Added support for gl[Get]FramebufferParameter

src/gl/implementation/gl-api.ads

@@ -107,6 +107,11 @@ private package GL.API is
                            Target : in out Ints.Vector4);
    pragma Import (Convention => StdCall, Entity => Get_Int_Vec4,
                   External_Name => "glGetIntegerv");
+
+   procedure Get_Size (Name   : Enums.Getter.Parameter;
+                       Target : access Size);
+   pragma Import (Convention => StdCall, Entity => Get_Size,
+                  External_Name => "glGetIntegerv");
 
    procedure Get_Color_Control (Name   : Enums.Getter.Parameter;
                                 Target : access Fixed.Lighting.Color_Control);
@@ -810,6 +815,26 @@ private package GL.API is
       Objects.Framebuffers.Attachment_Point,
       Objects.Framebuffers.Attachment_List);
 
+   procedure Framebuffer_Parameter_Size is new Loader.Procedure_With_3_Params
+     ("glFramebufferParameteri", Low_Level.Enums.Framebuffer_Kind,
+      Enums.Framebuffer_Param, Size);
+
+   procedure Framebuffer_Parameter_Bool is new Loader.Procedure_With_3_Params
+     ("glFramebufferParameteri", Low_Level.Enums.Framebuffer_Kind,
+      Enums.Framebuffer_Param, Low_Level.Bool);
+
+   procedure Get_Framebuffer_Parameter_Size is new
+     Loader.Procedure_With_3_Params ("glGetFramebufferParameteriv",
+                                     Low_Level.Enums.Framebuffer_Kind,
+                                     Enums.Framebuffer_Param,
+                                     Low_Level.Size_Access);
+
+   procedure Get_Framebuffer_Parameter_Bool is new
+     Loader.Procedure_With_3_Params ("glGetFramebufferParameteriv",
+                                     Low_Level.Enums.Framebuffer_Kind,
+                                     Enums.Framebuffer_Param,
+                                     Low_Level.Bool_Access);
+
    -----------------------------------------------------------------------------
    --                                 Shaders                                 --
    -----------------------------------------------------------------------------

src/gl/implementation/gl-enums-getter.ads

@@ -245,7 +245,11 @@ package GL.Enums.Getter is
       Current_Fog_Coord,
       Active_Texture,
       Blend_Equation_Alpha,
-      Max_Combined_Texture_Image_Units);
+      Max_Combined_Texture_Image_Units,
+      Max_Framebuffer_Width,
+      Max_Framebuffer_Height,
+      Max_Framebuffer_Layers,
+      Max_Framebuffer_Samples);
    for Parameter use
      (Current_Color                 => 16#0B00#,
       Current_Index                 => 16#0B01#,
@@ -474,7 +478,11 @@ package GL.Enums.Getter is
       Current_Fog_Coord             => 16#8453#,
       Active_Texture                => 16#84E0#,
       Blend_Equation_Alpha          => 16#883D#,
-      Max_Combined_Texture_Image_Units => 16#8B4D#);
+      Max_Combined_Texture_Image_Units => 16#8B4D#,
+      Max_Framebuffer_Width         => 16#9315#,
+      Max_Framebuffer_Height        => 16#9316#,
+      Max_Framebuffer_Layers        => 16#9317#,
+      Max_Framebuffer_Samples       => 16#9318#);
    for Parameter'Size use Low_Level.Enum'Size;
 
    type String_Parameter is

src/gl/implementation/gl-enums.ads

@@ -86,6 +86,9 @@ private package GL.Enums is
                               Pack_Skip_Rows, Pack_Skip_Pixels,
                               Pack_Alignment, Pack_Skip_Images, Pack_Image_Height,
                               Unpack_Skip_Images, Unpack_Image_Height);
+
+   type Framebuffer_Param is (Default_Width, Default_Height, Default_Layers,
+                              Default_Samples, Default_Fixed_Sample_Locations);
 private
 
    for Attribute_Mask use record
@@ -179,4 +182,11 @@ private
                               Unpack_Skip_Images  => 16#806D#,
                               Unpack_Image_Height => 16#806E#);
    for Pixel_Store_Param'Size use Low_Level.Enum'Size;
+
+   for Framebuffer_Param use (Default_Width                  => 16#9310#,
+                              Default_Height                 => 16#9311#,
+                              Default_Layers                 => 16#9312#,
+                              Default_Samples                => 16#9313#,
+                              Default_Fixed_Sample_Locations => 16#9314#);
+   for Framebuffer_Param'Size use Low_Level.Enum'Size;
 end GL.Enums;

