font on image - bug?

[ecostanza]

Hello.

It seems to me that fonts are not correctly handled on images (e.g. for double buffering). In particular, if I try to render text on an image using a larger font than default, the text gets rendered very very small. This looks similar to a bug that was affecting font on canvas in an older release, about one year ago..

To demonstrate the problem I added an extra function "font_canvas_double_buffer" to the test_font.py script that is in the \src\ext\graphics folder of the source distribution. The full source is at the bottom of this message.

I am using version 1.4.3 (but the test_font.py is from the 1.4.2 source release) and testing on an E51.

Is this a bug, or am I doing something stupid in the way I handle the double buffering?

Thanks,
Enrico

from appuifw import *
from graphics import *
import e32
import time

app.body=c=Canvas()

fonts=[None,
       (None,20),
       'normal',
       ('normal',20),
       (u'fasfsafs',20),
       (u'Nokia Sans S60',10,0),
       (u'Nokia Sans S60',20),
       'dense',
       'title',
       (None,10,FONT_BOLD),
       (None,10,FONT_ITALIC),
       (None,10,FONT_ANTIALIAS),
       (None,10,FONT_NO_ANTIALIAS),
       ('normal',None,FONT_BOLD),
       ('normal',None,FONT_ITALIC),
       ('normal',None,FONT_NO_ANTIALIAS)      
       ]

def font_canvas():
    app.body=c=Canvas()
    c.clear()
    tl=(0,0)
    for font in fonts:
        text_to_draw=u'font:'+str(font)
        (bbox,advance,ichars)=c.measure_text(text_to_draw, font=font)
        print bbox, advance, ichars    
        # position the next piece of text so the top-left corner of its bounding box is at tl.    
        o=(tl[0]-bbox[0],tl[1]-bbox[1])
        # Draw the bounding box of the text as returned by measure_text
        c.rectangle((o[0]+bbox[0],o[1]+bbox[1],o[0]+bbox[2],o[1]+bbox[3]),outline=0x00ff00) 
        c.text(o, text_to_draw, font=font)                
        # Compute the new top-left.
        tl=(0,o[1]+bbox[3])

def font_canvas_double_buffer():
    #app.body=c=Canvas()
    canvas=Canvas()
    c = Image.new(canvas.size)
    c.clear()
    tl=(0,0)
    for font in fonts:
        text_to_draw=u'font:'+str(font)
        (bbox,advance,ichars)=c.measure_text(text_to_draw, font=font)
        print bbox, advance, ichars    
        # position the next piece of text so the top-left corner of its bounding box is at tl.    
        o=(tl[0]-bbox[0],tl[1]-bbox[1])
        # Draw the bounding box of the text as returned by measure_text
        c.rectangle((o[0]+bbox[0],o[1]+bbox[1],o[0]+bbox[2],o[1]+bbox[3]),outline=0x00ff00) 
        c.text(o, text_to_draw, font=font)                
        # Compute the new top-left.
        tl=(0,o[1]+bbox[3])
	
    app.body=canvas
    app.body.blit(c)

def measure_text():
    app.body=c=Canvas()
    c.clear()
    tl=(0,0)
    font='normal'
    for maxwidth in (50,100,150,200,250):
        text_to_draw=u'Lorem ipsum dolor sit amet'
        (bbox,advance,maxchars)=c.measure_text(text_to_draw, font=font, maxwidth=maxwidth)
        print bbox, advance, maxchars
        # Position the next piece of text so the top-left corner of its bounding box is at tl.    
        o=(tl[0]-bbox[0],tl[1]-bbox[1])
        # Draw the bounding box of the text as returned by measure_text
        c.rectangle((o[0]+bbox[0],o[1]+bbox[1],o[0]+bbox[2],o[1]+bbox[3]),outline=0x00ff00) 
        # Draw the maximum width specification line.
        c.line((tl[0],tl[1]+10,tl[0]+maxwidth,tl[1]+10), outline=0xff0000)
        # Draw the full text
        c.text(o, text_to_draw, font=font, fill=0x000080)                
        # Draw the text limited to given number of chars.
        c.text(o, text_to_draw[0:maxchars], font=font, fill=0)                
        # Compute the new top-left.
        tl=(0,o[1]+bbox[3]+3)

def font_benchmark():
    app.body=c=Canvas()
    c.clear()
    tl=(0,0)
    font='normal'
    text=u'Lorem ipsum dolor sit amet'
    def bench(name, func):
        start=time.time()
        func()
        end=time.time()
        print "%s: %d s"%(name,end-start)
    def default_font_test(c,t):
        for k in range(1000):
            c.text((0,30),t)        
    bench("default font", lambda:default_font_test(c,text))    

def font_attributes():
    app.body=c=Canvas()
    c.clear()
    y=20
    for font in [(None,None,0),
                 (None,None,FONT_ITALIC),
                 (None,None,FONT_BOLD),
                 (None,None,FONT_ITALIC|FONT_BOLD),
                 (None,None,FONT_ANTIALIAS),
                 (None,None,FONT_SUPERSCRIPT),
                 (None,None,FONT_SUBSCRIPT),
                 (None,None,FONT_NO_ANTIALIAS)]:
        c.text((20,y), u'abcd '+str(font), font=font)
        y+=20


def font_text():
    app.body=t=Text()
    for font in fonts:
        t.font=None
        t.add(u'font:'+str(font))
        t.font=font
        t.add(u'abcd1234')
        
        

lock=e32.Ao_lock()
app.screen='full'
app.exit_key_handler=lock.signal

app.menu=[(u'Fonts on canvas', font_canvas),
          (u'Fonts on canvas DBL Buff', font_canvas_double_buffer),
          (u'Measure text', measure_text),
          (u'Font attributes', font_attributes),
          (u'Font benchmark', font_benchmark),
          (u'Fonts on Text', font_text)]
font_canvas()
lock.wait()

[jplauril]

Yes, it's a bug - one that has recently been fixed in internal code.

http://sourceforge.net/tracker/index...55&atid=790646

The fix will be in the next release.

[ecostanza]

Thanks!

Any idea when the next release is expected?
Would you suggest that I get the sources from svn and complile it myself or shall I just wait?

Best,
Enrico

[ecostanza]

Actually I just looked at the sourceforge svn and the repository seems to be not at all updated.. where is the source?

Thanks,
Enrico

[jplauril]

Unfortunately we can't keep our internal version control system open to the public. You'll just have to wait for the next release.