tetris/Logic/TetrisGame.cpp

/*
 * TetrisGame.cpp
 *
 *  Created on: May 5, 2013
 *      Author: chibi_000
 */

#include "TetrisGame.h"
#include <math.h>

TetrisGame::TetrisGame(int w, int h, const PieceGenerator& pg)
	: grid(w, h), gen(pg)
{
	this->score = 0;
	this->level = 1;
	this->cx = 0;
	this->cy = 0;
	this->next = gen.getRandomPieceRotated();

	this->pickNextPiece();
}

TetrisGame::~TetrisGame()
{
}

int TetrisGame::xToPiece(int x_g)
{
	return x_g - cx;
}

int TetrisGame::xToGrid(int x_p)
{
	return x_p + cx;
}

int TetrisGame::yToPiece(int y_g)
{
	return y_g - cy;
}

int TetrisGame::yToGrid(int y_p)
{
	return y_p + cy;
}

void TetrisGame::pickNextPiece()
{
	// Next becomes current
	this->current = this->next;

	// Pick a new piece
	this->next = gen.getRandomPieceRotated();

	// Set position to middle center
	this->cy = -this->current.getHeight();
	this->cx = ( grid.getWidth() - current.getWidth() ) / 2;
}


void TetrisGame::putPieceInGrid()
{
	for (int x = 0; x < current.getWidth(); x++)
		for (int y = 0; y < current.getHeight(); y++)
			grid.set( xToGrid(x), yToGrid(y), grid.get( xToGrid(x), yToGrid(y) ) + current.get(x, y) );
}

int TetrisGame::markFullLines()
{
	int total_rows = 0;

	// For each row
	for (int y = 0; y < grid.getHeight(); y++)
	{
		// Count non-empty cells
		int count = 0;

		for (int x = 0; x < grid.getWidth(); x++)
			count += ( grid.get(x, y) > 0 ) ? 1 : 0;

		// Count equal to width = full line
		if (count == grid.getWidth())
		{
			total_rows++;

			for (int x = 0; x < grid.getWidth(); x++)
				grid.set(x, y, -1);
		}
	}

	// Return found rows
	return total_rows;
}

void TetrisGame::removeFullLines()
{
	for (int yto = grid.getHeight()-1, yfrom = yto; yto >= 0; yto--, yfrom--)
	{
		// Skip full lines
		while (grid.get(0, yfrom) == -1 && yfrom >= 0)
			yfrom--;

		// Remove content
		for (int x = 0; x < grid.getWidth(); x++)
			if (yfrom < 0)
				grid.set(x, yto, 0);
			else
				grid.set(x, yto, grid.get(x, yfrom));
	}
}

bool TetrisGame::isGameOver()
{
	for (int x = 0; x < grid.getWidth(); x++)
		if (grid.get(x, 0) != 0)
			return true;

	return false;
}

bool TetrisGame::collides(int cx, int cy, const Piece& p)
{
	// Check bounds
	if (cx < 0 || cx + p.getWidth() > grid.getWidth())
		return true;

	if (cy + p.getHeight() > grid.getHeight())
		return true;

	// Check every piece
	for (int x = 0; x < p.getWidth(); x++)
		for (int y = 0; y < p.getHeight(); y++)
			if ( y+cy >= 0 && p.get(x, y) != 0 && grid.get(x+cx, y+cy) != 0 )
				return true;

	return false;
}

bool TetrisGame::collidesDown()
{
	return this->collides(cx, cy+1, current);
}

bool TetrisGame::collidesLeft()
{
	return this->collides(cx-1, cy, current);
}

bool TetrisGame::collidesRight()
{
	return this->collides(cx+1, cy, current);
}

void TetrisGame::moveLeft()
{
	if (!this->collidesLeft())
		this->cx--;
}

void TetrisGame::moveRight()
{
	if (!this->collidesRight())
		this->cx++;
}

void TetrisGame::moveDown()
{
	while (!this->collidesDown())
		this->cy++;
}

void TetrisGame::rotate()
{
	Piece rot = current.rotate();

	if (!this->collides(cx, cy, rot))
		current = rot;
}

void TetrisGame::tick()
{
	// Check if game is over
	if (this->isGameOver())
		return;

	// Remove full lines
	this->removeFullLines();

	// Piece is down
	if (this->collidesDown())
	{
		this->putPieceInGrid();
		this->pickNextPiece();

		int count = this->markFullLines();

		// Calculate score
		this->score += (1<<(count - 1)) * 100;
		if (this->score > (1<<(level - 1)) * 5000)
			this->level++;
	}

	// Piece is not down, simply move it
	else this->cy++;
}

int TetrisGame::get(int x, int y)
{
	bool col = cx <= x && x < cx + current.getWidth();
	bool row = cy <= y && y < cy + current.getHeight();

	if (col && row)
		return grid.get(x, y) + current.get( xToPiece(x), yToPiece(y) );

	return grid.get(x, y);
}

Piece TetrisGame::getNextPiece()
{
	return next;
}

int TetrisGame::getScore()
{
	return score;
}

int TetrisGame::getLevel()
{
	return level;
}

int TetrisGame::getTickTime()
{
	float l = sqrtf(this->level);
	return 800 / l;
}