(*
Copyright 2021-2023 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, K := KolibriOS, U := Utils;
CONST
DELAY = 40;
TYPE
tProcedure = PROCEDURE;
tScroll* = RECORD
vertical, mouse: BOOLEAN;
top*, left*,
width*, height*: INTEGER; (* read only *)
btnSize, sliderSize: INTEGER;
pos, Slider, pos0, maxVal*, value*: INTEGER;
canvas: G.tCanvas;
change: tProcedure;
delay: INTEGER;
btn*: INTEGER
END;
PROCEDURE MouseUp (VAR scroll: tScroll);
BEGIN
scroll.Slider := -1;
scroll.btn := 0;
scroll.mouse := FALSE;
scroll.delay := DELAY
END MouseUp;
PROCEDURE create* (vertical: BOOLEAN; width, height: INTEGER; btnSize, sliderSize: INTEGER; change: tProcedure; VAR scroll: tScroll);
VAR
res: tScroll;
BEGIN
MouseUp(res);
res.vertical := vertical;
res.left := 0;
res.top := 0;
res.width := width;
res.height := height;
res.btnSize := btnSize;
res.sliderSize := sliderSize;
res.pos := 0;
res.maxVal := 0;
res.canvas := G.CreateCanvas(width, height);
res.change := change;
scroll := res
END create;
PROCEDURE Rect (canvas: G.tCanvas; left, top, right, bottom: INTEGER);
BEGIN
G.FillRect(canvas, left, top, right, bottom);
G.SetColor(canvas, K.colors.line);
G.Rect(canvas, left, top, right, bottom);
END Rect;
PROCEDURE _draw (scroll: tScroll);
VAR
canvas: G.tCanvas;
x, y, d, x1, x2, y1, y2,
width, height, btn: INTEGER;
PROCEDURE SetColor (canvas: G.tCanvas; c: BOOLEAN);
VAR
color: INTEGER;
BEGIN
IF c THEN
color := K.colors.button
ELSE
color := K.colors.button_text
END;
G.SetColor(canvas, color)
END SetColor;
BEGIN
btn := scroll.btnSize;
width := scroll.width;
height := scroll.height;
canvas := scroll.canvas;
G.SetColor(canvas, K.colors.light);
G.clear(canvas);
G.SetColor(canvas, K.colors.line);
G.Rect(canvas, 0, 0, width - 1, height - 1);
SetColor(canvas, scroll.btn # -1);
IF scroll.vertical THEN
Rect(canvas, 0, 0, width - 1, btn - 1);
SetColor(canvas, scroll.btn # 1);
Rect(canvas, 0, height - btn, width - 1, height - 1);
G.SetColor(canvas, K.colors.button);
Rect(canvas, 0, btn + scroll.pos - 1, width - 1, btn + scroll.pos + scroll.sliderSize - 1);
G.SetColor(canvas, K.colors.button_text);
y := btn + scroll.pos + scroll.sliderSize DIV 2 - 1;
G.HLine(canvas, y, width DIV 4, 3*width DIV 4);
G.HLine(canvas, y - 3, width DIV 3, 2*width DIV 3);
G.HLine(canvas, y + 3, width DIV 3, 2*width DIV 3);
d := 4*width DIV 10;
x1 := (width - d) DIV 2;
x2 := x1 + d;
SetColor(canvas, scroll.btn = -1);
y := (btn - d DIV 2) DIV 2 + d DIV 2 - 1;
G.Triangle(canvas, x1 - 1, y, x2, y, G.triUp);
SetColor(canvas, scroll.btn = 1);
y := y + height - btn - d DIV 2 + 1;
G.Triangle(canvas, x1 - 1, y, x2, y, G.triDown);
ELSE
Rect(canvas, 0, 0, btn - 1, height - 1);
SetColor(canvas, scroll.btn # 1);
Rect(canvas, width - btn, 0, width - 1, height - 1);
G.SetColor(canvas, K.colors.button);
Rect(canvas, btn + scroll.pos - 1, 0, btn + scroll.pos + scroll.sliderSize - 1, height - 1);
G.SetColor(canvas, K.colors.button_text);
x := btn + scroll.pos + scroll.sliderSize DIV 2 - 1;
G.VLine(canvas, x, height DIV 4, 3*height DIV 4);
G.VLine(canvas, x - 3, height DIV 3, 2*height DIV 3);
G.VLine(canvas, x + 3, height DIV 3, 2*height DIV 3);
d := 4*height DIV 10;
y1 := (height - d) DIV 2;
y2 := y1 + d;
SetColor(canvas, scroll.btn = -1);
x := (btn - d DIV 2) DIV 2 + d DIV 2 - 1;
G.Triangle(canvas, x, y1 - 1, x, y2, G.triLeft);
SetColor(canvas, scroll.btn = 1);
x := x + width - btn - d DIV 2 + 1;
G.Triangle(canvas, x, y1 - 1, x, y2, G.triRight);
END;
G.DrawCanvas(scroll.canvas, scroll.left, scroll.top)
END _draw;
PROCEDURE draw* (scroll: tScroll);
BEGIN
IF scroll.canvas # NIL THEN
_draw(scroll)
END
END draw;
PROCEDURE resize* (VAR scroll: tScroll; width, height: INTEGER);
BEGIN
