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# Major library imports
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# PDF imports from reportlab
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from reportlab.pdfgen.canvas import Canvas
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from reportlab.lib.pagesizes import letter, A4
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from reportlab.lib.pagesizes import letter, A4, landscape
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from reportlab.lib.units import inch, cm, mm, pica
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except ImportError:
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from kiva.pdf import GraphicsContext
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"landscape_letter": landscape(letter),
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"landscape_A4": landscape(A4)
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if Canvas is not None:
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class PdfPlotGraphicsContext(GraphicsContext):
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pagesize = "letter" # Enum("letter", "A4")
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# A tuple (x, y, width, height) specifying the box into which the plot
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# should be rendered. **x** and **y** correspond to the lower-left hand
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# coordinates of the box in the coordinates of the page (i.e. 0,0 is at the
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# lower left). **width** and **height** can be positive or negative;
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# should be rendered. **x** and **y** correspond to the lower-left
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# hand coordinates of the box in the coordinates of the page
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# (i.e. 0,0 is at the lower left). **width** and **height** can be
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# positive or negative;
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# if they are positive, they are interpreted as distances from (x,y);
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# if they are negative, they are interpreted as distances from the right
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# and top of the page, respectively.
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# if they are negative, they are interpreted as distances from the
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# right and top of the page, respectively.
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dest_box = (0.5, 0.5, -0.5, -0.5)
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# The units of the values in dest_box
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dest_box_units = "inch" # Enum("inch", "cm", "mm", "pica")
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def __init__(self, pdf_canvas=None, filename=None, pagesize=None,
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dest_box=None, dest_box_units=None):
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self.dest_box_units = dest_box_units
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if pdf_canvas == None:
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if pdf_canvas is None:
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pdf_canvas = self._create_new_canvas()
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GraphicsContext.__init__(self, pdf_canvas)
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""" Adds a new page to the PDF canvas and makes that the current
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warnings.warn("PDF Canvas has not been created yet.")
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# We'll need to call _initialize_page() before drawing
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self._page_initialized = False
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def render_component(self, component, container_coords=False,
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halign="center", valign="top"):
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""" Erases the current contents of the graphics context and renders the
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given component at the maximum possible scaling while preserving aspect
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""" Erases the current contents of the graphics context and renders
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the given component at the maximum possible scaling while
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preserving aspect ratio.
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container_coords : Boolean
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Whether to use coordinates of the component's container
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halign : "center", "left", "right"
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Determines the position of the component if it is narrower than the
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graphics context area (after scaling)
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Determines the position of the component if it is narrower than
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the graphics context area (after scaling)
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valign : "center", "top", "bottom"
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Determiens the position of the component if it is shorter than the
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graphics context area (after scaling)
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Determiens the position of the component if it is shorter than
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the graphics context area (after scaling)
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If *container_coords* is False, then the (0,0) coordinate of this
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graphics context corresponds to the lower-left corner of the
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component's **outer_bounds**. If *container_coords* is True, then the
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method draws the component as it appears inside its container, i.e., it
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treats (0,0) of the graphics context as the lower-left corner of the
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container's outer bounds.
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component's **outer_bounds**. If *container_coords* is True, then
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the method draws the component as it appears inside its container,
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i.e., it treats (0, 0) of the graphics context as the lower-left
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corner of the container's outer bounds.
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if not self._page_initialized:
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# Make sure the origin is set up as before.
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self._initialize_page(self.gc)
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x, y = component.outer_position
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if container_coords:
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width, height = component.container.bounds
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width, height = component.outer_bounds
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# Compute the correct scaling to fit the component into the available
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# canvas space while preserving aspect ratio.
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# Compute the correct scaling to fit the component into the
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# available canvas space while preserving aspect ratio.
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units = UNITS_MAP[self.dest_box_units]
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pagesize = PAGE_SIZE_MAP[self.pagesize]
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self.translate_ctm(trans_x, trans_y)
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self.scale_ctm(scale, scale)
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self.clip_to_rect(0, 0, width, height)
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self.clip_to_rect(-x, -y, width, height)
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old_bb_setting = component.use_backbuffer
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component.use_backbuffer = False
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component.draw(self, view_bounds=(0, 0, width, height))
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def _create_new_canvas(self):
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""" Create the PDF canvas context.
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x, y, w, h, = self._get_bounding_box()
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pagesize = PAGE_SIZE_MAP[self.pagesize]
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units = UNITS_MAP[self.dest_box_units]
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gc = Canvas(filename=self.filename, pagesize=pagesize)
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width = pagesize[0] * units * inch / 72.0
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height = pagesize[1] * units * inch / 72.0
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self._initialize_page(gc)
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def _get_bounding_box(self):
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""" Compute the bounding rect of a page.
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pagesize = PAGE_SIZE_MAP[self.pagesize]
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units = UNITS_MAP[self.dest_box_units]
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x = self.dest_box[0] * units
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y = self.dest_box[1] * units
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w = self.dest_box[2] * units
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h = self.dest_box[3] * units
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w += pagesize[0] * units * inch / PAGE_DPI
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h += pagesize[1] * units * inch / PAGE_DPI
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if w < 0 or h < 0:
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warnings.warn("Margins exceed page dimensions.")
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def _initialize_page(self, gc):
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""" Make sure the origin is set to something consistent.
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x, y, w, h, = self._get_bounding_box()
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path = gc.beginPath()
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path.rect(0, 0, w, h)
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gc.clipPath(path, stroke=0, fill=0)
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self._page_initialized = True
added
removed
chaco/pdf_graphics_context.py
