Generate and draw a fractal tree.
To draw a fractal tree is simple:
- Draw the trunk
- At the end of the trunk, split by some angle and draw two branches
- Repeat at the end of each branch until a sufficient level of branching is reached
#include <windows.h> #include <string> #include <math.h> //-------------------------------------------------------------------------------------------------- using namespace std; //-------------------------------------------------------------------------------------------------- const float PI = 3.1415926536f; //-------------------------------------------------------------------------------------------------- class myBitmap { public: myBitmap() : pen( NULL ) {} ~myBitmap() { DeleteObject( pen ); DeleteDC( hdc ); DeleteObject( bmp ); } bool create( int w, int h ) { BITMAPINFO bi; void *pBits; ZeroMemory( &bi, sizeof( bi ) ); bi.bmiHeader.biSize = sizeof( bi.bmiHeader ); bi.bmiHeader.biBitCount = sizeof( DWORD ) * 8; bi.bmiHeader.biCompression = BI_RGB; bi.bmiHeader.biPlanes = 1; bi.bmiHeader.biWidth = w; bi.bmiHeader.biHeight = -h; HDC dc = GetDC( GetConsoleWindow() ); bmp = CreateDIBSection( dc, &bi, DIB_RGB_COLORS, &pBits, NULL, 0 ); if( !bmp ) return false; hdc = CreateCompatibleDC( dc ); SelectObject( hdc, bmp ); ReleaseDC( GetConsoleWindow(), dc ); width = w; height = h; return true; } void setPenColor( DWORD clr ) { if( pen ) DeleteObject( pen ); pen = CreatePen( PS_SOLID, 1, clr ); SelectObject( hdc, pen ); } void saveBitmap( string path ) { BITMAPFILEHEADER fileheader; BITMAPINFO infoheader; BITMAP bitmap; DWORD* dwpBits; DWORD wb; HANDLE file; GetObject( bmp, sizeof( bitmap ), &bitmap ); dwpBits = new DWORD[bitmap.bmWidth * bitmap.bmHeight]; ZeroMemory( dwpBits, bitmap.bmWidth * bitmap.bmHeight * sizeof( DWORD ) ); ZeroMemory( &infoheader, sizeof( BITMAPINFO ) ); ZeroMemory( &fileheader, sizeof( BITMAPFILEHEADER ) ); infoheader.bmiHeader.biBitCount = sizeof( DWORD ) * 8; infoheader.bmiHeader.biCompression = BI_RGB; infoheader.bmiHeader.biPlanes = 1; infoheader.bmiHeader.biSize = sizeof( infoheader.bmiHeader ); infoheader.bmiHeader.biHeight = bitmap.bmHeight; infoheader.bmiHeader.biWidth = bitmap.bmWidth; infoheader.bmiHeader.biSizeImage = bitmap.bmWidth * bitmap.bmHeight * sizeof( DWORD ); fileheader.bfType = 0x4D42; fileheader.bfOffBits = sizeof( infoheader.bmiHeader ) + sizeof( BITMAPFILEHEADER ); fileheader.bfSize = fileheader.bfOffBits + infoheader.bmiHeader.biSizeImage; GetDIBits( hdc, bmp, 0, height, ( LPVOID )dwpBits, &infoheader, DIB_RGB_COLORS ); file = CreateFile( path.c_str(), GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL ); WriteFile( file, &fileheader, sizeof( BITMAPFILEHEADER ), &wb, NULL ); WriteFile( file, &infoheader.bmiHeader, sizeof( infoheader.bmiHeader ), &wb, NULL ); WriteFile( file, dwpBits, bitmap.bmWidth * bitmap.bmHeight * 4, &wb, NULL ); CloseHandle( file ); delete [] dwpBits; } HDC getDC() { return hdc; } int getWidth() { return width; } int getHeight() { return height; } private: HBITMAP bmp; HDC hdc; HPEN pen; int width, height; }; //-------------------------------------------------------------------------------------------------- class vector2 { public: vector2() { x = y = 0; } vector2( int a, int b ) { x = a; y = b; } void set( int a, int b ) { x = a; y = b; } void rotate( float angle_r ) { float _x = static_cast<float>( x ), _y = static_cast<float>( y ), s = sinf( angle_r ), c = cosf( angle_r ), a = _x * c - _y * s, b = _x * s + _y * c; x = static_cast<int>( a ); y = static_cast<int>( b ); } int x, y; }; //-------------------------------------------------------------------------------------------------- class fractalTree { public: fractalTree() { _ang = DegToRadian( 24.0f ); } float DegToRadian( float degree ) { return degree * ( PI / 180.0f ); } void create( myBitmap* bmp ) { _bmp = bmp; float line_len = 130.0f; vector2 sp( _bmp->getWidth() / 2, _bmp->getHeight() - 1 ); MoveToEx( _bmp->getDC(), sp.x, sp.y, NULL ); sp.y -= static_cast<int>( line_len ); LineTo( _bmp->getDC(), sp.x, sp.y); drawRL( &sp, line_len, 0, true ); drawRL( &sp, line_len, 0, false ); } private: void drawRL( vector2* sp, float line_len, float a, bool rg ) { line_len *= .75f; if( line_len < 2.0f ) return; MoveToEx( _bmp->getDC(), sp->x, sp->y, NULL ); vector2 r( 0, static_cast<int>( line_len ) ); if( rg ) a -= _ang; else a += _ang; r.rotate( a ); r.x += sp->x; r.y = sp->y - r.y; LineTo( _bmp->getDC(), r.x, r.y ); drawRL( &r, line_len, a, true ); drawRL( &r, line_len, a, false ); } myBitmap* _bmp; float _ang; }; //-------------------------------------------------------------------------------------------------- int main( int argc, char* argv[] ) { ShowWindow( GetConsoleWindow(), SW_MAXIMIZE ); myBitmap bmp; bmp.create( 640, 512 ); bmp.setPenColor( RGB( 255, 255, 0 ) ); fractalTree tree; tree.create( &bmp ); BitBlt( GetDC( GetConsoleWindow() ), 0, 20, 648, 512, bmp.getDC(), 0, 0, SRCCOPY ); bmp.saveBitmap( "f://rc//fracTree.bmp" ); system( "pause" ); return 0; } //--------------------------------------------------------------------------------------------------
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