//--------------------------------------------------------------
void ofApp::setup(){
fbo.allocate(400, 400, GL_RGBA, 4);
fbo.begin();
ofClear(ofColor(255,0,0,0));
fbo.end();
}
In my code, as you can see I clear fbo with zero alpha, so the color should be invisible anyway.
But if I draw a circle onto the fbo, I can see the color still exist around the circle.
//--------------------------------------------------------------
void ofApp::draw(){
fbo.begin();
ofSetColor(255, 255, 255);
ofSetCircleResolution(50);
ofDrawCircle(200, 200, 200);
fbo.end();
fbo.draw(0, 0);
}
As you can see there is thin red outline.
If I clear it with the same color as the background color, then it looks clean but otherwise I think it always gets affected by the initial cleared color.
If It’s inevitable, would there be any trick to make the Fbo’d shape look clean regardless of the background color?