Introduction

One big framework's handicap is the low number ofvisual controls.Luckly the most usefull are yet present ,but often we find some problem with the less common control.Some days ago I make a program that translate the colors in thehtml code.In the first I used simply three trackbar to change the red,green and blue.In a second moment I need to put a more quick andintuitive solution,so I build this ColorPicker.This contol allow toselect a color faster than the previos way.Because I haven't seena similar control in this section ,I decide to post it.
In the last update I add a consistent number of controls.AllControls are listed below:

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The ColorPickers Controls

The most part of thoose controls dont need any word,almost i think.For CodeBar and full code bar I divide the width in some section to allowsall the possibles combination of R,G,B.After that I find the step of color donein every pixel an draw the control line by line…

protected override void OnPaint(PaintEventArgs e)
{ int R=255;
int G=0;
int B=0;
//orizzontal…

int colorstep=255/ ( this.Width/6 );
int i=0;
//the color step x pixel

for(B=0;B<256;B+=colorstep ,i++)
{
e.Graphics.DrawLine(new Pen(new SolidBrush(Color.FromArgb(R,G,B)),1),i,0,i,this.Height);

}
B=255;
for(R=255;R>0;R-=colorstep,i++)
{

e.Graphics.DrawLine(new Pen(new SolidBrush(Color.FromArgb(R,G,B)),1),i,0,i,this.Height);

}
R=0;
for(G=0;G<256;G+=colorstep,i++)
{
e.Graphics.DrawLine(new Pen(new SolidBrush(Color.FromArgb(R,G,B)),1),i,0,i,this.Height);

}
G=255;

for(B=255;B>0;B-=colorstep,i++)
{
e.Graphics.DrawLine(new Pen(new SolidBrush(Color.FromArgb(R,G,B)),1),i,0,i,this.Height);

}

B=0;

for(R=0;R<256;R+=colorstep,i++)
{
e.Graphics.DrawLine(new Pen(new SolidBrush(Color.FromArgb(R,G,B)),1),i,0,i,this.Height);

}
R=255;
B=0;
for(G=255;G>0;G-=colorstep,i++)
{
e.Graphics.DrawLine(new Pen(new SolidBrush(Color.FromArgb(R,G,B)),1),i,0,i,this.Height);

}

}

A similar way is used also in the Color Gradient and SquareColorPicker,but there only the tones of the color are shown.

protected override void OnPaint(PaintEventArgs e)
{int ScaleY=255/this.Height;

for ( int y = 0 ; y<this.Height;y++)
{
int r=pColor.R-(y*ScaleY);
if(r<0)
{
r=0;
}

int g=pColor.G-(y*ScaleY);
if

(g< pan class="cpp-literal">0)
{
g=0;
}

int b=pColor.B-(y*ScaleY);
if(b<0)
{
b=0;
}
e.Graphics.DrawLine(new Pen(new SolidBrush(Color.FromArgb(r,g,b)),1),0,y,this.Width,y);
}
}

The Mono and Double Fame Color are realized by simple panels .The Hole pointer is a simple control that bring itself in the aprent bounds when them mouse brag it.Basing on its position controls decide what's the selected color.

The Color Picker Application

The demo is that I find a nice application,tin and simple but usefull forwho always use the HTML language.That application show a way to use the StableColorPicker.

How to Know the RGB color

I have decided to do a round rainbow.The main problem isthat in a RGB sistem we have 3 variables and in the plainthere are only two.So I decide to take the x value as Red,Y value as Green and the distance from center as Blue.The circle is inscripted in a square of 255 pixel for each side.The distance from the center are calculated with the Pitagora's Theorema and resized to fit in the range 0-255.So at every point are associed one tern of value beethwin 0 and 255.

How to paint the circle

To paint the circle,I have two Ways:the first one is to paint all the pointon the ray ,for each angle;the second one is to paint every point in a circle each circle .This two different way can be selected by the user .This piece of code isshown here:

protected override void OnPaint(PaintEventArgs e)
{
//set some usefull var

int offsett= 1;
int width=this.ClientRectangle.Width-2;
int height=this.ClientRectangle.Height-2;
int rx= width/2;
int x=10;
int y=10;
int cx=offsett+rx;
double teta=0 ;
//refresh the background

e .Graphics.FillRectangle(new SolidBrush(this.BackColor),this.ClientRectangle);

//The core of painting
if ( AnimationRadial==true)
{
for ( teta = 0 ; teta <2*Math.PI; teta=teta + 0.003)
{for ( double ray = 0 ; ray<rx ;ray= ray+1)
{

x= cx+ Convert.ToInt32(ray* Math.Cos(teta));
y= cx – Convert.ToInt32(ray* Math.Sin(teta));
Rectangle rect= new Rectangle(x,y,1,1);

e.Graphics.FillRectangle(new SolidBrush(Color.FromArgb(x,y,(int)(ray/rx*255))),rect);

}}}
else

{
for ( double ray = 0 ; ray<rx ;ray= ray+1)
{
for ( teta = 0 ; teta <2*Math.PI; teta=teta + 0.003)
{
x= cx+ Convert.ToInt32(ray* Math.Cos(teta));
y= cx – Convert.ToInt32(ray* Math.Sin(teta));
Rectangle rect= new Rectangle(x,y,1,1);
e.Graphics.FillRectangle(new SolidBrush(Color.FromArgb(x,y,(int)(ray/rx*255))),rect);
}}}}protected override void OnPaint(PaintEventArgs e)
{
//set some usefull var

int offsett= 1;
int width=this.ClientRectangle.Width-2;
int height=this.ClientRectangle.Height-2;
int rx= width/2;
int x=10;
int y=10;
int cx=offsett+rx;
double teta=0 ;
//refresh the background

e .Graphics.FillRectangle(new SolidBrush(this.BackColor),this.ClientRectangle);

//The core of painting
if ( AnimationRadial==true)
{
for ( teta = 0 ; teta <2*Math.PI; teta=teta + 0.003)
{for ( double ray = 0 ; ray<rx ;ray= ray+1)
{

x= cx+ Convert.ToInt32(ray* Math.Cos(teta));
y= cx – Convert.ToInt32(ray* Math.Sin(teta));
Rectangle rect= new Rectangle(x,y,1,1);

e.Graphics.FillRectangle(new SolidBrush(Color.FromArgb(x,y,(int)(ray/rx*255))),rect);

}}}
else

{
for ( double ray = 0 ; ray<rx ;ray= ray+1)
{
for ( teta = 0 ; teta <2*Math.PI; teta=teta + 0.003)
{
x= cx+ Convert.ToInt32(ray* Math.Cos(teta));
y= cx – Convert.ToInt32(ray* Math.Sin(teta));
Rectangle rect= new Rectangle(x,y,1,1);
e.Graphics.FillRectangle(new SolidBrush(Color.FromArgb(x,y,(int)(ray/rx*255))),rect);
}}}}

How to select a color

To select a color I made a special class that can be moved by the user.Every Color Picher has one of this and the cpntol return the color under it.

Problems

A big problem is the flikkerous repainting .I resolve taking the screenshoot of this control,and putting it on a new control derived from paintbox.This isn't an elegant solution but works…Icall this new control StableColorPicker

Classes

In this relase there are the first version of the control(ColorPicker) who work fine,but isn't very stable,and the second stable version(StableColorPicker).