java - Why does rendering to a FBO cause the texture to be darker? -

rendering fbo screen buffer appears make texture darker. seen here -> http://imgur.com/qznyy8u

rendertarget target = new rendertarget(display.getwidth(), display.getheight()); 

rendertarget class can found here : http://pastebin.com/anpbpsgv

gl11.glclear(gl11.gl_color_buffer_bit | gl11.gl_depth_buffer_bit);    // set color of quad (r,g,b,a) gl11.glcolor4f(5/255f, 35/255f,70/255f, 1f);  //bind render target target.bind();  // draw quad on fbo gl11.glbegin(gl11.gl_quads);     gl11.glvertex2f(0,0);     gl11.glvertex2f(0+200,0);     gl11.glvertex2f(0+200,0+200);     gl11.glvertex2f(0,0+200); gl11.glend();  target.unbind();  glenable(gl_texture_2d); // enable texturing glbindframebufferext(gl_framebuffer_ext, 0);// switch rendering on framebuffer glclearcolor (0.0f, 0.0f, 0.0f, 1.0f); glclear (gl_color_buffer_bit | gl_depth_buffer_bit);// clear screen , depth buffer on framebuffer black glbindtexture(gl_texture_2d, target.colortextureid);    // bind our fbo texture  //draw fbo on screen buffer glbegin(gl_quads);    gltexcoord2f(0.0f, 0.0f); glvertex2i(0,   0);      gltexcoord2f(1.0f, 0.0f); glvertex2i(display.getwidth(),  0);     gltexcoord2f(1.0f, 1.0f); glvertex2i(display.getwidth(), display.getheight());     gltexcoord2f(0.0f, 1.0f); glvertex2i(0, display.getheight()); glend();  gldisable(gl_texture_2d);  //draw same colour image without gonig through fbo gl11.glbegin(gl11.gl_quads);     gl11.glvertex2f(200,0);     gl11.glvertex2f(200+200,0);     gl11.glvertex2f(200+200,0+200);     gl11.glvertex2f(200,0+200); gl11.glend();  glflush (); 

classes used can found here pastebin.com/yrchp5vb , here pastebin.com/anpbpsgv

rendering texture not darker. draw texture darker:

gl11.glcolor4f(5/255f, 35/255f,70/255f, 1f); 

you never reset white, color stays is. default, gl uses gl_modulate texture environment mode, texture color gets multiplied color have set. see this question details.