I set world.setAmbientLight(255, 255, 255) ... tm.replaceTexture(...) works correctly... ok, I fond where is problem...
this code return every what in set in fb.clear(), after this clear command can be whatever... so if I use fb.clear(RGBColor.RED) texture will be red,...
tex = new Texture(64, 64);
fb.setRenderTarget(tex);
fb.clear();
fb.blit(tm.getTexture("texture2"), 0, 0, 0, 0, 64, 64, false);
fb.display();
fb.removeRenderTarget();
tm.replaceTexture("texture", tex);
but this works fine... fb.clear() is not used
tex = new Texture(64, 64);
fb.setRenderTarget(tex);
fb.blit(tm.getTexture("texture2"), 0, 0, 0, 0, 64, 64, false);
fb.display();
fb.removeRenderTarget();
tm.replaceTexture("texture", tex);