protected function polygonLinearGradient(awLinearGradient $gradient, awPolygon $polygon)
{
$count = $polygon->count();
if ($count >= 4) {
$left = $polygon->get(0);
$right = $polygon->get($count - 1);
if ($gradient->angle === 0) {
// Get polygon maximum and minimum
$offset = $polygon->get(0);
$max = $min = $offset->y;
for ($i = 1; $i < $count - 1; $i++) {
$offset = $polygon->get($i);
$max = max($max, $offset->y);
$min = min($min, $offset->y);
}
$this->init($gradient, $max - $min);
$prev = $polygon->get(1);
$sum = 0;
for ($i = 2; $i < $count - 1; $i++) {
$current = $polygon->get($i);
$interval = 1;
if ($i !== $count - 2) {
$current->x -= $interval;
}
if ($current->x - $prev->x > 0) {
// Draw rectangle
$x1 = $prev->x;
$x2 = $current->x;
$y1 = max($prev->y, $current->y);
$y2 = $left->y;
$gradient = new awLinearGradient($this->color($max - $min - ($y2 - $y1)), $this->color($max - $min), 0);
if ($y1 > $y2) {
$y2 = $y1;
}
$this->driver->filledRectangle($gradient, awLine::build($x1, $y1, $x2, $y2));
$top = $prev->y < $current->y ? $current : $prev;
$bottom = $prev->y >= $current->y ? $current : $prev;
$gradient = new awLinearGradient($this->color($bottom->y - $min), $this->color($max - $min - ($y2 - $y1)), 0);
$gradientDriver = new awGDGradientDriver($this->driver);
$gradientDriver->drawFilledFlatTriangle($gradient, new awPoint($prev->x, min($prev->y, $current->y)), $top, new awPoint($current->x, min($prev->y, $current->y)));
unset($gradientDriver);
$sum += $current->x - $prev->x;
}
$prev = $current;
$prev->x += $interval;
}
} elseif ($gradient->angle === 90) {
$width = $right->x - $left->x;
$this->init($gradient, $width);
$pos = 1;
$next = $polygon->get($pos++);
$this->next($polygon, $pos, $prev, $next);
for ($i = 0; $i <= $width; $i++) {
$x = $left->x + $i;
$y1 = round($prev->y + ($next->y - $prev->y) * (($i + $left->x - $prev->x) / ($next->x - $prev->x)));
$y2 = $left->y;
// Draw line
$color = $this->color($i);
// YaPB : PHP does not handle alpha on lines
$this->driver->filledRectangle($color, awLine::build($x, $y1, $x, $y2));
unset($color);
// Jump to next point
if ($next->x == $i + $left->x) {
$this->next($polygon, $pos, $prev, $next);
}
}
}
} elseif ($count === 3) {
$this->drawFilledTriangle($gradient, $polygon);
}
}
