Syntax10.Scn.Fnt
Syntax10b.Scn.Fnt
MODULE PictureFrames;	(* << RC *)
IMPORT
	Display, Oberon, Viewers, MenuViewers, Pictures, TextFrames, Input, Files, Texts, Fonts, SYSTEM;
CONST
	black = Pictures.black; white = Pictures.white;	ML = 2;	MM = 1;	MR = 0; CR = 0DX;	TAB = 09X;
CONST redraw* = 0; resize* = 1;
	UpdateMsg* = RECORD
		(Display.FrameMsg)
		id* : INTEGER;
		pict* : Pictures.Picture;
		x*, y*, w*, h* : INTEGER
	END;
	CopyOverMsg* = RECORD (Display.FrameMsg)
		pict*: Pictures.Picture;
		x*, y*, w*, h* : INTEGER
	END;
	Location* = POINTER TO LocDesc;
	LocDesc* = RECORD
		x*, y* : INTEGER;
		next* : Location
	END;
	Frame* = POINTER TO FrameDesc;
	FrameDesc* = RECORD
		(Display.FrameDesc);
		l*, t* : INTEGER; (* left, top of pict *)
		pict* : Pictures.Picture;
		car*, sel*, zoom* : INTEGER;
		time* : LONGINT;
		caret* : Location;
		selx*, sely*, selw*, selh* : INTEGER;
		string : RECORD
			 len, x, y  : INTEGER
		END
	END;
	SelectionMsg = RECORD
		(Display.FrameMsg)
		time : LONGINT;
		pict : Pictures.Picture;
		x, y, w, h : INTEGER
	END;
	Pattern = ARRAY 9 OF LONGINT;
	lineWidth*,grid*,color* : INTEGER;
	smooth : BOOLEAN;
	menuString* : ARRAY 100 OF CHAR;
	cancel : SET;
	resizePicture : Pictures.Picture;
	F  : Frame;
PROCEDURE max (i, j: INTEGER): INTEGER; BEGIN IF i >= j THEN RETURN i ELSE RETURN j END END max;
PROCEDURE min (i, j: LONGINT): INTEGER; BEGIN  IF i >= j THEN RETURN SHORT(j) ELSE RETURN SHORT(i) END END min;
PROCEDURE SetToDisplay(F : Frame;  VAR DX, DY : INTEGER);
	VAR R : INTEGER;
BEGIN
	R := F.zoom DIV 2;
	DX := (DX - 1 + R) DIV F.zoom * F.zoom + 1; DY := (DY -1 + R) DIV F.zoom * F.zoom +1
END SetToDisplay;
PROCEDURE Loc*(F : Frame; X,Y: INTEGER; VAR DX,DY : INTEGER);
	(* Yp = (Yf - F.Y) - (F.H - F.t); *)
BEGIN
	DX := F.X + (X - F.l) * F.zoom; DY := F.Y + F.H + (Y - F.t) * F.zoom;
	SetToDisplay(F,DX,DY)
END Loc;
PROCEDURE Pos*(F : Frame; DX,DY: INTEGER; VAR X, Y : INTEGER);
	(* Yp = (Yf - F.Y) - (F.H - F.t); *)
		VAR R : INTEGER;
BEGIN
	R := F.zoom DIV 2;
	X := (DX - F.X - R-1) DIV F.zoom + F.l+1; Y := (DY - F.Y - F.H - R - 1 ) DIV F.zoom + F.t  + 1
END Pos;
PROCEDURE SetToGrid(F : Frame; VAR X,Y : INTEGER);
BEGIN
	X := (X + grid DIV 2) DIV grid * grid; Y := (Y + grid DIV 2) DIV grid * grid
END SetToGrid;
PROCEDURE SetToDGrid(F: Frame; VAR DX,DY : INTEGER);
	VAR x,y : INTEGER;
BEGIN
	Pos(F,DX,DY,x,y); SetToGrid(F,x,y); Loc(F,x,y,DX,DY)
END SetToDGrid;
PROCEDURE DrawCaret(F : Frame; X, Y : INTEGER);
	CONST C = 5;
	VAR DX, DY, W : INTEGER;
BEGIN
	Loc(F,X,Y,DX,DY); DX := DX - C; DY := DY - C;  W := 2*C +1;
	IF (DX > F.X) & (DY > F.Y) & (DX + W < F.X + F.W) & (DY + W < F.Y + F.H) THEN
		Display.ReplConst(white,DX,DY+C,W,1,Display.invert);
		Display.ReplConst(white,DX+C,DY,1,W,Display.invert)
END DrawCaret;
PROCEDURE SetCaret*(F : Frame; X, Y : INTEGER);
(** set caret in frame F *)
	VAR c : Location;
BEGIN
	INC(F.car);
	NEW(c); c.x := X; c.y :=Y; c.next := F.caret; F.caret := c;
	DrawCaret(F,X,Y)
