Sketcher.cpp

#include <sdl/SDL.h>
#include "framework.h"
#include "video.h"
#include <math.h>
#include <stdio.h>

//
static sint32 pen_x, pen_y;

//
SDL_Surface *reference = NULL;

//
const bool cDrawCircles = false;
const int  cInterval   = 3000;
const int  cIterations = 32;
const int  cSamples    = 16;

//
int time = 0;

//
int iabs( int a )
{
    if ( a < 0 ) return -a;
                 return  a;
}

//
void loadFile( void )
{
    //
    char myPath[64] = { '\0' };
    //
    printf( "computer sketch - By 8BitPimp\nimage must be 32bit per pixel bitmap format\n" );
    //
    while ( true )
    {
        //
        printf( "please enter file name:\n" );
        //
        gets( myPath );
        //
        reference = SDL_LoadBMP( myPath );
        if ( reference != NULL )
            break;
        else
        {
            printf( "unable to load file!\n" );
            continue;
        }
    }
}

//
bool start_game( void )
{
    //
    loadFile( );
    //
    time = SDL_GetTicks( );
    //
    srand( time );
    //
    pen_x = (sint32)( rand() % _WIDTH  );
    pen_y = (sint32)( rand() % _HEIGHT );
    //
    return true;
}

//
float rand_angle( void )
{
    sint32 irand = ( rand() & (0x1000-1) ) - 0x800;
    float  frand = ((float)irand) / (float)0x800;
    //
    const float pi = 3.14159265359f;
    //
    return frand * pi;
}

//
float rand_length( float min, float max )
{
    float dif = max - min;
    //
    sint32 irand = ( rand() & (0x1000-1) ) - 0x800;
    float  frand = ((float)irand) / (float)0x800;
    //
    return min + frand * dif;
}

//
float rand_gauss( void )
{
    sint32 irand = ( rand() & (0x1000-1) ) - 0x800;
    float  frand = ((float)irand) / (float)0x800;
    //
    return frand * fabs( frand );
}

//
void randomisePen( void )
{
    float w = (float)(_WIDTH ) * 0.5f;
    float h = (float)(_HEIGHT) * 0.5f;
    pen_x = rand_gauss( ) * w + w;
    pen_y = rand_gauss( ) * h + h;
}

//
void keyhit_game( int sym )
{
    if ( sym == SDLK_c )    cls( 0x252525 );
    if ( sym == SDLK_r )    randomisePen( );
}

//
uint32 sample_colour( sint32 x, sint32 y )
{
    //
    if ( mouse.bchange[0] == 1 )
    {
        SDL_GetMouseState( &pen_x, &pen_y );
    }
    //
    if ( reference == NULL )
        return 0;
    //
    float  u  = (float)x / (float)_WIDTH ;
    float  v  = (float)y / (float)_HEIGHT;
    //
    sint32 i  = (sint32)( u * (float)reference->w );
    sint32 j  = (sint32)( v * (float)reference->h );
    //
    if ( i < 0 ) i = 0; if ( i >= reference->w ) i = reference->w-1;
    if ( j < 0 ) j = 0; if ( j >= reference->w ) j = reference->h-1;
    //
    if ( reference->format->BitsPerPixel == 32 )
    {
        uint32 *p = (uint32*)reference->pixels;
        return p[ i + j * (reference->pitch / sizeof( uint32 )) ];
    }
    if ( reference->format->BitsPerPixel == 24 )
    {
        return 0;
    }
    return 0;
}

//
bool tick_game( void )
{
    //
    int dif = SDL_GetTicks( ) - time;
    if ( dif > cInterval )
    {
        time += dif;
        randomisePen( );
    }
    //
    for ( int i=0; i<cIterations; i++ )
    {
        //
        while ( true )
        {
            //
            float length = rand_length( 4.0f, 24.0f );
            //
            int col = sample_colour( pen_x, pen_y );
            setColour( col );
            //
            sint32 new_x = pen_x;
            sint32 new_y = pen_y;
            bool not_set = true;
            //
            for ( int j=0; j<cSamples; j++ )
            {
                //
                float angle   = rand_angle( );
                float p_new_x = pen_x + (sint32)(length * sinf( angle ));
                float p_new_y = pen_y + (sint32)(length * cosf( angle ));
                //
                if ( p_new_x >= _WIDTH  ) continue;
                if ( p_new_y >= _HEIGHT ) continue;
                if ( p_new_x <= 0       ) continue;
                if ( p_new_y <= 0       ) continue;
                //
                int p_new_col = (col & 0xFF) - (sample_colour( p_new_x, p_new_y ) & 0xFF);
                int   new_col = (col & 0xFF) - (sample_colour(   new_x,   new_y ) & 0xFF);
                //
                if ( (iabs(p_new_col) < iabs(new_col)) || not_set )
                {
                    new_x = p_new_x;
                    new_y = p_new_y;
                    not_set = false;
                }
            }
            //
            if ( cDrawCircles )
            {
                int midx = (new_x + pen_x) / 2;
                int midy = (new_y + pen_y) / 2;
                drawCircle( midx, midy, length / 2 );
            }
            else
                drawLine( pen_x, pen_y, new_x, new_y );
            //
            pen_x = new_x;
            pen_y = new_y;
            //
            break;
        }
    }
    //
    SDL_Delay( 2 );
    //
    return true;
}

//
void finish_game( void )
{
}