Texture unit for general purpose computing

An apparatus comprising:

• a processing entity;
• a memory coupled to said processing entity;
• and
• a programmable linear interpolator coupled to said processing entity to calculate a dot product to determine that a dot product coefficient is negative and change the sign of the coefficient and compensate for the sign change by passing a control mask for each of the texels with a negative coefficient to a texture control and to determine that a mask having one value means that the corresponding coefficient is positive and the mask having another value means that the corresponding coefficient is negative.

A non-transitory computer readable medium storing instructions to enable a computer to:

• determine that a dot product coefficient determined by a texture unit is negative;
• change the sign of the coefficient to a positive value;
• and
• compensate for the sign change by passing a control mask for each of the texels with a negative coefficient to a texture control and to determine that a mask having one value means that the corresponding coefficient is positive and the mask having another value means that the corresponding coefficient is negative.