Introduction

One big framework's handicap is the low number of visual 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 the html 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 and intuitive solution,so I build this ColorPicker.This contol allow to select a color faster than the previos way.Because I haven't seen a 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:

ColorPickers (namespace Fuliggine.ColorPickers)
StableColorPicker	Is a circolar color picker it allow to select a single color.
SquareColorPicker	Is a control that ,given a base color show and allow to select it's tones.
ColorBar	Is a control that show and allow to select all base color derived from rgb except white and black.
FullColorBar	Is a control that show and allow to select all base color derived from rgb (also white and black).
ColorViewers (namespace Fuliggine.ColorPickers)
MonoFrameColor	Is a control with frame that show the selected color.
DoubleFrameColor	Is a control with two frame that show the two selected colors.
ColorGradient	Is a control that show all tones of a given color;
Special Pointers (namespace Fuliggine.ColorPickers)
HolePointer	Is the pointer that select the color in the controls.

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 allows all the possibles combination of R,G,B.After that I find the step of color done in 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<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 for who always use the HTML language.That application show a way to use the StableColorPicker.

Sample Image - ColorPicker.jpg

How to Know the RGB color

I have decided to do a round rainbow.The main problem is that in a RGB sistem we have 3 variables and in the plain there 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 point on 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 is shown 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...I call 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).