pxt
#1
Hello!
im trying to render a video with transparent alpha, to incrust in other video, just like this:
its possible using FBO?
im doing something like this:
pseudocode
fbo.begin();
ofClearColor(0,0,0,0); // ?
shader.begin();
ofSphere();
shader.end();
fbo.end();
Hi,
you need to allocate the FBO so it has an alpha channel.
Use the following for an 8 bit “regular” fbo
fbo.allocate(width, height, GL_RGBA );
Use the following for an 32 bit floating point fbo
fbo.allocate(width, height, GL_RGBA32F_ARB);
Look at examples/gl/fboTrailsExample to see what’s the difference between these.
Hope this helps.
cheers
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