END SetCaret;
PROCEDURE ClipPicture(P : Pictures.Picture; VAR X,Y,W,H : INTEGER);
	VAR R,T : INTEGER;
BEGIN
	R := X + W; T := Y + H;
	X := max(0,X); Y := max(0,Y); W := min(P.width,R) - X ; H := min(P.height,T) - Y
END ClipPicture;
PROCEDURE CopyOver*(F : Frame; picture : Pictures.Picture; X, Y, W, H : INTEGER);
	VAR DX,DY :INTEGER;
BEGIN
	IF F.car > 0 THEN
		ClipPicture(F.pict,F.caret.x,F.caret.y,W,H);
		IF (W>0) & (H > 0) THEN
			Pictures.CopyBlock(picture,F.pict,X,Y,W,H,F.caret.x,F.caret.y,Display.replace);
			Pictures.Update(F.pict,F.caret.x,F.caret.y,W,H)
		END
END CopyOver;
PROCEDURE Defocus*(F : Frame);
	VAR c : Location;
BEGIN
	c := F.caret;
	WHILE c # NIL DO DrawCaret(F,c.x,c.y); c := c.next END;
	F.caret := NIL; F.car := 0
END Defocus;
PROCEDURE ClipFrame(F : Frame; VAR X, Y , W, H, DX, DY : INTEGER);
	VAR R, T, dX,dY : INTEGER;
BEGIN
	Loc(F,X,Y,dX,dY);
	DX := max(dX,F.X); DY := max(F.Y,dY);
	SetToDisplay(F,DX , DY ); SetToDisplay(F,dX , dY );
	Pos(F,DX,DY,X,Y);
	W := (min(dX + W * F.zoom, F.X+ F.W) - DX) DIV F.zoom; H := (min(dY+ H * F.zoom,F.Y + F.H) - DY) DIV F.zoom;
	IF DY < F.Y THEN INC(DY,8); INC(Y); DEC(H) END;
	IF DX + W*F.zoom > F.X + F.W THEN DEC(W) END
END ClipFrame;
PROCEDURE ReplConst (F : Frame; col, X, Y, W, H, mode: INTEGER);
	VAR D : INTEGER;
BEGIN
	IF X < F.X THEN DEC(W,F.X - X); X := F.X END; D :=  X + W - F.X - F.W; IF D >  0 THEN DEC(W,D)END;
	IF Y < F.Y THEN DEC(H,F.Y - Y); Y := F.Y END; D := Y + H - F.Y - F.H; IF D > 0 THEN DEC(H,D) END;
	IF (W > 0) & (H > 0) THEN
		Display.ReplConst(col, X, Y, W, H, mode)
END ReplConst;
PROCEDURE Rectangle(F : Frame; DX,DY,W,H : INTEGER);
BEGIN
	ReplConst(F,white,DX,DY,W,1,Display.invert); (* bottom *)
	ReplConst(F,white,DX+W,DY,1,H,Display.invert); (* right *)
	IF H > 0 THEN ReplConst(F,white,DX+1,DY+H, W,1,Display.invert)END;(* top *)
	IF W > 0 THEN ReplConst(F,white,DX,DY+1,1,H,Display.invert) END(* left *)
END Rectangle;
PROCEDURE RemoveSelection*(F : Frame);
(** remove selection from frame F *)
	VAR DX, DY :  INTEGER;
BEGIN
	IF F.sel # 0 THEN
		Loc(F,F.selx,F.sely,DX,DY); Rectangle(F,DX,DY,F.selw *F.zoom,F.selh*F.zoom); F.sel := 0
END RemoveSelection;
PROCEDURE SetSelection*(F : Frame; X, Y, W, H : INTEGER);
(** set (change) selection  in frame F *)
	VAR DX,DY : INTEGER;
BEGIN
	RemoveSelection(F);
	IF W > 0  THEN F.selx := X; F.selw := W  ELSE F.selx := X + W; F.selw := - W  END;
	IF H > 0  THEN F.sely := Y; F.selh := H  ELSE F.sely := Y + H; F.selh := - H  END;
	Loc(F,F.selx,F.sely,DX,DY); Rectangle(F,DX,DY,F.selw*F.zoom, F.selh* F.zoom);
	F.time := Oberon.Time(); F.sel := 1
END SetSelection;
PROCEDURE TrackRect(F : Frame; VAR mX, mY : INTEGER;VAR mkeys : SET;  VAR x, y, w, h : INTEGER);
	VAR X, Y, dX, dY,DX,DY, W, H : INTEGER; keys,M: SET;
BEGIN
	Pos(F,mX,mY,X, Y); dX := X - x; dY := Y - y; M := mkeys;
	REPEAT
		W := w; H := h; ClipFrame(F,x, y, W, H,DX,DY); Rectangle(F,DX, DY, W* F.zoom, H*F.zoom);
		X := mX; Y := mY; keys := mkeys;
