display_texture    50 apps/opengl_demo/layout.cpp     OpenGLHelpers::display_texture(texture_id, 2.0*x0/state.window_width-1.0, 2.0*x1/state.window_width-1.0, 2.0*y0/state.window_height-1.0, 2.0*y1/state.window_height-1.0);
display_texture    16 apps/opengl_demo/opengl_helpers.h     void display_texture(GLuint texture_id, float x0, float x1, float y0, float y1);