"multiply" blending mode?

[suicvne]

is a "multiply" blending mode possible at all? i'd like to use it to implement some psuedo 2D lighting (which I've done before in XNA) but the best I could get was additive which didn't look as good.

[suicvne]

i experimented with the source code a bit trying the following blend func:

sceGuBlendFunc(GU_ADD, GU_FIX, GU_SRC_COLOR, 0, 0);

it works with a non-transparent image (ie: black background white radial gradient) but completely breaks with a transparent one (only renders the pixels in the corners as full black?)

essentially, what my custom "mult" mode looks like is this:

sceGuBlendFunc(GU_ADD, GU_FIX, GU_SRC_COLOR, 0, 0);
sceGuTexFunc(GU_TFX_MODULATE, GU_TCC_RGBA);
sceGuAmbientColor(coeff1);
osl_currentAlphaCoeff = coeff1;
osl_currentAlphaCoeff2 = coeff2;

i'm not quite familiar with sceGuTexFunc or sceGuAmbientColor so I just left those similar as the other cases.

the method i use is:

1. draw the base scene
2. set blend to mult
3. overlay a rectangle with the 'ambient light'
4. draw lightmaps

here is a non-transparent png being used as the base light

and here is a semi-transparent png being used as the base light.

both images are identical with the exception of one having a black background and the other having a transparent background.

something like this is essentially what i'm going for