[ft-devel] supporting coloured bitmaps in FreeType
Hi to all FreeTypers after a long silence on my part - too much to do in CartoType. I have a simple proposal that would enable FreeType to support fonts which can create coloured glyphs. It is primarily intended for bitmap font formats used for emojis, emoticons and the like. I have an immediate need for this for a client, and will have to use it whether or not it becomes part of official FreeType, but it seems like a simple and non-disruptive change that would add a small amount of value. The idea is to add just two modes (for the moment - no need to be over-elaborate) to FT_Pixel_Mode, for premultiplied ARGB, and the same format using 8-bit indexes into a palette. These modes are convenient when creating bitmap fonts from PNG images. Thus FT_Pixel_Mode and its associated documentation comment become: /*/ /* */ /* Enum*/ /* FT_Pixel_Mode */ /* */ /* Description */ /*An enumeration type used to describe the format of pixels in a */ /*given bitmap. Note that additional formats may be added in the*/ /* future.*/ /* */ /* Values */ /*FT_PIXEL_MODE_NONE :: */ /* Value~0 is reserved. */ /* */ /*FT_PIXEL_MODE_MONO :: */ /* A monochrome bitmap, using 1~bit per pixel. Note that pixels*/ /* are stored in most-significant order (MSB), which means that */ /* the left-most pixel in a byte has value 128. */ /* */ /*FT_PIXEL_MODE_GRAY :: */ /* An 8-bit bitmap, generally used to represent anti-aliased glyph */ /* images. Each pixel is stored in one byte. Note that the number */ /* of `gray' levels is stored in the `num_grays' field of the */ /* @FT_Bitmap structure (it generally is 256). */ /* */ /*FT_PIXEL_MODE_GRAY2 :: */ /* A 2-bit per pixel bitmap, used to represent embedded */ /* anti-aliased bitmaps in font files according to the OpenType */ /* specification. We haven't found a single font using this*/ /* format, however. */ /* */ /*FT_PIXEL_MODE_GRAY4 :: */ /* A 4-bit per pixel bitmap, representing embedded anti-aliased */ /* bitmaps in font files according to the OpenType specification. */ /* We haven't found a single font using this format, however. */ /* */ /*FT_PIXEL_MODE_LCD :: */ /* An 8-bit bitmap, representing RGB or BGR decimated glyph images */ /* used for display on LCD displays; the bitmap is three times */ /* wider than the original glyph image. See also */ /* @FT_RENDER_MODE_LCD. */ /* */ /*FT_PIXEL_MODE_LCD_V :: */ /* An 8-bit bitmap, representing RGB or BGR decimated glyph images */ /* used for display on rotated LCD displays; the bitmap is three*/ /* times taller than the original glyph image. See also*/ /* @FT_RENDER_MODE_LCD_V. */ /* */ * /*FT_PIXEL_MODE_ARGB_PRE :: */ /* A 32-bit bitmap containing premultiplied ARGB pixels.*/ /* */ /*FT_PIXEL_MODE_ARGB_PRE_PALETTE :: */ /* An 8-bit bitmap containing palette indexes. Each value
Re: [ft-devel] supporting coloured bitmaps in FreeType
The idea is to add just two modes (for the moment - no need to be over-elaborate) to FT_Pixel_Mode, for premultiplied ARGB, and the same format using 8-bit indexes into a palette. These modes are convenient when creating bitmap fonts from PNG images. [...] This sounds great! Are you going to implement this? Werner ___ Freetype-devel mailing list Freetype-devel@nongnu.org https://lists.nongnu.org/mailman/listinfo/freetype-devel
Re: [ft-devel] supporting coloured bitmaps in FreeType
On 08/15/2012 11:10 AM, Werner LEMBERG wrote: The idea is to add just two modes (for the moment - no need to be over-elaborate) to FT_Pixel_Mode, for premultiplied ARGB, and the same format using 8-bit indexes into a palette. These modes are convenient when creating bitmap fonts from PNG images. [...] This sounds great! Are you going to implement this? Is there any common font format for these? b Werner ___ Freetype-devel mailing list Freetype-devel@nongnu.org https://lists.nongnu.org/mailman/listinfo/freetype-devel
Re: [ft-devel] supporting coloured bitmaps in FreeType
Well, what I'm suggesting is just adding these constants, which is a 5 minute patch. I'm not allowed to release my client's bitmap font format (which I invented) into the wild. It would be nice to have a standard coloured-bitmap font format but it would probably not be a good idea for me to invent it for obvious reasons. On 15/08/2012 16:10, Werner LEMBERG wrote: The idea is to add just two modes (for the moment - no need to be over-elaborate) to FT_Pixel_Mode, for premultiplied ARGB, and the same format using 8-bit indexes into a palette. These modes are convenient when creating bitmap fonts from PNG images. [...] This sounds great! Are you going to implement this? Werner ___ Freetype-devel mailing list Freetype-devel@nongnu.org https://lists.nongnu.org/mailman/listinfo/freetype-devel
Re: [ft-devel] supporting coloured bitmaps in FreeType
I have asked my client whether they will consider allowing me to make their bitmap font format public-domain so that someone can write a clean FreeType driver for it. I have a driver for it but it's not 'clean': it depends on a huge amount of other proprietary stuff. We would also need a clean implementation of the tool to create the font from PNG images. It's unlikely that they will say yes, but if you don't ask, you don't get. Graham On 15/08/2012 16:10, Werner LEMBERG wrote: The idea is to add just two modes (for the moment - no need to be over-elaborate) to FT_Pixel_Mode, for premultiplied ARGB, and the same format using 8-bit indexes into a palette. These modes are convenient when creating bitmap fonts from PNG images. [...] This sounds great! Are you going to implement this? Werner ___ Freetype-devel mailing list Freetype-devel@nongnu.org https://lists.nongnu.org/mailman/listinfo/freetype-devel ___ Freetype-devel mailing list Freetype-devel@nongnu.org https://lists.nongnu.org/mailman/listinfo/freetype-devel
