#include "config.h"
#include "Gradient.h"
#include "Color.h"
namespace WebCore {
Gradient::Gradient(const FloatPoint& p0, const FloatPoint& p1)
: m_radial(false)
, m_p0(p0)
, m_p1(p1)
, m_r0(0)
, m_r1(0)
, m_stopsSorted(false)
, m_lastStop(0)
, m_spreadMethod(SpreadMethodPad)
{
platformInit();
}
Gradient::Gradient(const FloatPoint& p0, float r0, const FloatPoint& p1, float r1)
: m_radial(true)
, m_p0(p0)
, m_p1(p1)
, m_r0(r0)
, m_r1(r1)
, m_stopsSorted(false)
, m_lastStop(0)
, m_spreadMethod(SpreadMethodPad)
{
platformInit();
}
Gradient::~Gradient()
{
platformDestroy();
}
void Gradient::addColorStop(float value, const Color& color)
{
float r;
float g;
float b;
float a;
color.getRGBA(r, g, b, a);
m_stops.append(ColorStop(value, r, g, b, a));
m_stopsSorted = false;
platformDestroy();
}
static inline bool compareStops(const Gradient::ColorStop& a, const Gradient::ColorStop& b)
{
return a.stop < b.stop;
}
void Gradient::getColor(float value, float* r, float* g, float* b, float* a) const
{
ASSERT(value >= 0);
ASSERT(value <= 1);
if (m_stops.isEmpty()) {
*r = 0;
*g = 0;
*b = 0;
*a = 0;
return;
}
if (!m_stopsSorted) {
if (m_stops.size())
std::stable_sort(m_stops.begin(), m_stops.end(), compareStops);
m_stopsSorted = true;
}
if (value <= 0 || value <= m_stops.first().stop) {
*r = m_stops.first().red;
*g = m_stops.first().green;
*b = m_stops.first().blue;
*a = m_stops.first().alpha;
return;
}
if (value >= 1 || value >= m_stops.last().stop) {
*r = m_stops.last().red;
*g = m_stops.last().green;
*b = m_stops.last().blue;
*a = m_stops.last().alpha;
return;
}
int stop = findStop(value);
const ColorStop& lastStop = m_stops[stop];
const ColorStop& nextStop = m_stops[stop + 1];
float stopFraction = (value - lastStop.stop) / (nextStop.stop - lastStop.stop);
*r = lastStop.red + (nextStop.red - lastStop.red) * stopFraction;
*g = lastStop.green + (nextStop.green - lastStop.green) * stopFraction;
*b = lastStop.blue + (nextStop.blue - lastStop.blue) * stopFraction;
*a = lastStop.alpha + (nextStop.alpha - lastStop.alpha) * stopFraction;
}
int Gradient::findStop(float value) const
{
ASSERT(value >= 0);
ASSERT(value <= 1);
ASSERT(m_stopsSorted);
int numStops = m_stops.size();
ASSERT(numStops >= 2);
ASSERT(m_lastStop < numStops - 1);
int i = m_lastStop;
if (value < m_stops[i].stop)
i = 1;
else
i = m_lastStop + 1;
for (; i < numStops - 1; ++i)
if (value < m_stops[i].stop)
break;
m_lastStop = i - 1;
return m_lastStop;
}
void Gradient::setSpreadMethod(GradientSpreadMethod spreadMethod)
{
ASSERT(m_gradient == 0);
m_spreadMethod = spreadMethod;
}
}