CompositeTags and simple transparency problem

Hello

I have a very simple problem : I want to apply an uniform alpha value to a bitmap that is NOT transparent ( A=255 for all pixels)

Is it not possible ? or am I doing it wrong ?
[I am using VertexArray because the "sprite" may be flipped]

Thanks

Alain Thellier


if(DoBlend)
{

SrcA=((float)G->Blend.B.RGBA[3])/255.0;
SrcAfix=(SrcA*65536.0);
DstA=1.0-SrcA;
DstAfix=(DstA*65536.0);

CompMode=COMPOSITE_Src_Over_Dest;
flags= COMPFLAG_SrcFilter|COMPFLAG_IgnoreDestAlpha;

error = CompositeTags(CompMode,
srcbm,dstbm,
COMPTAG_VertexArray, P,
COMPTAG_VertexFormat,COMPVF_STW0_Present,
COMPTAG_NumTriangles,2,
COMPTAG_DestX,sx,
COMPTAG_DestY,sy,
COMPTAG_SrcAlpha ,SrcAfix,
COMPTAG_DestAlpha ,DstAfix,
COMPTAG_DestWidth ,slarge,
COMPTAG_DestHeight,shigh,
COMPTAG_Flags, flags ,
TAG_DONE);

}

@thellier

COMPFLAG_SrcAlphaOverride will do what you want.

Hans

Hello

Thanks for your help Hans

But it dont seems to works also with this fix...
Are you sure COMPTAG_VertexArray COMPTAG_SrcAlpha COMPFLAG_SrcAlphaOverride can works together ?

I mean perhaps COMPTAG_SrcAlpha COMPFLAG_SrcAlphaOverride only works with rectangular blit ? no ?


Alain