		WHILE  (mX = X) & (Y = mY) & (keys = mkeys) DO
			Input.Mouse(mkeys, mX, mY); Oberon.DrawCursor(Oberon.Mouse, Oberon.Arrow, mX, mY)
		END;
		M := M + mkeys;
		Rectangle(F,DX, DY, W* F.zoom, H*F.zoom);
		Pos(F,mX,mY, X, Y); x := X -dX; y := Y -dY
	UNTIL mkeys = {};
	mkeys := M
END TrackRect;
PROCEDURE TrackSelection*(F : Frame; DX, DY : INTEGER; VAR keys : SET) ;
	(** tracks selection in Frame F *)
	VAR  M, k : SET; x0, y0,x, y, u,v,X, Y : INTEGER; t: INTEGER;
BEGIN
	Pos(F,DX,DY,X,Y); SetToGrid(F,X,Y); x0 := DX; y0 := DY; x := x0; y := y0; k := keys; M := keys;
	WHILE keys # {} DO
		REPEAT
			Input.Mouse(k, u, v); Oberon.DrawCursor(Oberon.Mouse, Oberon.Arrow, u, v)
		UNTIL (x # u) OR (y # v) OR (k # keys);
		RemoveSelection(F);
		t := min(F.Y+F.H-1,max(F.Y,v));
		Pos(F,min(F.X + F.W -1,max(F.X,u)),t,x,y); SetToGrid(F,x,y);
		SetSelection(F,X,Y,x-X,y-Y);
		x := u; y := v; keys := k; M := M + keys
	END;
	keys := M
END TrackSelection;
PROCEDURE GraphicSelection(VAR G : Graphics.Graph; VAR time : LONGINT);
	VAR GF : Graphics.Frame; F : Display.Frame;
BEGIN
	F := Oberon.MarkedViewer();
	IF F IS Graphics.Frame THEN
		GF := F(Graphics.Frame); G := GF.graph; time := Oberon.Time()
	ELSE
		time := 0
END GraphicSelection;
PROCEDURE CopyGraph(G : Graphics.Graph; F : Frame);
	VAR GF : Graphics.Frame;
BEGIN
	NEW(GF); GF.X := F.X; GF.Y := F.Y; GF.W := F.W; GF.H := F.H;
	GF.X1 := GF.X + GF.W; GF.Y1 := GF.Y + GF.H;
	GF.x := GF.X - GF.Xg; GF.y := GF.Y - GF.Yg
END CopyGraph;
PROCEDURE GetSelection*(VAR P : Pictures.Picture; VAR time : LONGINT; VAR x, y, w, h : INTEGER);
(** get most recent selection.  *)
	VAR i : INTEGER; msg : SelectionMsg;
BEGIN
	msg.time :=  -1; msg.pict := NIL;
	Viewers.Broadcast(msg);
	P := msg.pict; time := msg.time; x := msg.x; y := msg.y; w := msg.w; h := msg.h;
	IF time > 0 THEN ClipPicture(P,x,y,w,h) END
END GetSelection;
PROCEDURE Neutralize* (F: Frame);
	(** neutralize viewer V *)
		VAR cMsg : Oberon.InputMsg;
BEGIN
	Oberon.RemoveMarks(F.X, F.Y, F.W, F.H);
	Defocus(F);
	RemoveSelection(F)
END Neutralize;
PROCEDURE RestoreBack(F : Frame; X, Y, W, H : INTEGER);
	VAR DX,DY, B, H0 , fB, fT, fL, fR : INTEGER;
BEGIN
	Neutralize(F);
	(*	Oberon.FadeCursor(Oberon.Mouse); *)
	ClipPicture(F.pict,X,Y,W,H);
	ClipFrame(F,X,Y,W,H,DX,DY);
	H0 := min((F.pict.height - Y) * F.zoom,F.Y + F.H - DY);
	Loc(F,0,F.pict.height,L,T);  H0 :=  min(T,F.Y + F.H) - DY;
	IF (H0 <= 0) OR (W <= 0) THEN
		Display.ReplConst(black,F.X,F.Y, F.W, F.H, Display.replace)
	ELSIF (H >0) & (W > 0) THEN
		(* draw frame *)
		(* bottom *) IF Y = 0 THEN ReplConst(F,white,DX-1,DY-1,W * F.zoom+2,1,Display.replace); fB := 1 ELSE fB := 0 END;
		(* left *) IF X = 0 THEN ReplConst(F,white,DX-1,DY,1,H*F.zoom,Display.replace); fL := 1 ELSE fL := 0 END;
		(* top *) IF Y + H0 DIV F.zoom = F.pict.height  THEN ReplConst(F,white,DX-1,DY + H0,W * F.zoom+2, 1, Display.replace); fT := 1 ELSE fT := 0 END;
		(* right *) IF  X + W = F.pict.width THEN ReplConst(F,white,DX + W * F.zoom, DY, 1, H *F.zoom, Display.replace); fR := 1 ELSE fR := 0  END;
