lazarus/lcl/graphutil.pp
paul f703ada675 gtk, qt: improve a bit getsyscolor return
git-svn-id: trunk@14957 -
2008-04-25 07:21:19 +00:00

283 lines
7.3 KiB
ObjectPascal

{ $Id$ }
{
/***************************************************************************
graphtype.pp
------------
Graphic utility functions.
***************************************************************************/
*****************************************************************************
* *
* This file is part of the Lazarus Component Library (LCL) *
* *
* See the file COPYING.modifiedLGPL, included in this distribution, *
* for details about the copyright. *
* *
* This program 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. *
* *
*****************************************************************************
}
unit GraphUtil;
{$mode objfpc}{$H+}
interface
uses
Types, Graphics, Math, LCLType;
function ColorToGray(const AColor: TColor): Byte;
procedure ColorToHLS(const AColor: TColor; out H, L, S: Byte);
procedure RGBtoHLS(const R, G, B: Byte; out H, L, S: Byte);
function HLStoColor(const H, L, S: Byte): TColor;
procedure HLStoRGB(const H, L, S: Byte; out R, G, B: Byte);
// specific things:
{
Draw gradient from top to bottom with parabolic color grow
}
procedure DrawVerticalGradient(Canvas: TCanvas; ARect: TRect; TopColor, BottomColor: TColor);
{
Draw nice looking window with Title
}
procedure DrawGradientWindow(Canvas: TCanvas; WindowRect: TRect; TitleHeight: Integer; BaseColor: TColor);
// delphi compatibility
procedure ColorRGBToHLS(clrRGB: COLORREF; var Hue, Luminance, Saturation: Word);
function ColorHLSToRGB(Hue, Luminance, Saturation: Word): TColorRef;
function ColorAdjustLuma(clrRGB: TColor; n: Integer; fScale: BOOL): TColor;
function GetHighLightColor(const Color: TColor; Luminance: Integer = 19): TColor;
function GetShadowColor(const Color: TColor; Luminance: Integer = -50): TColor;
implementation
//TODO: Check code on endianess
procedure ExtractRGB(RGB: Cardinal; var R, G, B: Byte); inline;
begin
R := RGB and $FF;
G := (RGB shr 8) and $FF;
B := (RGB shr 16) and $FF;
end;
function ColorToGray(const AColor: TColor): Byte;
var
RGB: LongInt;
begin
if AColor = clNone
then RGB := 0
else RGB := ColorToRGB(AColor);
Result := Trunc(0.222 * (RGB and $FF) + 0.707 * ((RGB shr 8) and $FF) + 0.071 * (RGB shr 16 and $FF));
end;
procedure ColorToHLS(const AColor: TColor; out H, L, S: Byte);
var
R, G, B: Byte;
RGB: Cardinal;
begin
RGB := ColorToRGB(AColor);
ExtractRGB(RGB, R, G, B);
RGBtoHLS(R, G, B, H, L, S);
end;
function HLStoColor(const H, L, S: Byte): TColor;
var
R, G, B: Byte;
begin
HLStoRGB(H, L, S, R, G, B);
Result := R or (G shl 8) or (B shl 16);
end;
const
HUE_000 = 0;
HUE_060 = 43;
HUE_120 = 85;
HUE_180 = 128;
HUE_240 = 170;
HUE_300 = 213;
procedure RGBtoHLS(const R, G, B: Byte; out H, L, S: Byte);
var
cMax, cMin: Byte; // max and min RGB values
Rdelta, Gdelta, Bdelta: Byte; // intermediate value: % of spread from max
diff: Byte;
begin
// calculate lightness
cMax := MaxIntValue([R, G, B]);
cMin := MinIntValue([R, G, B]);
L := (cMax + cMin + 1) div 2;
diff := cMax - cMin;
if diff = 0
then begin
// r=g=b --> achromatic case
S := 0;
H := 0;
end
else begin
// chromatic case
// saturation
if L <= 128
