[whatwg] Canvas lack of drawString method (p.s.)

Stefan Haustein sh at kobjects.org
Tue Oct 17 15:19:09 PDT 2006

p.s.: To simplify coping with changing font sizes, it probably makes 
sense to add an "align" parameter (left|center|right 
top|center|baseline|bottom) to the drawString call...

Stefan Haustein wrote:
> Hi,
> I would like to second the drawString() request.
> It makes sense to have a simple API, but it should be balanced with 
> application simplicity and readability to some extent. Doing CSS black 
> magic to overlay text and a Canvas object just seems inadequate for 
> something like axis labeling.
> As noted earlier by somebody else (did not find the mail...), we would 
> also need a simple Font object, but the minimum requirements seem 
> rather simple:
> Font Canvas.createFont(String cssFontProperties);
> Canvas.setFont(Font font) // set current font
> Canvas.drawString(int x, int y, String text);
> Font Canvas.getFont() // current font
> int Font.stringWidth(String s);
> int Font.getHeight();  // includes leading
> int Font.getBaselinePosition();
> int Font.getAscent();
> int Font.getDescent();
> Best regards
> Stefan Haustein
> Alfonso Baqueiro wrote:
>> Hello Charles,
>> 2006/10/17, Charles Iliya Krempeaux <supercanadian at gmail.com 
>> <mailto:supercanadian at gmail.com>>:
>>     Hello Alfonso,
>>     On 10/17/06, *Alfonso Baqueiro* < abaqueiro at gmail.com
>>     <mailto:abaqueiro at gmail.com>> wrote:
>>         The canvas component is very promising, but the lack of
>>         drawString method could be a great error for its success, this
>>         lack is a huge limitation, how could you resolve this problem?
>>     I believe that some people's reason for not wanting to add it was
>>     because of Accessibility concerns.
>>     Although normal text in a webpage... or even a text image (with
>>     the "alt" attribute filled in properly) could be "read" by a
>>     person with disabilities, text embedded in the canvas element
>>     could not.
>>     Perhaps people need to think about how to add Accessibility to the
>>     canvas while allowing a "drawString" procedure.
>> Well a drawString method in canvas can be used for drawing the axis 
>> labels or values on a dinamic javascript graphic, but is non sense an 
>> aural reader read it, theres no way (yet) to read an image to a 
>> blinded people, there are cases where is imposible the accessibility, 
>> is imposible for a blind to play video games, and accessibility dont 
>> stop the video games creation. In the case of images or the canvas 
>> the alt attribute could do the job.
>>     See ya

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