		(* bottom *) ReplConst(F,black,F.X,F.Y,F.W,DY-F.Y-fB,Display.replace);
		(* top *) ReplConst(F,black,F.X,DY + H0 + fT,F.W,F.Y + F.H  - (DY + H0) - fT,Display.replace);
		(* left *) ReplConst(F,black,F.X,DY-1,DX - F.X-fL,H*F.zoom + 2  ,Display.replace);
		(* right *) ReplConst(F,black,DX + W*F.zoom+fR,DY - 1,F.X + F.W - (DX + W*F.zoom)-fR,H*F.zoom+ 2,Display.replace);
		IF F.zoom # 1 THEN
			H0 := (F.H + F.Y - DY) DIV F.zoom * F.zoom;
			ReplConst(F,black,F.X,DY + H0 + fT, F.W, F.Y + F.H  - (DY + H0) - fT, Display.replace)
		END
END RestoreBack;
PROCEDURE DisplayBlock(F : Frame; X, Y, W, H, DX, DY : INTEGER);
	VAR x, y : INTEGER; P : Pictures.Picture;
BEGIN y := 0; P := F.pict;
	Display.ReplConst(black,DX,DY,W*8,H*8,Display.replace);
	WHILE y < H DO x := 0;
		WHILE x < W DO
			Display.ReplConst( Pictures.Get(P,X + x,Y + y),DX + x * 8 , DY + y * 8,7, 7,Display.replace);
			INC(x)
		END;
		INC(y)
END DisplayBlock;
PROCEDURE RestorePicture(F : Frame; X, Y, W, H : INTEGER);
	VAR DX, DY ,Z : INTEGER;
BEGIN
	Neutralize(F);
	(* 	Oberon.FadeCursor(Oberon.Mouse); *)
	ClipPicture(F.pict,X,Y,W,H);
	ClipFrame(F,X,Y,W,H,DX,DY);
	IF (H > 0) & (W > 0) THEN
		IF F.zoom = 1 THEN
			Pictures.DisplayBlock(F.pict,X, Y, W, H, DX, DY, Display.replace)
		ELSE
			SetToDisplay(F,DX,DY);
			DisplayBlock(F,X, Y, W, H, DX, DY)
		END
END RestorePicture;
PROCEDURE Restore*(F : Frame);
BEGIN
	Neutralize(F);
	RestorePicture(F,0,0,F.pict.width,F.pict.height);
	RestoreBack(F,0,0,F.pict.width,F.pict.height)
END Restore;
PROCEDURE NotifyDisplay*(P : Pictures.Picture; X,Y,W,H : INTEGER);
	VAR msg : UpdateMsg;
BEGIN
	msg.x := X; msg.y := Y; msg.w := W;msg.h := H; msg.id := redraw; msg.pict := P;
	Viewers.Broadcast(msg)
END NotifyDisplay;
PROCEDURE ResizePicture(F: Frame; P : Pictures.Picture; x, y : INTEGER);
BEGIN
	F.sel :=  0;
	Neutralize(F);
	F.pict := resizePicture;
	DEC(F.l,x);  DEC(F.t, y);
	Restore(F)
END ResizePicture;
PROCEDURE Resize*(F : Frame; X, Y, W, H : INTEGER);
	VAR P : Pictures.Picture; msg : UpdateMsg;
BEGIN
	NEW(P); Pictures.Create(P,F.selw,F.selh,F.pict.depth); P.notify := NotifyDisplay;
	Pictures.CopyBlock(F.pict,P,X,Y,W,H,X-F.selx,Y-F.sely,Display.replace);
	resizePicture := P;
	msg.pict := F.pict;  msg.x := F.selx; msg.y := F.sely; msg.id := resize;
	Viewers.Broadcast(msg)
END Resize;
PROCEDURE Write*(F : Frame; font : Fonts.Font; col : INTEGER; ch : CHAR; VAR x, y : INTEGER; mode : INTEGER);
(**  write ch at position x, y; after write x,y points to new position; CR(=0DX) is processed  *)
	VAR pat: Display.Pattern; dx,u,v,w,h: INTEGER; P : Pictures.Picture;
BEGIN
	P := F.pict;
	IF  (x # F.string.x) OR (y # F.string.y)  THEN  F.string.len := 0 END;
	dx := 0;
	IF ch = CR THEN
		y := y  - font.height; x := x - F.string.len; F.string.len := 0
	ELSIF  (ch >= " ")  OR (ch = TAB)  THEN
		Display.GetChar(font.raster,ch,dx,u,v,w,h,pat);
