haiku/headers/libs/agg/agg_gray8.h
DarkWyrm abd0030237 Sync to AGG tree to support stippi's Painter classes
git-svn-id: file:///srv/svn/repos/haiku/trunk/current@10693 a95241bf-73f2-0310-859d-f6bbb57e9c96
2005-01-12 11:05:58 +00:00

109 lines
3.2 KiB
C++
Executable File

//----------------------------------------------------------------------------
// Anti-Grain Geometry - Version 2.2
// Copyright (C) 2002-2004 Maxim Shemanarev (http://www.antigrain.com)
//
// Permission to copy, use, modify, sell and distribute this software
// is granted provided this copyright notice appears in all copies.
// This software is provided "as is" without express or implied
// warranty, and with no claim as to its suitability for any purpose.
//
//----------------------------------------------------------------------------
// Contact: mcseem@antigrain.com
// mcseemagg@yahoo.com
// http://www.antigrain.com
//----------------------------------------------------------------------------
//
// color type gray8
//
//----------------------------------------------------------------------------
#ifndef AGG_GRAY8_INCLUDED
#define AGG_GRAY8_INCLUDED
#include "agg_basics.h"
#include "agg_color_rgba.h"
#include "agg_color_rgba8.h"
namespace agg
{
//===================================================================gray8
struct gray8
{
typedef int8u alpha_type;
int8u v;
int8u a;
//--------------------------------------------------------------------
gray8() {}
//--------------------------------------------------------------------
gray8(unsigned v_, unsigned a_=255) :
v(int8u(v_)), a(int8u(a_)) {}
//--------------------------------------------------------------------
gray8(const rgba& c) :
v(int8u((0.299*c.r + 0.587*c.g + 0.114*c.b) * 255.0 + 0.5)),
a(int8u(c.a*255.0)) {}
//--------------------------------------------------------------------
gray8(const rgba8& c) :
v((c.r*77 + c.g*150 + c.b*29) >> 8),
a(c.a) {}
//--------------------------------------------------------------------
void clear()
{
v = a = 0;
}
//--------------------------------------------------------------------
const gray8& transparent()
{
a = 0;
return *this;
}
//--------------------------------------------------------------------
void opacity(double a_)
{
if(a_ < 0.0) a_ = 0.0;
if(a_ > 1.0) a_ = 1.0;
a = int8u(a_ * 255.0);
}
//--------------------------------------------------------------------
double opacity() const
{
return double(a) / 255.0;
}
//--------------------------------------------------------------------
gray8 gradient(gray8 c, double k) const
{
gray8 ret;
int ik = int(k * 256);
ret.v = int8u(int(v) + (((int(c.v) - int(v)) * ik) >> 8));
ret.a = int8u(int(a) + (((int(c.a) - int(a)) * ik) >> 8));
return ret;
}
//--------------------------------------------------------------------
gray8 pre() const
{
return gray8((v*a) >> 8, a);
}
//--------------------------------------------------------------------
static gray8 no_color() { return gray8(0,0); }
};
}
#endif