src/gl/implementation/gl-low_level.ads

@@ -57,6 +57,10 @@ package GL.Low_Level is
    subtype SizeIPtr is C.long;
 
    type CharPtr_Array is array (Positive range <>) of aliased C.Strings.chars_ptr;
+
+   -- used in API calls
+   type Size_Access is access all Types.Size;
+   type Bool_Access is access all Bool;
 private
    for Bool use (False => 0, True => 1);
    for Bool'Size use C.unsigned_char'Size;
@@ -65,4 +69,6 @@ private
    pragma Convention (C, Double_Array);
    pragma Convention (C, Int_Array);
    pragma Convention (C, UInt_Array);
+   pragma Convention (C, Size_Access);
+   pragma Convention (C, Bool_Access);
 end GL.Low_Level;

src/gl/implementation/gl-objects-framebuffers.adb

@@ -18,6 +18,7 @@ with Ada.Containers.Indefinite_Hashed_Maps;
 with Ada.Unchecked_Conversion;
 
 with GL.API;
+with GL.Enums.Getter;
 
 package body GL.Objects.Framebuffers is
    ------------
@@ -69,6 +70,124 @@ package body GL.Objects.Framebuffers is
       Raise_Exception_On_OpenGL_Error;
    end Blit;
 
+   procedure Set_Default_Width (Target : in out Framebuffer_Target;
+                                Value  : Size) is
+   begin
+      API.Framebuffer_Parameter_Size (Target.Kind, Enums.Default_Width, Value);
+      Raise_Exception_On_OpenGL_Error;
+   end Set_Default_Width;
+
+   function Default_Width (Target : Framebuffer_Target) return Size is
+      Ret : aliased Size;
+   begin
+      API.Get_Framebuffer_Parameter_Size
+        (Target.Kind, Enums.Default_Width, Ret'Unchecked_Access);
+      Raise_Exception_On_OpenGL_Error;
+      return Ret;
+   end Default_Width;
+
+   function Max_Framebuffer_Width return Size is
+      Ret : aliased Size;
+   begin
+      API.Get_Size (Enums.Getter.Max_Framebuffer_Width, Ret'Access);
+      Raise_Exception_On_OpenGL_Error;
+      return Ret;
+   end Max_Framebuffer_Width;
+
+   procedure Set_Default_Height (Target : in out Framebuffer_Target;
+                                 Value  : Size) is
+   begin
+      API.Framebuffer_Parameter_Size (Target.Kind, Enums.Default_Height,
+                                      Value);
+      Raise_Exception_On_OpenGL_Error;
+   end Set_Default_Height;
+
+   function Default_Height      (Target : Framebuffer_Target) return Size is
+      Ret : aliased Size;
+   begin
+      API.Get_Framebuffer_Parameter_Size (Target.Kind, Enums.Default_Height,
+                                          Ret'Unchecked_Access);
+      Raise_Exception_On_OpenGL_Error;
+      return Ret;
+   end Default_Height;
+
+   function Max_Framebuffer_Height return Size is
+      Ret : aliased Size;
+   begin
+      API.Get_Size (Enums.Getter.Max_Framebuffer_Height, Ret'Unchecked_Access);
+      Raise_Exception_On_OpenGL_Error;
+      return Ret;
+   end Max_Framebuffer_Height;
+
+   procedure Set_Default_Layers (Target : in out Framebuffer_Target;
+                                 Value  : Size) is
+   begin
+      API.Framebuffer_Parameter_Size (Target.Kind, Enums.Default_Layers, Value);
+      Raise_Exception_On_OpenGL_Error;
+   end Set_Default_Layers;
+
+   function Default_Layers      (Target : Framebuffer_Target) return Size is
+      Ret : aliased Size;
+   begin
+      API.Get_Framebuffer_Parameter_Size (Target.Kind, Enums.Default_Layers,
+                                          Ret'Unchecked_Access);
+      Raise_Exception_On_OpenGL_Error;
+      return Ret;
+   end Default_Layers;
+
+   function Max_Framebuffer_Layers return Size is
+      Ret : aliased Size;
+   begin
+      API.Get_Size (Enums.Getter.Max_Framebuffer_Layers, Ret'Unchecked_Access);
+      Raise_Exception_On_OpenGL_Error;
+      return Ret;
+   end Max_Framebuffer_Layers;
+
+   procedure Set_Default_Samples (Target : in out Framebuffer_Target;
+                                  Value  : Size) is
+   begin
+      API.Framebuffer_Parameter_Size (Target.Kind, Enums.Default_Samples,
+                                      Value);
+      Raise_Exception_On_OpenGL_Error;
+   end Set_Default_Samples;
+
+   function Default_Samples
+     (Target : Framebuffer_Target) return Size is
+      Ret : aliased Size;
+   begin
+      API.Get_Framebuffer_Parameter_Size (Target.Kind, Enums.Default_Samples,
+                                          Ret'Unchecked_Access);
+      Raise_Exception_On_OpenGL_Error;
+      return Ret;
+   end Default_Samples;
+
+   function Max_Framebuffer_Samples return Size is
+      Ret : aliased Size;
+   begin
+      API.Get_Size (Enums.Getter.Max_Framebuffer_Samples, Ret'Unchecked_Access);
+      Raise_Exception_On_OpenGL_Error;
+      return Ret;
+   end Max_Framebuffer_Samples;
+
+   procedure Set_Default_Fixed_Sample_Locactions
+     (Target : in out Framebuffer_Target; Value : Boolean) is
+   begin
+      API.Framebuffer_Parameter_Bool
+        (Target.Kind, Enums.Default_Fixed_Sample_Locations,
+         Low_Level.Bool (Value));
+      Raise_Exception_On_OpenGL_Error;
+   end Set_Default_Fixed_Sample_Locactions;
+
+   function Default_Fixed_Sample_Locations (Target : Framebuffer_Target)
+                                            return Boolean is
+      Ret : aliased Low_Level.Bool;
+   begin
+      API.Get_Framebuffer_Parameter_Bool
+        (Target.Kind, Enums.Default_Fixed_Sample_Locations,
+         Ret'Unchecked_Access);
+      Raise_Exception_On_OpenGL_Error;
+      return Boolean (Ret);
+   end Default_Fixed_Sample_Locations;
 