		IF (x >= 0) & (x + w < P.width) & (y >= 0) & (y +h < P.height) (*& (P.depth =1 )*) THEN
			Pictures.CopyPattern(P,col,pat,x + u, y + v, mode)
		END
	END;
	x := x + dx;
	INC(F.string.len,dx); F.string.x := x; F.string.y := y
END Write;
PROCEDURE Line(F : Frame; col, x1, y1, x2, y2, mode : INTEGER; disp, first : BOOLEAN);
	x, y, d, dx,dy, incx, incy, DX, DY  : INTEGER;  P : Pictures.Picture;
	PROCEDURE Dot;
	BEGIN
		IF disp THEN
			Loc(F,x,y,DX,DY);
			IF (DX >= F.X) & (DY >= F.Y) & (DX  < F.X + F.W) & (DY < F.Y + F.H) THEN
				IF F. zoom = 1 THEN
					Display.ReplConst(col,DX,DY,1,1,mode)
				ELSE
					ReplConst(F,col,DX,DY,F.zoom-1,F.zoom-1,mode)
				END
			END
		ELSE
			IF (x >= 0) & (y >= 0) & (x + lineWidth <= P.width) & (y +  lineWidth <= P.height) THEN
				Pictures.ReplConst(P,col,x,y,lineWidth,lineWidth,mode)
			END
		END
	END Dot;
BEGIN
	P := F.pict;
	x := x1; y := y1; dx := (x2-x1)*2; dy := (y2-y1)*2;
	IF first THEN Dot END;
	incx := 0;
	IF dx < 0 THEN incx := -1; dx := -dx ELSIF dx>0 THEN incx := 1 END;
	incy := 0;
	IF dy < 0 THEN incy := -1; dy := -dy ELSIF dy>0 THEN incy := 1 END;
	d := incx*(x1-x2);
	IF dx>dy THEN
		WHILE x#x2 DO INC(x, incx); INC(d, dy);
			IF d>0 THEN INC(y, incy); DEC(d, dx) END;
			Dot
		END
	ELSE
		WHILE y#y2 DO INC(y, incy); INC(d, dx);
			IF d>0 THEN INC(x, incx); DEC(d, dy) END;
			Dot
		END
END Line;
PROCEDURE WriteText*(F : Frame; X,Y : INTEGER; text : Texts.Text; beg, end : LONGINT);
	VAR R : Texts.Reader; ch : CHAR;
BEGIN
	Texts.OpenReader(R,text,beg); Texts.Read(R,ch);
	WHILE beg < end DO
		Write(F,R.fnt,R.col, ch, X, Y, Display.paint);	(* << RC *)
		Texts.Read(R,ch); INC(beg)
	END;
	Pictures.Update(F.pict,0,0,F.pict.width,F.pict.height);
	SetCaret(F,X,Y)
END WriteText;
PROCEDURE Modify* (F: Frame; id, dY, Y, H: INTEGER);
	VAR V : Viewers.Viewer;  dH,X : INTEGER;
BEGIN
	dH := H - F.H;
	IF F.H = 0 THEN
		F.Y := Y; F.H := H; Display.ReplConst(black,F.X,F.Y,F.W,F.H,Display.replace);
		Restore(F)
	ELSE
		F.Y := Y; F.H := H;
		IF F.zoom # 1 THEN
			IF id = MenuViewers.extend THEN ReplConst(F,black, F.X, F.Y + F.H - dY, F.W, dY, Display.replace) END;
			Pos(F,F.X,F.Y,X,Y);
			RestorePicture(F,0,Y,F.pict.width*8,F.pict.height*8); RestoreBack(F,0,Y,F.pict.width,F.H)
		ELSE
			IF id = MenuViewers.extend THEN
				IF (dY # 0) & (F.zoom = 1) THEN
					Display.CopyBlock(F.X,Y,F.W,H-dY,F.X,Y+dY, Display.replace);
					Display.ReplConst(black,F.X,Y,F.W,dY,Display.replace)
				END;
				Pos(F,F.X,F.Y,X,Y);
				RestorePicture(F,0,Y,F.pict.width,dH); RestoreBack(F,0,Y,F.pict.width,dH)
			ELSIF id = MenuViewers.reduce THEN
				IF H # 0 THEN
					IF dY # 0 THEN
						Display.CopyBlock(F.X,Y+dY,F.W,H,F.X,Y, Display.replace)
					END
				END
			END
		END
END Modify;
PROCEDURE Copy*(F : Frame; VAR F1 : Frame);
BEGIN
	Neutralize(F);
	NEW(F1); F1^ := F^; F1.H := 0
END Copy;
PROCEDURE TrackMouse(VAR keys : SET; VAR X,Y : INTEGER);
BEGIN
	REPEAT Input.Mouse(keys, X, Y); Oberon.DrawCursor(Oberon.Mouse, Oberon.Arrow, X, Y) UNTIL keys = {}
