<div class="gmail_quote">On 21 July 2011 11:27, Harshula <<a href="mailto:harshula@gmail.com">harshula@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"> Hi Shriramana, <div class="im"> On Thu, 2011-07-21 at 09:27 +0530, Shriramana Sharma wrote: > On 07/21/2011 09:04 AM, Pravin Satpute wrote: </div><div class="im">> > 1) In pango we have faced problem of backspace due to decomposition. > > i.e. U+0958 was getting decomposed into U+0915 and U+093C, so for > > entered character was required 2 backspaces to delete. > > That doesn't sound right. The backspace should erase the last character > that was input. Rendering engines should only take care of rendering > whatever sequence of characters has been input and not change the > sequence of characters right? </div>That's a bit simplistic. When a smart input method engine (IME) is activated, it can make sure that a backspace erases only the part of the glyph that the last keystroke inserted. e.g. It takes four keystrokes to generate කෝ (Sinhala syllable) with a particular IM. Another IM requires only two keystrokes. Each of these IMs controls how the backspace key operates and only deletes the part of the glyph inserted by the last keystroke. However, when the smart IME is deactivated, backspace then becomes someone else's responsibility. Here we see behaviour differences. e.g. For කෝ , Pango/gedit deletes in decomposed form (press backspace 4 times) and ICU/OpenOffice deletes in composed form (press backspace 2 times). Perhaps, there should be a separate discussion on which behaviour should be the default? Also, IIRC, Pango had a separate module that handled the cursor movement. I remember having to modify it for Sinhala. </blockquote><div> Looks like we are going off topic little bit so changed subject line, but i would like to ask one thing is there any standard define for Backspace and Delete keys behaviour? I think Unicode has given this but i have not find it yet anyone knows anything? Regards, Pravin S </div></div>