klayout 源码分析系列续 渲染原理

klayout 源码分析系列续 渲染原理

1.先把图元画在bitmap上。

void
draw_ellipse (const db::DPoint &q1,const db::DPoint &q2,double length_u,bool sel,lay::CanvasPlane *bitmap,lay::Renderer &renderer)
{double sel_width = 2 / solution ();if (length_u < 1e-5 /*micron*/) {if (sel) {db::DBox b (q1 - db::DVector (sel_width * 0.5, sel_width * 0.5),q2 + db::DVector (sel_width * 0.5, sel_width * 0.5));renderer.draw (b, bitmap, bitmap, 0, 0);   //画图元} else {renderer.draw (db::DEdge (q1, q1), 0, bitmap, 0, 0);}...
}

2.画布Canvas是一个widget,画布刷新时，会绘制bitmap。

//layLayoutCanvas
void
LayoutCanvas::paintEvent (QPaintEvent *)
{...do_render (m_viewport_l, *this, false);...
}//layViewObject
void 
ViewObjectWidget::do_render (const lay::Viewport &vp, lay::ViewObjectCanvas &canvas, bool st)
{if (st) {m_needs_update_static = false;}for (object_iterator obj = begin_objects (); obj != end_objects (); ++obj) {if (obj->m_static == st && obj->is_visible () && (! m_view_objects_dismissed || ! obj->get_dismissable ())) {BEGIN_PROTECTED_SILENTobj->render (vp, canvas);   //画图元END_PROTECTED_SILENT}}canvas.sort_planes ();
}