END TrackMouse;
PROCEDURE TrackCopy(F : Frame; P : Pictures.Picture;  X, Y , W, H, X0, Y0, DX, DY, mode: INTEGER; VAR keys: SET);
	VAR x, y, u, v , x0, y0,  deltaX, deltaY : INTEGER; k ,M: SET; B, B0 : Pictures.Picture; wth : INTEGER;
	PROCEDURE CopyBlock(S, D : Pictures.Picture; X, Y , W, H, DX,DY : INTEGER);
		PROCEDURE Clip(D  : Pictures.Picture; VAR X,Y,W,H,DX,DY : INTEGER);
		BEGIN
			IF DX < 0 THEN INC(W,DX); DEC(X,DX); DX := 0 END;
			IF DY < 0  THEN INC(H,DY); DEC(Y,DY); DY := 0 END;
			IF DX + W > D.width THEN  DEC(W,DX + W - D.width ) END;
			IF DY + H > D.height THEN DEC(H, DY + H- D.height) END
		END Clip;
	BEGIN
		Clip(D,X,Y,W,H,DX,DY);
		Clip(S,DX,DY,W,H,X,Y);
		IF (W > 0) & (H > 0) THEN
			Pictures.CopyBlock(S,D,X, Y , W, H, DX,DY,Display.replace)
		END
	END CopyBlock;
BEGIN
	IF (W > 0) & (H > 0)  THEN
		SetToDGrid(F,DX,DY); Pos(F,DX,DY,x0,y0);  deltaX := X0 - x0; deltaY := Y0 - y0;
		x := DX; y := DY; k := keys; M := keys;
		IF ~ smooth OR (F.zoom # 1) THEN
			RemoveSelection(F);
			u := X0; v := Y0;
			TrackRect(F,DX,DY,keys,u, v,W, H);
			IF keys # cancel THEN
				IF mode = Display.replace THEN
					NEW(B0); Pictures.Create(B0,W,H,P.depth); CopyBlock(F.pict,B0,X,Y,W,H,0,0);
					Pictures.ReplConst(F.pict,black,X0,Y0,W,H,Display.replace);
					CopyBlock(B0,F.pict,0,0,W,H,u,v)
				ELSE
					CopyBlock(P,F.pict, X, Y, W, H, u,v)
				END
			END
		ELSE
			NEW(B0); Pictures.Create(B0,W,H,P.depth); CopyBlock(F.pict,B0,X,Y,W,H,0,0);
			NEW(B); Pictures.Create(B,W,H,P.depth);
			IF mode = Display.replace THEN
				IF F.pict = P THEN P := B0; X := 0; Y := 0 END;
				Pictures.ReplConst(F.pict,black,X0,Y0,W,H,Display.replace)
			END;
			CopyBlock(F.pict,B,(x0 + (x-DX) + deltaX),y0 + (y-DY ) + deltaY,W,H, 0, 0); (* save *)
			WHILE (keys # {}) & (M # cancel) DO
				REPEAT  Input.Mouse(k, u, v); SetToDGrid(F,u,v) UNTIL (u # x) OR (v # y) OR (k # keys);
				M := M + k;
				CopyBlock(B,F.pict,0,0,W,H,(x0 + (x-DX) DIV F.zoom + deltaX),y0 + (y-DY ) DIV F.zoom + deltaY); (* restore *)
				IF M # cancel THEN
					CopyBlock(F.pict,B,(x0 + (u-DX)  DIV F.zoom  + deltaX),y0 + (v-DY ) DIV F.zoom  + deltaY,W,H, 0, 0); (* save *)
					CopyBlock(P,F.pict,X,Y,W,H, x0 + (u-DX) DIV F.zoom  + deltaX,y0 + (v-DY ) DIV F.zoom  + deltaY); (* new *)
					RestorePicture(F,0,0,F.pict.width,F.pict.height)
				ELSE
					IF mode # Display.paint THEN
						CopyBlock(B0,F.pict,0,0,W,H,X0,Y0)
					END
				END;
				x := u; y := v; keys := k;
				Oberon.DrawCursor(Oberon.Mouse, Oberon.Arrow, x, y)
			END
		END;
		Pictures.Update(F.pict,0,0,F.pict.width,F.pict.height)
	END;
	TrackMouse(keys,X,Y); keys := M
END TrackCopy;
PROCEDURE Edit*(F : Frame;  X, Y: INTEGER; keys: SET);
	VAR x, y, u, v , x0, y0, w, h, l, t : INTEGER; M,k : SET; beg,end, time, time2 : LONGINT; P : Pictures.Picture; cMsg : CopyOverMsg;
		text : Texts.Text; line, ln : Location;
BEGIN
	IF keys = {ML} THEN
		x := X; y := Y;
		REPEAT
			Input.Mouse(k, u, v);
