QUORA_GRAPHICS_QUESTION

    #include <stdint.h>

    //:For Example, in non-toy code don't allocate on
    //:the stack like this.
    #define WID  32
    #define HIG  64
    #define RGBA  4
    uint8_t img[ WID * HIG * RGBA ]={ 0 };

    //:Y loop on outside to traverse pixels in order,
    //:which should help prevent cache misses.
    for( int y = 0 ; y <=( HIG-1 ) ; y ++ ){
    for( int x = 0 ; x <=( WID-1 ) ; x ++ ){

        //: xy to index formula ://
        int  i =( x + ( y * WID ) );

        //:Set a pixel:
        img[ (i*RGBA)+0 ]=( 0xFF ) ; //:Set Red  ://
        img[ (i*RGBA)+1 ]=( 0x44 ) ; //:Set Green://
        img[ (i*RGBA)+2 ]=( 0x12 ) ; //:Set Blue ://
        img[ (i*RGBA)+3 ]=(  255 ) ; //:Set Alpha://

    };;};;