    procedure Initialize_Id (Object : in out Framebuffer) is
       New_Id : UInt := 0;
@@ -88,7 +207,6 @@ package body GL.Objects.Framebuffers is
       Object.Reference.Initialized := False;
    end Delete_Id;
 
-
    function Hash (Key : Low_Level.Enums.Framebuffer_Kind)
      return Ada.Containers.Hash_Type is
       function Value is new Ada.Unchecked_Conversion

src/gl/interface/gl-objects-framebuffers.ads

@@ -58,6 +58,32 @@ package GL.Objects.Framebuffers is
    procedure Invalidate (Target : in out Framebuffer_Target;
                          Attachments : Attachment_List);
 
+   procedure Set_Default_Width (Target : in out Framebuffer_Target;
+                                Value  : Size);
+   function Default_Width (Target : Framebuffer_Target) return Size;
+   function Max_Framebuffer_Width return Size;
+
+   procedure Set_Default_Height (Target : in out Framebuffer_Target;
+                                 Value  : Size);
+   function Default_Height      (Target : Framebuffer_Target) return Size;
+   function Max_Framebuffer_Height return Size;
+
+   procedure Set_Default_Layers (Target : in out Framebuffer_Target;
+                                 Value  : Size);
+   function Default_Layers      (Target : Framebuffer_Target) return Size;
+   function Max_Framebuffer_Layers return Size;
+
+   procedure Set_Default_Samples (Target : in out Framebuffer_Target;
+                                  Value  : Size);
+   function Default_Samples
+     (Target : Framebuffer_Target) return Size;
+   function Max_Framebuffer_Samples return Size;
+
+   procedure Set_Default_Fixed_Sample_Locactions
+     (Target : in out Framebuffer_Target; Value : Boolean);
+   function Default_Fixed_Sample_Locations (Target : Framebuffer_Target)
+                                            return Boolean;
+
    -- copy from current Read to current Draw framebuffer
    procedure Blit (Src_X0, Src_Y0, Src_X1, Src_Y1,
                    Dst_X0, Dst_Y0, Dst_X1, Dst_Y1 : Int;