Syntax10.Scn.Fnt
ParcElems
Alloc
Syntax24b.Scn.Fnt
StampElems
Alloc
14 Feb 96
Syntax10b.Scn.Fnt
Syntax10i.Scn.Fnt
(* AMIGA *)
MODULE Display1;	(* RC 11.12.92, cn 
	IMPORT
		SYSTEM, Amiga,Display,Pictures;
	CONST
		white = 0; grey1 = 1; grey2 = 2; grey3 = 3; grey4 = 4; black = 5;
		texture0 = 6; texture1 = 7; texture2 = 8; texture3 = 9;
		scrPat: ARRAY 10 OF LONGINT;
	PROCEDURE GetPatternSize*(pat: Display.Pattern; VAR w, h: INTEGER);
	(* Returns the pattern size. *)
		VAR p: Amiga.PatternInfoPtr;
	BEGIN p := SYSTEM.VAL(Amiga.PatternInfoPtr, pat); w := p.w; h := p.h
	END GetPatternSize;
	PROCEDURE ThisPattern*(n: INTEGER): Display.Pattern;
	(* Returns the n-th predefined pattern (corresponding to the printer patterns). If the pattern is not available,
		0 is returned. n must be >= 0. Currently 10 patterns are predefined (0 .. 9). *)
	BEGIN
		IF n >= LEN(scrPat) THEN RETURN 0
		ELSE RETURN scrPat[n]
		END
	END ThisPattern;
	PROCEDURE Line*(f: Display.Frame; col, X0, Y0, X1, Y1, mode: INTEGER);
	(* Draws a line from (X0, Y0) to (X1, Y1) inclusive, clipped against F.  For all line points (x, y) the following holds
	always: (min(X0, X1) <= x) & (x <= max(X0, X1) & (min(Y0, Y0) <= y) & (y <= max(Y0, Y1). *)
	BEGIN
		Pictures.Line(Display.screen,f,col,X0,Y0,X1,Y1,mode)
	END Line;
	PROCEDURE Ellipse*(f: Display.Frame; col, X, Y, A, B, mode: INTEGER);
	(* Draws an ellipse with center (X, Y) and radii A and B, clipped against F. For all ellipse points (x, y)  the following holds
		always: (X-A <= x) & (x < X+A) & (Y-B <= y) & (y < Y+B). When A = B the resulting ellipse has the same shape
		as the corresponding circle with R = A. *)
	BEGIN
		Pictures.Ellipse(Display.screen,f,col,X,Y,A,B,mode)
	END Ellipse;
	PROCEDURE Circle*(f: Display.Frame; col, X, Y, R, mode: INTEGER);
	(* Draws a circle with center (X, Y) and radius R, clipped against F. For all circle points (x, y)  the following holds always:
		(X-R <= x) & (x < X+R) & (Y-R <= y) & (y < Y+R). *)
	BEGIN
		Pictures.Circle(Display.screen,f,col,X,Y,R,mode)
	END Circle;
	PROCEDURE Init;
		VAR image: ARRAY 17 OF SET;
		PROCEDURE Repl(step: INTEGER);
			VAR i: INTEGER;
		BEGIN i := step;
			WHILE i < 16 DO image[i+1] := image[i-step+1]; INC(i) END
		END Repl;
	BEGIN
		(*-- initialize screen patterns ---*)
		image[1] := {};
		Repl(1);
		scrPat[white] := Display.NewPattern(image, 16, 16);
		image[4] := {0, 8};
		image[3] := {};
		image[2] := {4, 12};
		image[1] := {};
		Repl(4);
		scrPat[grey1] := Display.NewPattern(image, 16, 16);
		image[2] := {0, 4, 8, 12};
		image[1] := {2, 6, 10, 14};
		Repl(2);
		scrPat[grey2] :=  Display.NewPattern(image, 16, 16);
		image[1] := {0, 2, 4, 6, 8, 10, 12, 14};
		image[0] := {1, 3, 5, 7, 9, 11, 13, 15};
		Repl(2);
		scrPat[grey3] :=  Display.NewPattern(image, 16, 16);
		image[2] := {1..3, 5..7, 9..11, 13..15};
		image[1] := {0, 1, 3..5, 7..9, 11..13, 15};
		Repl(2);
		scrPat[grey4] :=  Display.NewPattern(image, 16, 16);
		image[1] := {0..15};
		Repl(1);
		scrPat[black] := Display.NewPattern(image, 16, 16);
		image[4] :={3, 7, 11, 15};
		image[3] :={2, 6, 10, 14};
		image[2] :={1, 5, 9, 13};
		image[1] :={0, 4, 8, 12};
		Repl(4);
		scrPat[texture0] := Display.NewPattern(image, 16, 16);
		image[4] :={0, 4, 8, 12};
		image[3] :={1, 5, 9, 13};
		image[2] :={2, 6, 10, 14};
		image[1] :={3, 7, 11, 15};
		Repl(4);
		scrPat[texture1] := Display.NewPattern(image, 16, 16);
		image[1] := {2, 6, 10, 14};
		Repl(1);
		scrPat[texture2] := Display.NewPattern(image, 16, 16);
		image[4] := {};
		image[3] := {};
		image[2] := {};
		image[1] := {0..15};
		Repl(4);
		scrPat[texture3] := Display.NewPattern(image, 16, 16)
	END Init;
BEGIN
	Init
END Display1.