			Oberon.DrawCursor(Oberon.Mouse, Oberon.Arrow, u, v)
		UNTIL (ABS(u-X) > 4) OR (ABS(v -Y) > 4) OR (k # {ML});
		keys := k;
		IF (keys = {}) OR ((keys = {ML,MR}) & (F.car # 0)) THEN
			IF  (F.car = 0) (*Viewers.This(F.X,F.Y) # Oberon.FocusViewer*) OR (keys = {})  THEN Oberon.PassFocus(Viewers.This(u,v)) END;
			REPEAT
				WHILE (keys # {}) & (keys # {ML}) DO Input.Mouse(keys, u, v); Oberon.DrawCursor(Oberon.Mouse, Oberon.Arrow, u, v) END;
				Pos(F,u,v,X,Y); SetToGrid(F,X,Y); SetCaret(F,X,Y);
				WHILE keys = {ML} DO Input.Mouse(keys, u, v); Oberon.DrawCursor(Oberon.Mouse, Oberon.Arrow, u, v) END
			UNTIL keys = {}
		ELSIF keys = {ML,MM} THEN
			GetSelection(P,time,x,y,w,h);
			Oberon.GetSelection(text, beg, end, time2);
			IF (time > time2) & (time > 0) THEN
				Pos(F,X,Y,u,v); SetToGrid(F,u,v); keys := {ML};
				TrackCopy(F,P,x,y,w,h,u,v,X,Y,Display.paint,keys)
			ELSIF time2 > 0 THEN
				Pos(F,u,v,X,Y); SetCaret(F,X,Y);
				WriteText(F,X,Y,text,beg,end);
				TrackMouse(keys,X,Y)
			END
		ELSIF keys # {} THEN
			Pos(F,x,y,x0,y0); SetToGrid(F,x0,y0); M := keys; keys := {};
			NEW(line); line.x := x0; line.y := y0;
			Line(F,Display.white,x0,y0,x0,y0,Display.invert,TRUE,TRUE);
			REPEAT
				Pos(F,u,v,X,Y); SetToGrid(F,X,Y);
				Line(F,Display.white,x0,y0,X,Y,Display.invert,TRUE,FALSE);
				x := u; y := v;
				REPEAT
					Input.Mouse(k, u, v); Oberon.DrawCursor(Oberon.Mouse, Oberon.Arrow, u, v)
				UNTIL (keys # k) OR (x # u) OR (y # v);
				M := M + k; keys := k;
				IF keys = {ML,MR} THEN
					NEW(ln); ln.next:= line; line := ln;
					ln.x := X; ln.y := Y; x0 := X; y0 := Y
				ELSE
					Line(F,Display.white,x0,y0,X,Y,Display.invert,TRUE,FALSE)
				END
			UNTIL keys = {};
			IF M # cancel THEN
				ln := line;
				WHILE ln.next # NIL DO
					Line(F,color,ln.next.x,ln.next.y,ln.x,ln.y,Display.replace,FALSE,TRUE);
					ln := ln.next
				END
			END;
			Pictures.Update(F.pict,0,0,F.pict.width,F.pict.height);
			RestoreBack(F,0,0,F.pict.width,F.pict.height)
		END
	ELSIF keys = {MM} THEN
		Pos(F,X,Y,u,v);
		IF (F.sel > 0) & (u > F.selx) & (v > F.sely) & (u <= F.selx + F.selw) & (v <= F.sely + F.selh) THEN
			GetSelection(P,time,x,y,w,h);
			TrackCopy(F,P,x,y,w,h,x,y,X,Y,Display.replace,keys)
		ELSE
			l := F.l; t := F.t; M := keys;
			WHILE (keys # {}) & (M # cancel)DO
				REPEAT  Input.Mouse(k, u, v) UNTIL (u # x) OR (v # y) OR (k # keys);
				x := u; y := v; keys := k; M := M + keys;
				IF M = cancel THEN F.l := 0(* l *); F.t := F.pict.height (* t *) ELSE F.l:= l + (X - x) DIV F.zoom; F.t := t + (Y - y) DIV F.zoom END;
				IF smooth & (F.zoom = 1) THEN Restore(F) END;
				Oberon.DrawCursor(Oberon.Mouse, Oberon.Arrow, x, y)
			END;
			IF ~ smooth OR (F.zoom # 1) THEN Restore(F) END
		END
	ELSIF keys = {MR} THEN
		TrackSelection(F,X,Y,keys);
		GetSelection(P,time,x,y,w,h);
		IF keys = {ML,MR} THEN
			Pictures.ReplConst(F.pict,black,x, y, w,h, Display.replace); Pictures.Update(P,x,y,w,h)
		ELSIF keys = {MM,MR} THEN
