kc3-lang/SDL/include

Diff

  • Show log

    Commit

  • Hash : 981e0d36
    Author : Sam Lantinga
    Date : 2020-01-16T08:52:59 

    Fixed bug 4903 - Lack of color multiply with alpha (SDL_BLENDMODE_MOD + SDL_BLENDMODE_BLEND) blending mode for all renderers

Konrad

This kind of blending is rather quite useful and in my opinion should be available for all renderers. I do need it myself, but since I didn't want to use a custom blending mode which is supported only by certain renderers (e.g. not in software which is quite important for me) I did write implementation of SDL_BLENDMODE_MUL for all renderers altogether.

SDL_BLENDMODE_MUL implements following equation:

dstRGB = (srcRGB * dstRGB) + (dstRGB * (1-srcA))
dstA = (srcA * dstA) + (dstA * (1-srcA))

Background:

https://i.imgur.com/UsYhydP.png

Blended texture:

https://i.imgur.com/0juXQcV.png

Result for SDL_BLENDMODE_MOD:

https://i.imgur.com/wgNSgUl.png

Result for SDL_BLENDMODE_MUL:

https://i.imgur.com/Veokzim.png

I think I did cover all possibilities within included patch, but I didn't write any tests for SDL_BLENDMODE_MUL, so it would be lovely if someone could do it.

  • Properties

  • Git HTTP https://git.kmx.io/kc3-lang/SDL.git
    Git SSH git@git.kmx.io:kc3-lang/SDL.git
    Public access ? public
    Description

    Fork of https://github.com/libsdl-org/SDL
    Users
    		 thodg_m kc3_lang_org thodg_w www_kmx_io thodg thodg_l
    Tags

kmx.io     mail     discord kmxgit v0.4.0