
Indices : in any_Indices;
Sites : in openGL.Sites) return access Normals
is
function Facets_of is new any_Facets_of (any_Index_t,
any_Indices);
the_Normals : constant Normals_view := new Normals (Sites'Range);
the_Facets : Facets_view := Facets_of (face_Kind,
Indices).all'unchecked_Access;
type facet_Normals is array (long_Index_t range 1 .. the_Facets'Length) of Normal;
type facet_Normals_view is access all facet_Normals;
procedure free is new ada.unchecked_Deallocation (facet_Normals, facet_Normals_view); -- TODO: Should not be needed since freeing will occur when 'facet_Normals_view' goes out of scope ?
the_facet_Normals : facet_Normals_view := new facet_Normals;
N : Vector_3;
length_N : Real;
begin
-- Calculate normal at each facet.
--
for Each in the_Facets'Range
loop
N := (Sites (the_Facets (Each)(2)) - Sites (the_Facets (Each)(1)))
* (Sites (the_Facets (Each)(3)) - Sites (the_Facets (Each)(1)));
length_N := abs (N);
if almost_Zero (length_N)
then the_facet_Normals (Each) := N; -- 0 vector !
else the_facet_Normals (Each) := (1.0 / length_N) * N;
end if;
end loop;
-- Calculate normal at each vertex.
--
declare
Id : Index_t;
Length : Real;
begin
for Each in the_Normals'Range
loop
the_Normals (Each) := Origin_3D;
end loop;
for f in the_Facets'Range
loop
for p in Index_t' (1) .. 3
loop
Id := the_Facets (f) (p);
the_Normals (Id) := the_Normals (Id) + the_facet_Normals (f);
end loop;
end loop;
for p in the_Normals'Range
loop
Length := abs (the_Normals (p));
if almost_Zero (Length)
then the_Normals (p) := [0.0, -1.0, 0.0];
else the_Normals (p) := (1.0 / Length) * the_Normals (p);
end if;
end loop;
end;
free (the_Facets);
free (the_facet_Normals);
return the_Normals.all'Unchecked_Access;
end any_Normals_of;
function Normals_of (face_Kind : in primitive.facet_Kind;
Indices : in openGL.Indices;
Sites : in openGL.Sites) return access Normals
is
function my_Normals_of is new any_Normals_of (any_Index_t => Index_t,
any_Indices => openGL.Indices);
begin
return my_Normals_of (face_Kind,
Indices,
Sites).all'unchecked_Access;
end Normals_of;
function Normals_of (face_Kind : in primitive.facet_Kind;
Indices : in openGL.long_Indices;
Sites : in openGL.Sites) return access Normals
is
function my_Normals_of is new any_Normals_of (any_Index_t => long_Index_t,
any_Indices => openGL.long_Indices);
begin
return my_Normals_of (face_Kind,
Indices,
Sites).all'unchecked_Access;
end Normals_of;
---------
-- Bounds
--
function get_Bounds (Count : in Natural) return openGL.Bounds
is
use Geometry_3D;
the_Bounds : openGL.Bounds := null_Bounds;
begin
for i in 1 .. any_Index_t (Count)
loop
the_Bounds.Box := the_Bounds.Box
or get_Site (i);
the_Bounds.Ball := Real'Max (the_Bounds.Ball,
abs (get_Site (i)));
end loop;
return the_Bounds;
end get_Bounds;
---------------
-- Transparency
--
function get_Transparency (Count : in Natural) return Boolean
is
use type color_Value;
begin
for i in 1 .. any_Index_t (Count)
loop
if get_Color (i).Alpha /= opaque_Value
then
return True;
end if;
end loop;
return False;
end get_Transparency;
end openGL.Geometry;