• Just looking around
    Futaura
    Posts: 8 from 2006/9/21
    From: UK
    I'm currently working on enabling full alpha channel support in IBrowse 2.5 for when it is running on MorphOS (well, using CGX V51 as a test to enable it), without a working MorphOS system, and am wondering if anybody can give clarification on the following as I seem to recall there were some discrepancies in CyberGraphX when it came to 24 vs 32-bit depths?

    1. For 24-bit bitmaps with an alpha channel, what do BMA_DEPTH and CYBRMATTR_DEPTH return - 24 or 32? Presumably, CYBRMATTR_BPPIX returns 4 (or 3 if there is no alpha). I need a way to detect if a bitmap allocated using a friend bitmap is alpha capable.

    2. When using AllocBitMap() to allocated a 24-bit bitmap with alpha, presumably I just need to specify the depth as 32?

    3. For 32-bit datatype images, I will be using PDTM_READPIXELARRAY with PBPAFMT_RGBA and writing it into a bitmap with WritePixelArray() RECTFMT_RGBA. Or do I need to use WritePixelArrayAlpha()?

    4. When rendering a bitmap with alpha, can I still use BltBitMap[RastPort]() or do I need to use the new BltBitMap*Alpha() equivalent functions in CGX?

    I couldn't find any documentation that answered these queries, so hoping somebody more knowledgable can help me :-)

    [ Edited by Futaura 18.09.2019 - 10:36 ]
  • »18.09.19 - 10:36
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