Chroma Key Operations with Multi Layering

Hi,

I am currently experimenting with the HW supported Layer capabilities of
Photon. (coral)
I already have some test programs using alpha blending that work quite
fine. Now I wanted to try out the chroma keying between layers, but I
can’t find a way to get this to work.

This is what I am doing to enable chroma keying:

_Pg_chroma chroma;
chroma.op = Pg_CHROMA_NODRAW |Pg_CHROMA_SRC_MATCH;
chroma.color = Pg_WHITE;
PgSetLayerArg( layer_idx, Pg_LAYER_ARG_CHROMA, &chroma, sizeof( chroma ) );

I am expecting now that white is transparent and shows the layer below,
but that doesn’t work.

Are there any examples that are not in the QNX documentation available?

— Wolfram

Wolfram Manthey <qnxnews@gmx.de> wrote in message
news:4055CE4C.4000303@gmx.de

Hi,

I am currently experimenting with the HW supported Layer capabilities of
Photon. (coral)
I already have some test programs using alpha blending that work quite
fine. Now I wanted to try out the chroma keying between layers, but I
can’t find a way to get this to work.

This is what I am doing to enable chroma keying:

_Pg_chroma chroma;
chroma.op = Pg_CHROMA_NODRAW |Pg_CHROMA_SRC_MATCH;
chroma.color = Pg_WHITE;
PgSetLayerArg( layer_idx, Pg_LAYER_ARG_CHROMA, &chroma, sizeof(
chroma ) );

I am expecting now that white is transparent and shows the layer below,
but that doesn’t work.

Try:
chroma.op = Pg_CHROMA_VALID | Pg_CHROMA_NODRAW | Pg_CHROMA_SRC_MATCH;


Are there any examples that are not in the QNX documentation available?

I’m not aware of any at this point, but someone else may be able to comment
better.

— Wolfram