How to design a font in a way that there will be no margin from its sides.
basically when I draw the letter "H" in the top=0, left=0 position, The top-left of this letter must be on the top left of the canvas.
What I have now with my font is this.
The tool I use now is FontForge.
Maybe something related to these options ?
Fonts have a UPM (Units Per Em) value that define their coordinates. The value is usually 1,000 for PostScript fonts and either 1,024 or 2,048 for TruType fonts but it doesn't have to be.
In your 'font info' dialog your accent heights are set to 969 so at a guess the font UPM is probably 1,000. Try changing your accent and cap height to 1,000 and possibly change your line gap to 0.
Another thing to think about is side bearings. Glyphs normally have left and right side bearings. Set your left side bearings to 0 and make sure you compensate for that on the right.
Also make sure each glyph starts at the very left and reaches the top of your font size (i.e. 1,000 or whatever your UPM is).
when I draw the letter "H" in the top=0, left=0 position, The top-left of this letter must be on the top left of the canvas.
Where and how are you drawing your text?
Any application or environment can be using any text rendering engine with any coordinate system that it wants. If you have a specific use-case where you need to draw the text as you said then you should be looking for a solution in that environment that would work for any font, not creating a new font with distorted metrics.
Your letterform is aliased. It has become that way due to the way your letterform is displayed at the size you chose. The appearance is an artifact of the rasterization of the image.
Supplying bitmaps for each font without hinting is a way to reduce the effect but will severely limit your display options to pixellated and jagged-looking letterforms wherever non-horizontal or non-vertical lines are shown.
Your "uglyfont" looks okay, otherwise.
"Uglyfont" will start to reveal its true beauty when larger display sizes are rendered or higher resolution for smaller fonts. : )
I don't use that software, but I see that your ascent height(s) are 969. Your ruler shows the top of your "H" at about 820. The discrepancy (about 140 units) is pretty close to the top margin in your screen capture.
So you need to lower the ascent or enlarge the H so that the top of the letterform is at 969.
Some of the margin may be the rendering engine being used also.
