// rasterizes a geometry.
void rasterize(const Geometry* geometry, const osg::Vec4& color, RenderFrame& frame,
agg::rasterizer& ras, agg::renderer<agg::span_abgr32>& ren)
{
osg::Vec4 c = color;
unsigned int a = (unsigned int)(127+(c.a()*255)/2); // scale alpha up
agg::rgba8 fgColor( (unsigned int)(c.r()*255), (unsigned int)(c.g()*255), (unsigned int)(c.b()*255), a );
ras.filling_rule( agg::fill_even_odd );
ConstGeometryIterator gi( geometry );
while( gi.hasMore() )
{
c = color;
const Geometry* g = gi.next();
for( Geometry::const_iterator p = g->begin(); p != g->end(); p++ )
{
const osg::Vec3d& p0 = *p;
double x0 = frame.xf*(p0.x()-frame.xmin);
double y0 = frame.yf*(p0.y()-frame.ymin);
if ( p == g->begin() )
ras.move_to_d( x0, y0 );
else
ras.line_to_d( x0, y0 );
}
}
ras.render(ren, fgColor);
ras.reset();
}
void rasterizeCoverage(const Geometry* geometry, float value, RenderFrame& frame,
agg::rasterizer& ras, agg::rendering_buffer& buffer)
{
ConstGeometryIterator gi( geometry );
while( gi.hasMore() )
{
const Geometry* g = gi.next();
for( Geometry::const_iterator p = g->begin(); p != g->end(); p++ )
{
const osg::Vec3d& p0 = *p;
double x0 = frame.xf*(p0.x()-frame.xmin);
double y0 = frame.yf*(p0.y()-frame.ymin);
if ( p == g->begin() )
ras.move_to_d( x0, y0 );
else
ras.line_to_d( x0, y0 );
}
}
agg::renderer<span_coverage32, float32> ren(buffer);
ras.render(ren, value);
ras.reset();
}
// rasterizes a geometry to color
void rasterize(const Geometry* geometry, const osg::Vec4& color, RenderFrame& frame,
agg::rasterizer& ras, agg::rendering_buffer& buffer)
{
unsigned a = (unsigned)(127.0f+(color.a()*255.0f)/2.0f); // scale alpha up
agg::rgba8 fgColor = agg::rgba8( (unsigned)(color.r()*255.0f), (unsigned)(color.g()*255.0f), (unsigned)(color.b()*255.0f), a );
ConstGeometryIterator gi( geometry );
while( gi.hasMore() )
{
const Geometry* g = gi.next();
for( Geometry::const_iterator p = g->begin(); p != g->end(); p++ )
{
const osg::Vec3d& p0 = *p;
double x0 = frame.xf*(p0.x()-frame.xmin);
double y0 = frame.yf*(p0.y()-frame.ymin);
if ( p == g->begin() )
ras.move_to_d( x0, y0 );
else
ras.line_to_d( x0, y0 );
}
}
agg::renderer<agg::span_abgr32, agg::rgba8> ren(buffer);
ras.render(ren, fgColor);
ras.reset();
}
void draw_line(agg::rasterizer& ras,
double x1, double y1,
double x2, double y2,
double width)
{
double dx = x2 - x1;
double dy = y2 - y1;
double d = sqrt(dx*dx + dy*dy);
dx = width * (y2 - y1) / d;
dy = width * (x2 - x1) / d;
ras.move_to_d(x1 - dx, y1 + dy);
ras.line_to_d(x2 - dx, y2 + dy);
ras.line_to_d(x2 + dx, y2 - dy);
ras.line_to_d(x1 + dx, y1 - dy);
}
void draw_ellipse(agg::rasterizer& ras,
double x, double y,
double rx, double ry)
{
int i;
ras.move_to_d(x + rx, y);
// Here we have a fixed number of approximation steps, namely 360
// while in reality it's supposed to be smarter.
for(i = 1; i < 360; i++) {
double a = double(i) * 3.1415926 / 180.0;
ras.line_to_d(x + cos(a) * rx, y + sin(a) * ry);
}
}