+ crop_at_page[page_num] = page_crop
+ return crop_at_page
+
+
+def build_single_pages_output(writer, pages_to_add, crop_at_page):
+ print("building 1-input-page-per-output-page book")
+ odd_page = True
+ for i, page in enumerate(pages_to_add):
+ page.add_transformation(pypdf.Transformation().translate(tx=-crop_at_page[i].left, ty=-crop_at_page[i].bottom))
+ page.add_transformation(pypdf.Transformation().scale(crop_at_page[i].zoom, crop_at_page[i].zoom))
+ page.mediabox.right = crop_at_page[i].remaining_width * crop_at_page[i].zoom
+ page.mediabox.top = crop_at_page[i].remaining_height * crop_at_page[i].zoom
+ writer.add_page(page)
+ odd_page = not odd_page
+ print(f"built page number {i+1} (of {len(pages_to_add)})")
+
+
+def build_nup4_output(writer, pages_to_add, crop_at_page, args_print_margin, args_analyze, canvas_class):
+ print("-n: building 4-input-pages-per-output-page book")
+ print(f"-m: applying printable-area margin of {args_print_margin}cm")
+ if args_analyze:
+ print("-a: drawing page borders, spine limits")
+ nup4_geometry = Nup4Geometry(args_print_margin)
+ pages_to_add, new_i_order = resort_pages_for_nup4(pages_to_add)
+ nup4_i = 0
+ page_count = 0
+ is_front_page = True
+ for i, page in enumerate(pages_to_add):
+ if nup4_i == 0:
+ new_page = pypdf.PageObject.create_blank_page(width=A4_WIDTH, height=A4_HEIGHT)
+ corrected_i = new_i_order[i]
+ nup4_inner_page_transform(page, crop_at_page[corrected_i], nup4_geometry, nup4_i)
+ nup4_outer_page_transform(page, nup4_geometry, nup4_i)
+ new_page.merge_page(page)
+ page_count += 1
+ print(f"merged page number {page_count} (of {len(pages_to_add)})")
+ nup4_i += 1
+ if nup4_i > 3:
+ ornate_nup4(writer, args_analyze, is_front_page, new_page, nup4_geometry, canvas_class)
+ writer.add_page(new_page)
+ nup4_i = 0
+ is_front_page = not is_front_page
+
+
+def resort_pages_for_nup4(pages_to_add):
+ new_page_order = []
+ new_i_order = []
+ eight_pack = []
+ i = 0
+ n_eights = 0
+ for page in pages_to_add:
+ if i == 0:
+ eight_pack = []
+ eight_pack += [page]
+ i += 1
+ if i == 8:
+ i = 0
+ for n in PAGE_ORDER_FOR_NUP4:
+ new_i_order += [8 * n_eights + n]
+ new_page_order += [eight_pack[n]]
+ n_eights += 1
+ return new_page_order, new_i_order
+
+
+def nup4_inner_page_transform(page, crop, nup4_geometry, nup4_i):
+ page.add_transformation(pypdf.Transformation().translate(ty=(A4_HEIGHT / crop.zoom - (A4_HEIGHT - crop.top))))
+ if nup4_i == 0 or nup4_i == 2:
+ page.add_transformation(pypdf.Transformation().translate(tx=-crop.left))
+ elif nup4_i == 1 or nup4_i == 3:
+ page.add_transformation(pypdf.Transformation().translate(tx=(A4_WIDTH / crop.zoom - (A4_WIDTH - crop.right))))
+ page.add_transformation(pypdf.Transformation().scale(crop.zoom * nup4_geometry.shrink_for_spine, crop.zoom * nup4_geometry.shrink_for_spine))
+ if nup4_i == 2 or nup4_i == 3:
+ page.add_transformation(pypdf.Transformation().translate(ty=-2*nup4_geometry.margin/nup4_geometry.shrink_for_margin))
+
+
