SDF-018-BUFFER

//[ THIS_FILE_IS[ SDF_018.BUFFER._ ]                 ]//
/** ************************************************ ***
***                                                  ***
***     Live Stream Of Me Working On This Code:      ***
***                                                  ***
*** ************************************************ ***

                twitch.com/kanjicoder

*** ************************************************ ***
***                                                  ***
*** SELF___________URL:  tinyurl.com/SDF-018-BUFFER  ***
*** DOCUMENTATION__URL:  tinyurl.com/SDF-018         ***
*** SOURCE_CODE_BUFFER:  tinyurl.com/SDF-018-BUFFER  ***
*** SOURCE_CODE__IMAGE:  tinyurl.com/SDF-018-IMAGE   ***
*** LIVE__________DEMO:  tinyurl.com/SDF-018-DEMO    ***
*** SETUP________VIDEO:  tinyurl.com/SDF-018-SETUP   ***
***                                                  ***
*** ************************************************ **/
//:INSTRUCTIONS:IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII://
/** ************************************************ ***

    Click And Drag on the canvas to set pixels.

*** ************************************************ **/
//:IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII:INSTRUCTIONS://
//:MACROS:MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM://

    #define IV2 ivec2
    #define V_4  vec4
    #define V_3  vec3
    #define V_2  vec2
    #define F32 float
    #define I32   int
    #define U32  uint

//:MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM:MACROS://
//:DATA:DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD://

    //:NO DATA

//:DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD:DATA://
//:FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF://
//:FUNCTIONS:BELOW:____DO_NOT_INDENT____OUTER_SCOPE!!://
//:FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF://

void mainImage( out vec4 fragColor, in vec2 fragCoord )
{
    V_4 c4d;

    IV2 f_c = IV2( I32( fragCoord.x - 0.5 ) ,
                   I32( fragCoord.y - 0.5 ) );;

    //:Initialize Data?
    V_4 rfp = texelFetch( iChannel0 ,ivec2(127,127),0);
    U32 rfb = U32( rfp.w * 255.0 );
    if( rfb >= U32( 1 ) ){

        c4d = texelFetch( iChannel0 , f_c , 0 );

    }else{
        if( f_c.x != 127 && f_c.y != 127 ){
            c4d=vec4(1.0,1.0,1.0    ,1);
        }else{
            c4d=vec4(1.0,1.0,1.0    ,1);
        };;
    };;

    //:Set [pixel/tile] ?
    if( iMouse.z > 0.0 ){ //:Mouse Down?
    if( I32( iMouse.x ) == f_c.x ){
    if( I32( iMouse.y ) == f_c.y ){


        c4d=vec4( 0,0,1  ,1);

    };;};;};;


    fragColor = c4d;

}

//:FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF://
//:FUNCTIONS:ABOVE:____DO_NOT_INDENT____OUTER_SCOPE!!://
//:FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF://
//:MACROS:MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM://

    #undef  IV2
    #undef  V_4
    #undef  V_3
    #undef  V_2
    #undef  F32
    #undef  I32
    #undef  U32

//:MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM:MACROS://