a test for output text by pycairo

cairo-text-example.py

#!/usr/bin/env python3
#under MIT license
#by yoxem 2017-04-02
import cairo

#設定寬高
#setting the width and height in inches.
#width of a4 = 8.3 inch = 8.3*72px
#height of a4 = 8.3 inch = 8.3*72px
WIDTH, HEIGHT = (8.3 * 72), (11.7 * 72)

#設定畫布
surface = cairo.PDFSurface("example.pdf", #匯出檔名
                           WIDTH, #寬度
                           HEIGHT) #高度

context = cairo.Context(surface)

context.scale(WIDTH, HEIGHT) #正規化帆布

#設定漸層(x0,y0,x1,y1)
#x,y從左上起算，以帆布比例為基準。x1 = 0.5 ，帆布一半寬
pat = cairo.LinearGradient (0.0, 0.0, 0.5,0.5)

#(offset, r, g, b, a)
#offset = 0 => x0,x0
pat.add_color_stop_rgba (0, 78/256, 226/256, 55/256, 0.4) 

#offset = 1 => x1,y1
pat.add_color_stop_rgba(1, 0, 0.7, 0, 1.0)





# Rectangle(x0, y0, x1, y1)
#x,y從左上起算，以帆布比例為基準。x1 = 0.5 ，帆布一半寬
context.rectangle (0, 0, 0.5, 0.5) 
context.set_source(pat) #設定式樣
context.fill() #填色


#移動座標(x,y)
context.move_to (0.1, 0.1)

'''輸入文字'''

#定義字形(字族,字斜,字重)
#設定文字(Font)
context.select_font_face("Freeserif",
cairo.FONT_SLANT_ITALIC, cairo.FONT_WEIGHT_BOLD)
#設置文字顏色(rgb)
context.set_source_rgb(0.2, 0.2, 0.2)
#設置文字大小
context.set_font_size(12/HEIGHT)
text = "hello world"
x_bearing, y_bearing, t_width, t_height = context.text_extents(text)[:4]
context.move_to(0.5 - t_width / 2 - x_bearing, 0.5 - t_height / 2 - y_bearing)
context.show_text(text)

context.select_font_face("Noto Sans CJK TC",
cairo.FONT_SLANT_NORMAL, cairo.FONT_WEIGHT_BOLD)
context.set_font_size(30/HEIGHT)
text="汝好 Lí hó!"
x_bearing, y_bearing, t_width, t_height = context.text_extents(text)[:4]
context.move_to(0.08, 0.1 - t_height / 2 - y_bearing)
context.show_text(text)


context.select_font_face("AR PL UMing TW",
                         cairo.FONT_SLANT_NORMAL, cairo.FONT_WEIGHT_NORMAL)
context.set_font_size(12/HEIGHT)
text='''臣亮言：先帝創業未半，而中道崩殂。'''
x_bearing, y_bearing, t_width, t_height = context.text_extents(text)[:4]
context.move_to(0.08, 0.15 - t_height / 2 - y_bearing)
context.show_text(text)

context.select_font_face("Freeserif",
                         cairo.FONT_SLANT_NORMAL, cairo.FONT_WEIGHT_NORMAL)

text='''Sîn Liōng giân: Sian-tē chhòng-gia̍p bī-poàⁿ, jî tiong-tō peng-cho͘. Ipsum lorem too long words that is very long to say it'''

context.move_to(0.08 + t_width + x_bearing+ \
                0.25 * context.text_extents(" ")[2] # 1/4 空白寬
                , 0.15 - t_height / 2 - y_bearing)
context.show_text(text)