(*
Copyright 2021 Anton Krotov
This file is part of CEdit.
CEdit is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
CEdit is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with CEdit. If not, see <http://www.gnu.org/licenses/>.
*)
MODULE Scroll;
IMPORT G := Graph;
TYPE
tScroll* = POINTER TO RECORD
vertical, mouse: BOOLEAN;
canvas: G.tCanvas;
xSize*, ySize*, pos, mousePos: INTEGER;
color, bkColor: INTEGER;
value*, maxVal*: INTEGER
END;
PROCEDURE draw* (scroll: tScroll; x, y: INTEGER);
VAR
pos, a, b: INTEGER;
canvas: G.tCanvas;
BEGIN
IF scroll.vertical THEN
a := scroll.ySize;
b := scroll.xSize
ELSE
a := scroll.xSize;
b := scroll.ySize
END;
IF scroll.maxVal > 0 THEN
pos := (a - b)*scroll.value DIV scroll.maxVal
ELSE
pos := 0
END;
canvas := scroll.canvas;
G.SetColor(canvas, scroll.bkColor);
G.clear(canvas);
G.SetColor(canvas, 0808080H);
G.Rect(canvas, 0, 0, scroll.xSize - 1, scroll.ySize - 1);
G.SetColor(canvas, scroll.color);
DEC(b, 2);
IF scroll.vertical THEN
G.FillRect(canvas, 1, pos + 1, b, pos + b);
G.SetColor(canvas, 0404040H);
G.HLine(canvas, pos + 1 + b DIV 2, 4, b - 4);
G.HLine(canvas, pos + 1 + b DIV 2 - 3, 6, b - 6);
G.HLine(canvas, pos + 1 + b DIV 2 + 3, 6, b - 6);
ELSE
G.FillRect(canvas, pos + 1, 1, pos + b, b);
G.SetColor(canvas, 0404040H);
G.VLine(canvas, pos + b DIV 2, 4, b - 4);
G.VLine(canvas, pos + b DIV 2 - 3, 6, b - 6);
G.VLine(canvas, pos + b DIV 2 + 3, 6, b - 6);
END;
scroll.pos := pos;
G.DrawCanvas(canvas, x, y);
END draw;
PROCEDURE create* (xSize, ySize: INTEGER; color, bkColor: INTEGER): tScroll;
VAR
scroll: tScroll;
BEGIN
NEW(scroll);
scroll.xSize := xSize;
scroll.ySize := ySize;
scroll.vertical := xSize < ySize;
scroll.maxVal := 30;
scroll.value := 0;
scroll.mouse := FALSE;
scroll.bkColor := bkColor;
scroll.color := color;
scroll.canvas := G.CreateCanvas(xSize, ySize)
RETURN scroll
END create;
PROCEDURE resize* (scroll: tScroll; xSize, ySize: INTEGER);
BEGIN
scroll.xSize := xSize;
scroll.ySize := ySize;
scroll.vertical := xSize < ySize;
G.destroy(scroll.canvas);
scroll.canvas := G.CreateCanvas(xSize, ySize);
END resize;
PROCEDURE mouse* (scroll: tScroll; x, y: INTEGER);
VAR
pos, b: INTEGER;
BEGIN
IF scroll.vertical THEN
pos := y - 1;
b := scroll.xSize - 2
ELSE
pos := x - 1;
b := scroll.ySize - 2
END;
IF ~scroll.mouse THEN
scroll.mouse := TRUE;
IF (scroll.pos <= pos) & (pos <= scroll.pos + b - 1) THEN
scroll.mousePos := pos - scroll.pos
ELSE
scroll.mousePos := b DIV 2;
scroll.value := (pos - scroll.mousePos)*scroll.maxVal DIV ABS(scroll.xSize - scroll.ySize)
END
ELSE
scroll.value := (pos - scroll.mousePos)*scroll.maxVal DIV ABS(scroll.xSize - scroll.ySize)
END;
IF scroll.value < 0 THEN
scroll.value := 0
ELSIF scroll.value > scroll.maxVal THEN
scroll.value := scroll.maxVal
END
END mouse;
PROCEDURE MouseUp* (scroll: tScroll);
BEGIN
IF scroll # NIL THEN
scroll.mouse := FALSE
END
END MouseUp;
END Scroll.