Source code for qt_renderer

from numpy import degrees
from pose import Pose
from renderer import Renderer
from PyQt4.QtGui import QPainter,QColor,QPolygonF,QPen
from PyQt4.QtCore import QPointF,QLineF,QRectF,Qt

[docs]class QtRenderer(Renderer): """An implementation of :class:`~renderer.Renderer` for PyQt4. This renderer will draw on any `QPaintDevice` """ def __init__(self, paint_device): """Creates a new renderer based on a QPaintDevice pd""" self._grid_pen = QPen(QColor(0x808080)) self._grid_pen.setStyle(Qt.DashLine) self._painter = None Renderer.__init__(self, paint_device) def set_canvas(self, canvas): """Tell the renderer to draw on canvas The type of canvas is implementation-dependent""" if self._painter is not None: self._painter.restore() self._painter.restore() self._painter.end() self._paintdevice = canvas self._painter = QPainter(canvas) self._painter.setRenderHint(QPainter.Antialiasing) # invert the y axis self._painter.scale(1,-1) self._painter.translate(0,-canvas.height()) Renderer.set_canvas(self,canvas) def _get_canvas_size(self,pd): """Get the canvas size tuple (width,height)""" return (pd.width(), pd.height()) def push_state(self): """Store the current state on the stack. Current state includes default pose, pen and brush""" ### FIXME store things def pop_state(self): """Restore the last saved state from the stack The state includes default pose, pen and brush""" ### FIXME store things self._painter.restore() def _calculate_bounds(self): transform = self._painter.worldTransform().inverted()[0] xs,ys = zip(,0.0),,float(self.size[1])),[0]),float(self.size[1])),[0]),0.0) ) self._bounds = (min(xs), min(ys), max(xs), max(ys)) def _draw_grid(self): self.reset_pose() self._painter.setPen(self._grid_pen) xmin, ymin, xmax, ymax = self._bounds # Determine min/max x & y line indices: x_ticks = (int(xmin//self._grid_spacing), int(xmax//self._grid_spacing + 1)) y_ticks = (int(ymin//self._grid_spacing), int(ymax//self._grid_spacing + 1)) self._painter.drawLines( [QLineF(xmin, i * self._grid_spacing, xmax, i * self._grid_spacing) for i in range(*y_ticks)]) self._painter.drawLines( [QLineF(i * self._grid_spacing, ymin, i * self._grid_spacing, ymax) for i in range(*x_ticks)]) def scale(self, factor): """Scale drawing operations by factor To be implemented in subclasses.""" self._painter.scale(factor,factor) def rotate(self, angle): """Rotate canvas by angle (in radians) To be implemented in subclasses.""" self._painter.rotate(degrees(angle)) def translate(self, dx, dy): """Translate canvas by dx, dy To be implemented in subclasses.""" self._painter.translate(dx,dy) def clear_screen(self): """Erases the current screen with a white brush""" self._painter.resetTransform() self.set_pen(0xFFFFFF) self.set_brush(0xFFFFFF) self.draw_rectangle(0,0,self.size[0],self.size[1]) self._painter.restore() Renderer.clear_screen(self) @staticmethod def __qcolor(color): """Returns qcolor for a given ARGB color""" c = QColor(color) if color > 0xFFFFFF: c.setAlpha((color >> 24) & 0xFF) return c def set_pen(self,color=0, thickness=0): """Sets the line color and thickness. Color is interpreted as 0xAARRGGBB.""" if color is None: self._painter.setPen(Qt.NoPen) else: self._painter.setPen(QPen(self.__qcolor(color),thickness)) def set_brush(self,color): """Sets the fill color. Color is interpreted as 0xAARRGGBB.""" if color is None: self._painter.setBrush(Qt.NoBrush) else: self._painter.setBrush(self.__qcolor(color)) def draw_polygon(self,points): """Draws a polygon. Expects a list of points as a list of tuples or as a numpy array.""" self._painter.drawPolygon(QPolygonF([QPointF(*point[:2]) for point in points])) def draw_ellipse(self, cx, cy, ra, rb = None): """Draws an ellipse.""" if rb is None: rb = ra self._painter.drawEllipse(QRectF(cx-ra,cy-ra,2*ra,2*rb)) def draw_rectangle(self, x, y, w, h): """Draws a rectangle.""" self._painter.drawRect(QRectF(x,y,w,h)) def draw_text(self, text, x, y, bgcolor = 0): """Draws a text string at the defined position.""" pass def draw_line(self, x1, y1, x2, y2): """Draws a line using the current pen from (x1,y1) to (x2,y2)""" self._painter.drawLine(QLineF(x1,y1,x2,y2))