G.destroy(scroll.canvas);
scroll.canvas := G.CreateCanvas(width, height);
scroll.width := width;
scroll.height := height;
draw(scroll)
END resize;
PROCEDURE setValue* (VAR scroll: tScroll; value: INTEGER);
VAR
pos, maxPos, maxVal, n, m: INTEGER;
BEGIN
maxVal := scroll.maxVal;
IF scroll.vertical THEN
maxPos := scroll.height
ELSE
maxPos := scroll.width
END;
maxPos := maxPos - scroll.btnSize*2 - scroll.sliderSize + 1;
IF (value < 0) OR (maxVal <= 0) THEN
value := 0;
pos := 0
ELSIF value > maxVal THEN
value := maxVal;
pos := maxPos
ELSE
IF (maxPos + 1) >= maxVal THEN
n := (maxPos + 1) DIV maxVal;
m := (maxPos + 1) MOD maxVal;
pos := value*n + MIN(value, m)
ELSE
pos := FLOOR(FLT(value)*FLT(maxPos + 1)/FLT(maxVal))
END;
IF pos > maxPos THEN
pos := maxPos;
value := maxVal
END
END;
scroll.pos := pos;
scroll.value := value
END setValue;
PROCEDURE ceil (p, q: INTEGER): INTEGER;
RETURN p DIV q + ORD(p MOD q # 0)
END ceil;
PROCEDURE setPos (VAR scroll: tScroll; pos: INTEGER);
VAR
maxPos, value, maxVal, n, m, x, x0, q: INTEGER;
BEGIN
maxVal := scroll.maxVal;
IF maxVal > 0 THEN
IF scroll.vertical THEN
maxPos := scroll.height
ELSE
maxPos := scroll.width
END;
maxPos := maxPos - scroll.btnSize*2 - scroll.sliderSize + 1;
IF pos <= 0 THEN
pos := 0;
value := 0
ELSIF pos >= maxPos THEN
pos := maxPos;
value := maxVal
ELSE
IF maxVal <= maxPos + 1 THEN
n := (maxPos + 1) DIV maxVal;
m := (maxPos + 1) MOD maxVal;
q := m*(n + 1);
IF q < pos THEN
value := ceil(pos - m, n)
ELSIF q > pos THEN
value := ceil(pos, n + 1)
ELSE
value := m
END;
x := value*n + MIN(value, m);
x0 := (value - 1)*n + MIN(value - 1, m);
IF x - pos > pos - x0 THEN
pos := x0;
DEC(value)
ELSE
pos := x;
IF pos > maxPos THEN
pos := maxPos;
value := maxVal
END
END
ELSE
value := FLOOR(FLT(maxVal)*FLT(pos)/FLT(maxPos + 1))
END
END
ELSE
pos := 0;
value := 0
END;
scroll.pos := pos;
scroll.value := value
END setPos;
PROCEDURE MouseMove (VAR scroll: tScroll; x, y: INTEGER);
VAR
c: INTEGER;
BEGIN
IF scroll.vertical THEN
c := y - scroll.top
ELSE
c := x - scroll.left
END;
setPos(scroll, scroll.pos0 + c - scroll.Slider);
draw(scroll)
END MouseMove;
PROCEDURE button (VAR scroll: tScroll);
VAR
btn: INTEGER;
BEGIN
WHILE scroll.btn # 0 DO
btn := scroll.btn;
setValue(scroll, scroll.value + btn);
draw(scroll);
IF scroll.change # NIL THEN
scroll.change
END;
scroll.btn := 0;
IF 0 IN K.MouseState() THEN
WHILE (0 IN K.MouseState()) & (scroll.delay > 0) DO
K.Pause(1);
DEC(scroll.delay)
END;
IF scroll.delay = 0 THEN
scroll.btn := btn;
scroll.delay := 3
ELSE
scroll.delay := DELAY
END
ELSE
scroll.delay := DELAY
END
END
END button;
PROCEDURE MouseDown (VAR scroll: tScroll; x, y: INTEGER);
VAR
c, size: INTEGER;
BEGIN
DEC(x, scroll.left);
DEC(y, scroll.top);
scroll.mouse := TRUE;
IF U.between(1, x, scroll.width - 2) & U.between(1, y, scroll.height - 2) THEN
IF scroll.vertical THEN
c := y;
size := scroll.height
ELSE
c := x;
size := scroll.width
END;
IF U.between(scroll.btnSize + scroll.pos - 1, c, scroll.btnSize + scroll.pos + scroll.sliderSize - 1) THEN
scroll.pos0 := scroll.pos;
scroll.Slider := c
ELSIF U.between(0, c, scroll.btnSize - 1) THEN
scroll.btn := -1
ELSIF U.between(size - scroll.btnSize, c, size - 1) THEN
scroll.btn := 1
ELSE
setPos(scroll, c - scroll.btnSize - scroll.sliderSize DIV 2);
scroll.pos0 := scroll.pos;
scroll.Slider := c;
draw(scroll)
END
END
END MouseDown;
PROCEDURE mouse* (VAR scroll: tScroll);
VAR
msState: SET;
x, y: INTEGER;
BEGIN
K.mouse(msState, x, y);
IF 0 IN msState THEN
IF ~scroll.mouse THEN
MouseDown(scroll, x, y)
ELSIF scroll.Slider # -1 THEN
MouseMove(scroll, x, y)
END
ELSIF scroll.mouse THEN
MouseUp(scroll);
draw(scroll)
END;
button(scroll)
END mouse;
END Scroll.