+def nup4_outer_page_transform(page, nup4_geometry, nup4_i):
+ page.add_transformation(pypdf.Transformation().translate(ty=(1-nup4_geometry.shrink_for_spine)*A4_HEIGHT))
+ if nup4_i == 0 or nup4_i == 1:
+ y_section = A4_HEIGHT
+ page.mediabox.bottom = A4_HALF_HEIGHT
+ page.mediabox.top = A4_HEIGHT
+ if nup4_i == 2 or nup4_i == 3:
+ y_section = 0
+ page.mediabox.bottom = 0
+ page.mediabox.top = A4_HALF_HEIGHT
+ if nup4_i == 0 or nup4_i == 2:
+ x_section = 0
+ page.mediabox.left = 0
+ page.mediabox.right = A4_HALF_WIDTH
+ if nup4_i == 1 or nup4_i == 3:
+ page.add_transformation(pypdf.Transformation().translate(tx=(1-nup4_geometry.shrink_for_spine)*A4_WIDTH))
+ x_section = A4_WIDTH
+ page.mediabox.left = A4_HALF_WIDTH
+ page.mediabox.right = A4_WIDTH
+ page.add_transformation(pypdf.Transformation().translate(tx=x_section, ty=y_section))
+ page.add_transformation(pypdf.Transformation().scale(QUARTER_SCALE_FACTOR, QUARTER_SCALE_FACTOR))
+
+
+def ornate_nup4(writer, args_analyze, is_front_page, new_page, nup4_geometry, canvas_class):
+ if args_analyze:
+ # borders
+ packet = io.BytesIO()
+ c = canvas_class(packet, pagesize=A4)
+ c.setLineWidth(0.1)
+ c.line(0, A4_HEIGHT, A4_WIDTH, A4_HEIGHT)
+ c.line(0, A4_HALF_HEIGHT, A4_WIDTH, A4_HALF_HEIGHT)
+ c.line(0, 0, A4_WIDTH, 0)
+ c.line(0, A4_HEIGHT, 0, 0)
+ c.line(A4_HALF_WIDTH, A4_HEIGHT, A4_HALF_WIDTH, 0)
+ c.line(A4_WIDTH, A4_HEIGHT, A4_WIDTH, 0)
+ c.save()
+ new_pdf = pypdf.PdfReader(packet)
+ new_page.merge_page(new_pdf.pages[0])
+ printable_offset_x = nup4_geometry.margin
+ printable_offset_y = nup4_geometry.margin * A4_HEIGHT / A4_WIDTH
+ new_page.add_transformation(pypdf.Transformation().scale(nup4_geometry.shrink_for_margin, nup4_geometry.shrink_for_margin))
+ new_page.add_transformation(pypdf.Transformation().translate(tx=printable_offset_x, ty=printable_offset_y))
+ x_left_spine_limit = A4_HALF_WIDTH * nup4_geometry.shrink_for_spine
+ x_right_spine_limit = A4_WIDTH - x_left_spine_limit
+ if args_analyze or is_front_page:
+ packet = io.BytesIO()
+ c = canvas_class(packet, pagesize=A4)
+ if args_analyze:
+ # spine lines
+ c.setLineWidth(0.1)
+ c.line(x_left_spine_limit, A4_HEIGHT, x_left_spine_limit, 0)
+ c.line(x_right_spine_limit, A4_HEIGHT, x_right_spine_limit, 0)
+ if is_front_page:
+ c.setLineWidth(0.2)
+ draw_cut(c, x_left_spine_limit, (1))
+ draw_cut(c, x_right_spine_limit, (-1))
+ if args_analyze or is_front_page:
+ c.save()
+ new_pdf = pypdf.PdfReader(packet)
+ new_page.merge_page(new_pdf.pages[0])
+
+
+def draw_cut(canvas, x_spine_limit, direction):
+ outer_start_x = x_spine_limit - 0.5 * CUT_WIDTH * direction
+ inner_start_x = x_spine_limit + 0.5 * CUT_WIDTH * direction
+ middle_point_y = A4_HALF_HEIGHT + MIDDLE_POINT_DEPTH * direction
+ end_point_y = A4_HALF_HEIGHT + CUT_DEPTH * direction
+ canvas.line(inner_start_x, A4_HALF_HEIGHT, x_spine_limit, end_point_y)
+ canvas.line(x_spine_limit, end_point_y, x_spine_limit, middle_point_y)
+ canvas.line(x_spine_limit, middle_point_y, outer_start_x, A4_HALF_HEIGHT)