			cMsg.x := x; cMsg.y := y;cMsg.w := w; cMsg.h := h; cMsg.pict := P;
			Oberon.FocusViewer.handle(Oberon.FocusViewer,cMsg)
		END
	END;
	TrackMouse(keys,X,Y)
END Edit;
PROCEDURE Handle*(F: Display.Frame; VAR msg: Display.FrameMsg);
	VAR F1 : Frame; DX, DY, H0, X, Y, x, y, w, h, dx : INTEGER; p : LONGINT;
BEGIN
	WITH F : Frame DO
		IF msg IS Oberon.ControlMsg THEN
			WITH msg : Oberon.ControlMsg DO
				IF msg.id = Oberon.defocus THEN Defocus(F)
				ELSIF msg.id = Oberon.neutralize THEN Neutralize(F)
				ELSIF msg.id = Oberon.mark THEN Oberon.DrawCursor(Oberon.Pointer, Oberon.Star, msg.X, msg.Y)
				END
			END
		ELSIF msg IS Oberon.InputMsg THEN
			WITH msg: Oberon.InputMsg DO
				IF msg.id = Oberon.consume THEN
					IF F.car > 0 THEN
						X := F.caret.x; Y :=  F.caret.y;
						Write(F,msg.fnt,color,msg.ch,X,Y, Display.paint);	(* << RC *)
						Display.GetChar(msg.fnt.raster,msg.ch,dx,x,y,w,h,p);
						Pictures.Update(F.pict,X+x-dx,Y+y,w,h);
						SetCaret(F,X,Y)
					END
				(* write *)
				ELSIF  msg.id = Oberon.track THEN
					IF msg.keys # {} THEN Edit(F,msg.X, msg.Y, msg.keys) ELSE
					Oberon.DrawCursor(Oberon.Mouse, Oberon.Arrow, msg.X, msg.Y) END
				END
			END
		ELSIF msg IS Oberon.CopyMsg THEN
			WITH msg : Oberon.CopyMsg DO
				Copy(F,F1); msg.F := F1
			END
		ELSIF msg IS MenuViewers.ModifyMsg THEN
			Neutralize(F);
			WITH msg : MenuViewers.ModifyMsg DO
				Modify(F, msg.id, msg.dY, msg.Y, msg.H)
			END
		ELSIF msg IS Oberon.CopyOverMsg THEN
			WITH msg : Oberon.CopyOverMsg DO
				IF (F.car > 0) THEN
					WriteText(F,F.caret.x,F.caret.y,msg.text,msg.beg,msg.end)
				END
			END
		ELSIF msg IS CopyOverMsg THEN
			WITH msg : CopyOverMsg DO
				CopyOver(F,msg.pict,msg.x,msg.y,msg.w,msg.h)
			END
		ELSIF msg IS SelectionMsg THEN
			WITH msg : SelectionMsg DO
				IF (F.time > msg.time) & (F.sel > 0) THEN
					msg.pict := F.pict; msg.time := F.time; msg.x := F.selx; msg.y := F.sely; msg.w := F.selw; msg.h := F.selh
				END
			END
		ELSIF msg IS UpdateMsg THEN
			WITH msg : UpdateMsg DO
				IF msg.pict = F.pict THEN
					IF msg.id= redraw THEN
						RestorePicture(F,msg.x,msg.y,msg.w,msg.h)
					ELSIF msg.id = resize THEN
						ResizePicture(F,msg.pict,msg.x,msg.y)
					END
				END
			END
		END
END Handle;
PROCEDURE Picture*(name : ARRAY OF CHAR) : Pictures.Picture;
	VAR P : Pictures.Picture;
BEGIN
	NEW(P); Pictures.Open(P, name); P.notify := NotifyDisplay; RETURN P
END Picture;
PROCEDURE Open*(F : Frame;H: Display.Handler; P : Pictures.Picture; l, t : INTEGER);
BEGIN
	F.pict := P; F.t := t; F.l := l; F.car := 0; F.zoom := 1; F.sel := 0;
	F.handle := H
END Open;
PROCEDURE NewPicture*(P : Pictures.Picture) : Frame;
	VAR F : Frame;
BEGIN
	NEW(F); Open(F,Handle,P,0,P.height); P.notify := NotifyDisplay;
	RETURN F
END NewPicture;
BEGIN
	menuString := "System.Close  System.Copy  System.Grow  Paint.Zoom  Paint.Resize  Paint.Store";
	cancel := {ML,MM,MR};
	lineWidth := 1;grid := 1; color := Display.white;
	smooth := TRUE
END PictureFrames.