wip scroll support

4 files changed, 87 insertions, 12 deletions

diff --git a/src/ada_chip.adb b/src/ada_chip.adb
index b6a7611..cd156f7 100644
--- a/src/ada_chip.adb
+++ b/src/ada_chip.adb
@@ -82,16 +82,20 @@ procedure Ada_Chip is
    end Draw_Sprite;
 
    procedure Run_Flow (ins : ISA.Opcode) is
+      use ISA;
    begin
-      case ins.Value is
-         when ISA.Clear_Screen => Video.Clear_Screen;
-         when ISA.Ret => CPU.Ret (State);
-         when ISA.Low_Res => Video.Low_Res;
-         when ISA.High_Res => Video.High_Res;
-         when others =>
-            Ada.Text_IO.Put_Line ("Machine code calls are unsupported!");
-            delay 1.0;
+      case Flow_Class'Enum_Val (ins.Value) is
+         when Scroll_Down_0 .. Scroll_Down_15 =>
+            null;
+         when Scroll_Right => Video.Scroll_Right;
+         when Scroll_Left => Video.Scroll_Left;
+         when Exit_Interpreter =>
+            Ada.Text_IO.Put_Line ("Exit interpreter not supported!");
             Video.Finish;
+         when Clear_Screen => Video.Clear_Screen;
+         when Ret => CPU.Ret (State);
+         when Low_Res => Video.Low_Res;
+         when High_Res => Video.High_Res;
       end case;
    end Run_Flow;
 
diff --git a/src/isa.ads b/src/isa.ads
index e5310d3..2552995 100644
--- a/src/isa.ads
+++ b/src/isa.ads
@@ -43,10 +43,40 @@ package ISA is
       Misc          => 15
    );
 
-   Clear_Screen : constant Opcode_Value := 16#E0#;
-   Ret          : constant Opcode_Value := 16#EE#;
-   Low_Res      : constant Opcode_Value := 16#FE#;
-   High_Res     : constant Opcode_Value := 16#FF#;
+   type Flow_Class is (
+      Scroll_Down_0, Scroll_Down_1, Scroll_Down_2, Scroll_Down_3,
+      Scroll_Down_4, Scroll_Down_5, Scroll_Down_6, Scroll_Down_7,
+      Scroll_Down_8, Scroll_Down_9, Scroll_Down_10, Scroll_Down_11,
+      Scroll_Down_12, Scroll_Down_13, Scroll_Down_14, Scroll_Down_15,
+      Clear_Screen, Ret, Scroll_Right, Scroll_Left, Exit_Interpreter, Low_Res,
+      High_Res
+   );
+
+   for Flow_Class use (
+      Scroll_Down_0  => 16#C0#,
+      Scroll_Down_1  => 16#C1#,
+      Scroll_Down_2  => 16#C2#,
+      Scroll_Down_3  => 16#C3#,
+      Scroll_Down_4  => 16#C4#,
+      Scroll_Down_5  => 16#C5#,
+      Scroll_Down_6  => 16#C6#,
+      Scroll_Down_7  => 16#C7#,
+      Scroll_Down_8  => 16#C8#,
+      Scroll_Down_9  => 16#C9#,
+      Scroll_Down_10 => 16#CA#,
+      Scroll_Down_11 => 16#CB#,
+      Scroll_Down_12 => 16#CC#,
+      Scroll_Down_13 => 16#CD#,
+      Scroll_Down_14 => 16#CE#,
+      Scroll_Down_15 => 16#CF#,
+      Clear_Screen   => 16#E0#,
+      Ret            => 16#EE#,
+      Scroll_Right   => 16#FB#,
+      Scroll_Left    => 16#FC#,
+      Exit_Interpreter => 16#FD#,
+      Low_Res        => 16#FE#,
+      High_Res       => 16#FF#
+   );
 
    type Math_Class is (
       Assign, Bit_Or, Bit_And, Bit_Xor, Add, Sub_Y, Shift_Right, Sub_X,
diff --git a/src/video.adb b/src/video.adb
index f4ddb6b..657d285 100644
--- a/src/video.adb
+++ b/src/video.adb
@@ -16,6 +16,44 @@ package body Video is
       end loop;
    end Clear_Screen;
 
+   procedure Scroll_Right is
+      use Sf.Graphics.Color;
+
+      SS  : constant sfUint32 := 4;
+      Tmp : array (0 .. SS - 1) of sfColor;
+   begin
+      for J in 0 .. Height - 1 loop
+         for I in 0 .. SS - 1 loop
+            Tmp (I) := Image.getPixel (Pixels, Width - SS + I, J);
+         end loop;
+         for I in 0 .. Width - 5 loop
+            Image.setPixel (Pixels, I + SS, J, Image.getPixel (Pixels, I, J));
+         end loop;
+         for I in 0 .. SS - 1 loop
+            Image.setPixel (Pixels, I, J, Tmp (I));
+         end loop;
+      end loop;
+   end Scroll_Right;
+
+   procedure Scroll_Left is
+      use Sf.Graphics.Color;
+
+      SS  : constant sfUint32 := 4;
+      Tmp : array (0 .. SS - 1) of sfColor;
+   begin
+      for J in 0 .. Height - 1 loop
+         for I in 0 .. SS - 1 loop
+            Tmp (I) := Image.getPixel (Pixels, I, J);
+         end loop;
+         for I in SS .. Width - 1 loop
+            Image.setPixel (Pixels, I - SS, J, Image.getPixel (Pixels, I, J));
+         end loop;
+         for I in 0 .. SS - 1 loop
+            Image.setPixel (Pixels, Width - SS + I, J, Tmp (I));
+         end loop;
+      end loop;
+   end Scroll_Left;
+
    procedure Low_Res is
    begin
       Video.Width := 64;
diff --git a/src/video.ads b/src/video.ads
index ec9b212..49d3c95 100644
--- a/src/video.ads
+++ b/src/video.ads
@@ -24,6 +24,9 @@ package Video is
    procedure Finish;
    procedure Poll_Events;
 
+   procedure Scroll_Right;
+   procedure Scroll_Left;
+
    function Key_Down (K : Key) return Boolean;
    function Key_Up (K : Key) return Boolean;
    function Is_Running return Boolean;