GLSL/Error_Pixel

    //:ES2_AA2_MAC_DEB: My debug macro, true if positive.
    //:        pix_err: PIXel ERRor    ( Stores Hex Error Code )
    //:        pix_fra: PIXel FRAgment ( fragment color        )

    #if( ES2_AA2_MAC_DEB > 0 ) //:///////////////////////////://

        //:ASSIGN_TO_ZERO_AT_TOP_OF_FUNCTION!!!!!!!!!!!!!!!!!!!!
        uint pix_err =( 0x00000000 );

    #endif //:///////////////////////////////////////////////://


    //: ...Later when you want to error check....


    #if( ES2_AA2_MAC_DEB > 0 ) //:///////////////////////////://

        if( Ax1-Ax0+uint(1) != ES2_zoo_wid ||
            Ay1-Ay0+uint(1) != ES2_zoo_hig ){

            //: The first error encountered puts program     ://
            //: into invalid state, so we want to make sure  ://
            //: we never override the first error tripped.   ://
            //: So always guard with comparison to           ://
            //: 0x00000000 before setting to the error color.://
            if( uint(0x00000000) == pix_err ){
                pix_err=( uint(0xFF9000FF) );
            };;
        };;

    #endif //:///////////////////////////////////////////////://


    ... Do more code.......................................
    ... DONT TRY TO EXIT EARLY if error is tripped ........
    ... that will just turn your code into spaghetti ......


    #if( ES2_AA2_MAC_DEB > 0 )  //://////////////////////////://

        if( uint(0x000000) != pix_err ){

            #define F_F uint(0xFF)" //://////////////////////://
            pix_fra=( vec4(  //://///////////////////////////://

             float( ( pix_err >> 24  ) & F_F ) / 255.0
            ,float( ( pix_err >> 16  ) & F_F ) / 255.0
            ,float( ( pix_err >>  8  ) & F_F ) / 255.0
            ,float( ( pix_err >>  0  ) & F_F ) / 255.0

            ));; //://///////////////////////////////////////://
            #undef F_F  //://////////////////////////////////://

        };;

    #endif //:///////////////////////////////////////////////://


    //: Now in debug mode, you can color sample the pixel    ://
    //: and type in the hex code to find the exact error.    ://
    //: Might not be helpful for minor edge cases, but       ://
    //: should be very helpful for gross mistakes in         ://
    //: your programming logic.                              ://
    return( pix_fra );