File content as of revision 9:dc13042b09f5:

#include "engine.h"

Engine::Engine(){
    
    
}

Engine::~Engine(){
    
}

void Engine::init(int screenHeight, int screenWidth, int speed){

    setSpeed(speed);
    _screen_height = screenHeight;
    _screen_width = screenWidth;
    _car_positon = 0.0f; 
    _distance = 0.0f;
    _curvature = 0.0f;
    
    MapSegment seg1;
    seg1.curvature = 0.0f;
    seg1.meters = 100.0f;
    track.push_back(seg1);
    
    MapSegment seg2;
    seg2.curvature = -1.0f;
    seg2.meters = 200.0f;
    track.push_back(seg2);
    
    MapSegment seg3;
    seg3.curvature = 1.0f;
    seg3.meters = 200.0f;
    track.push_back(seg3);   
    
    MapSegment seg4;
    seg4.curvature = -1.0f;
    seg4.meters = 200.0f;
    track.push_back(seg4); 
    
    MapSegment seg5;
    seg5.curvature = 1.0f;
    seg5.meters = 200.0f;
    track.push_back(seg5); 
}

void Engine::setSpeed(int speed) {
    if (speed <= 0) _speed = 0;
    
    _speed = speed;
}

void Engine::update(Gamepad &pad, N5110 &lcd, float elapsedTime) {
    
    clearScreen(lcd);
     if(pad.get_direction() == N) {
            _speed += 2.0f * elapsedTime;
    }
    else 
        _speed -= 1.0f * elapsedTime;
        
    // clamp speed
    if ( _speed < 0.0f) _speed = 0.0f;
    if ( _speed > 1.0f) _speed = 1.0f;
    
    _distance += (_speed * 110.0f) * elapsedTime;
    
    // get point on track 
    float foffset = 0;
    int ntrackSection = 0;
    
    // find position on track
    while( ntrackSection < track.size() && foffset < _distance){
     
        foffset += track[ntrackSection].meters;
        ntrackSection++; 
    }
    
    float targetCurvature = track[ntrackSection -1].curvature;
    
    float curvDiff = (targetCurvature - _curvature) * elapsedTime;
    _curvature += curvDiff;
    
    
    for (int y = 0; y < _screen_height / 2; y++) {
        
         //_distance += n;
            
        float fPerspective = (float)y / (_screen_height / 2.0f);
        
        for (int x = 0; x < _screen_width; x++) {
            
           
            
            float fPointCentre = 0.5f + _curvature * powf((1.0f - fPerspective), 3);
            float fRoadSpace = 0.1f + fPerspective * 0.8f;
            float fSideSpace = fRoadSpace * 0.15f;
            
            // for easier calculating the sides
            fRoadSpace *= 0.5f;
            
            int leftGrass = (fPointCentre - fRoadSpace - fSideSpace) * _screen_width;
            int leftSide = (fPointCentre - fRoadSpace) * _screen_width;
            int rightGrass = (fPointCentre + fRoadSpace + fSideSpace) * _screen_width;
            int rightSide = (fPointCentre + fRoadSpace) * _screen_width;
            
            int row = _screen_height / 2 + y;
            
            float GrassColour = sinf(20.0f * powf(1.0f - fPerspective, 3) + _distance * 0.1f);
            if (GrassColour > 0.0f) GrassColour = 1.0f;
            else GrassColour = 0.0f;
            
            float SideColour = sinf(40.0f * powf(1.0f - fPerspective, 3) + _distance * 0.1f);
            if (SideColour > 0.0f) SideColour = 1.0f;
            else SideColour = 0.0f;
            
            if ( x >= 0 && x < leftGrass) {
                if ( GrassColour == 0.0f ) 
                lcd.setPixel(x, row, true);
            } 
            if ( x >= leftGrass && x < leftSide) {
                if ( x % 2 ==0)
                    if ( SideColour == 0.0f ) 
                        lcd.setPixel(x, row, true);
            }
            if ( x >= rightSide && x < rightGrass ) {
                if ( x % 2 ==0)
                     if ( SideColour == 0.0f ) 
                        lcd.setPixel(x, row, true);
            } 
            if ( x >= rightGrass && x < _screen_width) {
                if ( GrassColour == 0.0f ) 
                lcd.setPixel(x, row, true);
            }        
        }
    }
    // draw car
    int nCarPosition = _screen_width / 2 + ((int)_screen_width * _car_positon / 2.0f) - 9;
    
    lcd.drawSprite(nCarPosition, 36, 6, 9, car1);
    lcd.refresh();
   
}

int Engine::car1[6*9] = {
        0,0,0,0,1,0,0,0,0,
        0,0,0,1,1,1,0,0,0,
        0,0,0,1,1,1,0,0,0,
        1,0,1,1,1,1,1,0,1,
        1,1,1,1,1,1,1,1,1,
        0,0,0,1,0,1,0,0,0
    };
    
int Engine::car2[6*9] = {
        0,0,1,0,0,1,1,0,0,
        0,1,0,0,1,1,1,0,0,
        0,1,1,1,1,1,0,0,0,
        1,0,1,1,1,0,0,0,0,
        0,0,0,1,1,1,1,0,0,
        0,0,1,0,0,0,0,0,0
    };
    
 int Engine::car3[6*9] = {
        0,0,1,1,0,0,1,0,0,
        0,0,1,1,1,0,0,1,0,
        0,0,0,1,1,1,1,1,0,
        0,0,0,0,1,1,1,0,1,
        0,0,1,1,1,1,0,0,0,
        0,0,0,0,0,0,1,0,0
     };