Thread: Graphics.h [ Canvas class ]

update :
renaming to Canvas.h
splitting into .h and .cpp

Canvas.h

Code:

//bluatigro 29 dec 2016
//Canvas.h
//win32 graphics class
#include <windows.h> #ifndef CANVAS_H
#define CANVAS_H
class Canvas
{
public :
  HDC hdc ;
  Canvas(){}
  ~Canvas(){}
  void ellipse( 
    int mx , int my , int dx , int dy ,
    int clrin , int clrout , int thick , bool center = false ) ;
  void line( 
    int x1 , int y1 , int x2 , int y2 ,
    int clr , int thick ) ;
  void triangle( 
    int x1 , int y1 , int x2 , int y2 , int x3 , int y3 ,
    int clrin , int clrout , int thick ) ;
  void rectangle( 
    int left , int top , int right , int bottom ,
    int clrin , int clrout , int thick , bool center = false ) ;
} ;
Canvas canvas ;
// primary colors
const int BLACK   = 0x000000 ;
const int RED     = 0x0000ff ;
const int GREEN   = 0x00ff00 ;
const int YELLOW  = 0x00ffff ;
const int BLUE    = 0xff0000 ;
const int MAGENTA = 0xff00ff ;
const int CYAN    = 0xffff00 ;
const int WHITE   = 0xffffff ;
//  mixed colors
const int PINK    = 0x7f7fff ;
const int ORANGE  = 0x007fff ;
const int PURPLE  = 0x7f007f ;
const int GRAY    = 0x7f7f7f ;
  
int colorMix( int clr1 , float f , int clr2 ) ;
#endif

Canvas.cpp

Code:

/
//bluatigro 29 dec 2016
//Canvas.cpp
//win32 graphics class#include "Canvas.h"
  void Canvas::ellipse( 
    int mx , int my , int dx , int dy ,
    int clrin , int clrout , int thick , bool center )
  {
    HPEN newpen = CreatePen( PS_SOLID , thick , clrout ) ;
    HBRUSH newbrush = CreateSolidBrush( clrin ) ;
    HPEN oldpen = (HPEN) SelectObject( hdc , newpen ) ;
    HBRUSH oldbrush = (HBRUSH) SelectObject( hdc , newbrush ) ;
    if ( center ) 
    {
      Ellipse( hdc , mx - dx / 2 , my - dy / 2
        , mx + dx / 2 , my + dy / 2 ) ;
    }
    else
      Ellipse( hdc , mx , my , dx , dy ) ;
    SelectObject( hdc, oldpen ) ;
    SelectObject( hdc, oldbrush ) ;
    DeleteObject( newpen ) ;
    DeleteObject( newbrush ) ;
  }
  void Canvas::line( 
    int x1 , int y1 , int x2 , int y2 ,
    int clr , int thick )
  {
    HPEN newpen = CreatePen( PS_SOLID , thick , clr ) ;
    HPEN oldpen = (HPEN)SelectObject( hdc , newpen ) ;
    MoveTo( hdc , x1 , y1 , NULL ) ;
    LineTo( hdc , x2 , y2 ) ;
    SelectObject( hdc , oldpen ) ;
    DeleteObject( newpen ) ;
  }
  void Canvas::triangle( 
    int x1 , int y1 , int x2 , int y2 , int x3 , int y3 ,
    int clrin , int clrout , int thick )
  {
    HPEN newpen = CreatePen( PS_SOLID , thick , clrout ) ;
    HBRUSH newbrush = CreateSolidBrush( clrin ) ;
    HPEN oldpen = (HPEN) SelectObject( hdc , newpen ) ;
    HBRUSH oldbrush = (HBRUSH) SelectObject( hdc , newbrush ) ;
    POINT p[] = { { x1 , y1 } , 
                  { x2 , y2 } , 
                  { x3 , y3 } } ;
  
    Polygon( hdc , p , 3 ) ;
    SelectObject( hdc, oldpen ) ;
    SelectObject( hdc, oldbrush ) ;
    DeleteObject( newpen ) ;
    DeleteObject( newbrush ) ;
  }
  void rectangle(
    int x1 , int y1 , int x2 , int y2 ,
    int clrin , int clrout , int thick , bool center )
  {
    HPEN newpen = CreatePen( PS_SOLID , thick , clrout ) ;
    HBRUSH newbrush = CreateSolidBrush( clrin ) ;
    HPEN oldpen = (HPEN) SelectObject( hdc , newpen ) ;
    HBRUSH oldbrush = (HBRUSH) SelectObject( hdc , newbrush ) ;
    if ( center )
      Rectangle( hdc , x1 - x2 / 2 , y1 - y2 / 2 , x1 + x2 / 2 , y1 + y2 / 2 ) ;
    else
      Rectangle( hdc , x1 , y1 , x2 , y2 ) ;
    SelectObject( hdc, oldpen ) ;
    SelectObject( hdc, oldbrush ) ;
    DeleteObject( newpen ) ;
    DeleteObject( newbrush ) ;
  }
int colorMix( int clr1 , float f , int clr2 )
{
  int r1 , g1 , b1 , r2 , g2 , b2 ;
  r1 = clr1 & 0xff ;
  g1 = ( clr1 >> 8 ) & 0xff ;
  b1 = ( clr1 >> 16 ) & 0xff ;
  r2 = clr2 & 0xff ;
  g2 = ( clr2 >> 8 ) & 0xff ;
  b2 = ( clr2 >> 16 ) & 0xff ;
  r1 = r1 + ( r2 - r1 ) * f ;
  g1 = g1 + ( g2 - g1 ) * f ;
  b1 = b1 + ( b2 - b1 ) * f ;
  return r1 + g1 * 0x100 + b1 * 0x10000 ; 
}