then S := (diff * 255) div (cMax + cMin)
else S := (diff * 255) div (510 - cMax - cMin);
// hue
Rdelta := (cMax - R);
Gdelta := (cMax - G);
Bdelta := (cMax - B);
if R = cMax
then H := HUE_000 + ((Bdelta - Gdelta) * HUE_060) div diff
else if G = cMax
then H := HUE_120 + ((Rdelta - Bdelta) * HUE_060) div diff
else H := HUE_240 + ((Gdelta - Rdelta) * HUE_060) div diff;
end;
end;
procedure HLStoRGB(const H, L, S: Byte; out R, G, B: Byte);
// utility routine for HLStoRGB
function HueToRGB(const n1, n2: Byte; Hue: Integer): Byte;
begin
if Hue > 255
then Dec(Hue, 255)
else if Hue < 0
then Inc(Hue, 255);
// return r,g, or b value from this tridrant
case Hue of
HUE_000..HUE_060 - 1: Result := n1 + (n2 - n1) * Hue div HUE_060;
HUE_060..HUE_180 - 1: Result := n2;
HUE_180..HUE_240 - 1: Result := n1 + (n2 - n1) * (HUE_240 - Hue) div HUE_060;
else
Result := n1;
end;
end;
var
n1, n2: Byte;
begin
if S = 0
then begin
// achromatic case
R := L;
G := L;
B := L;
end
else begin
// chromatic case
// set up magic numbers
if L < 128
then begin
n2 := L + (L * S) div 255;
n1 := 2 * L - n2;
end
else begin
n2 := S + L - (L * S) div 255;
n1 := 2 * L - n2 - 1;
end;
// get RGB
R := HueToRGB(n1, n2, H + HUE_120);
G := HueToRGB(n1, n2, H);
B := HueToRGB(n1, n2, H - HUE_120);
end;
end;
procedure ColorRGBToHLS(clrRGB: COLORREF; var Hue, Luminance, Saturation: Word);
var
H, L, S: Byte;
begin
ColorToHLS(clrRGB, H, L, S);
Hue := H;
Luminance := L;
Saturation := S;
end;
function ColorHLSToRGB(Hue, Luminance, Saturation: Word): TColorRef;
begin
Result := HLStoColor(Hue, Luminance, Saturation);
end;
function ColorAdjustLuma(clrRGB: TColor; n: Integer; fScale: BOOL): TColor;
var
H, L, S: Byte;
begin
// what is fScale?
ColorToHLS(clrRGB, H, L, S);
Result := HLStoColor(H, L + n, S);
end;
function GetHighLightColor(const Color: TColor; Luminance: Integer): TColor;
begin
Result := ColorAdjustLuma(Color, Luminance, False);
end;
function GetShadowColor(const Color: TColor; Luminance: Integer): TColor;
begin
Result := ColorAdjustLuma(Color, Luminance, False);
end;
procedure DrawVerticalGradient(Canvas: TCanvas; ARect: TRect; TopColor, BottomColor: TColor);
var
y, h: Integer;
r1, g1, b1: byte;
r2, g2, b2: byte;
dr, dg, db: integer;
function GetColor(pos, total: integer): TColor;
function GetComponent(c1, dc: integer): integer;
begin
Result := Round(dc / sqr(total) * sqr(pos) + c1);
end;
begin
Result :=
GetComponent(r1, dr) or
(GetComponent(g1, dg) shl 8) or
(GetComponent(b1, db) shl 16);
end;
procedure CalcDeltas;
begin
ExtractRGB(TopColor, r1, g1, b1);
ExtractRGB(BottomColor, r2, g2, b2);
dr := r2 - r1;
dg := g2 - g1;
db := b2 - b1;
end;
begin
TopColor := ColorToRGB(TopColor);
BottomColor := ColorToRGB(BottomColor);
CalcDeltas;
h := ARect.Bottom - ARect.Top;
for y := ARect.Top to ARect.Bottom do
begin
Canvas.Pen.Color := GetColor(y - ARect.Top, h);
Canvas.Line(ARect.Left, y, ARect.Right, y);
end;
end;
procedure DrawGradientWindow(Canvas: TCanvas; WindowRect: TRect; TitleHeight: Integer; BaseColor: TColor);
begin
Canvas.Brush.Color := BaseColor;
Canvas.FrameRect(WindowRect);
InflateRect(WindowRect, -1, -1);
WindowRect.Bottom := WindowRect.Top + TitleHeight;
DrawVerticalGradient(Canvas, WindowRect, GetHighLightColor(BaseColor), GetShadowColor(BaseColor));
end;
end.