+ /** Sets the gamma value used for mapping output colors. Allowed range is
+ from 0.1 to 10. */
+ void set_gamma(float);
+
+ /** Sets output mapping to sRGB. This is almost, but not exactly equivalent
+ to set_gamma(2.2). */
+ void set_srgb();
+
+ /// Sets output mapping to linear. This is equivalent to set_gamma(1).
+ void set_linear();
+