//Update the screen
if( SDL_Flip( screen ) == -1 )
{
return 1;
} // end if
tetris in sdl
Author
I have decided to use sdl to display graphics for my tetris game. In text it all works perfect. I display each shape with a different number and then have a display function that goes through the game playing area and says if that spot has a 1 draw red block, if its a 2 draw green block and so on. I need help figuring out how to handle events. I need it to move left when the left arrow is pushed, right when the right arrow is pushed down when the down arrow is pushed and change the shape when the up arrow is pushed. I already did this in test using the w, a, s, d keys so i just need to create functions using sdl that will return true when the button is pushed. So i need a function that returns true when the up arrow is pushed, a function that returns true when the down arrow is pushed a function that returns true when the left arrow is pushed and a function that returns true when the right arrow is pushed. The SDL tutorials on the website use a case switch to detect which one has been pushed. I guess i could do that instead of if statements but i have it set up with if statements. Also another big problem i am having is when a shape is moved down the shape before it is not removed. I have the 2d int array that is my gameBoard change them back to 0 and then i loop through the entire gameBoard everytime something is moved and re-draw the shapes so why is it that when i move a piece from one spot to another even though the place in the array where the piece was is now 0 it does not clear those old blocks? This is my first time making anything graphical so any advice would be appreciated. I have everything figured out in the console using a 2d int array but i can't figure out the graphics part. Thanks.
EDIT: Also this sdl statement that updates the screen:
I am not sure where to put that. Should it go at the end of the function that draws the game board to the screen?
Author
ok so i might have spoken too soon. I us a case switch to detect when an arrow is pushed and it works fine. I still have 2 problems. 1 is the artifacts left on the screen when the piece moves and the other is with collision detection. It detects when it hits the edge fine but it does not detect when it hits a piece that is down. These 2 lead me to beleive that maybe the gameBoard is not being updated with 0 and non 0 correctly when i added the sdl parts for some reason. Here is all the code what do you think? Sorry its pretty long. The sdl parts are the parts im really having trouble with
#include "SDL/SDL.h"#include <string>#include <iostream>using namespace std;#define MIDDLE_X 6#define MIDDLE_Y 6#define TRUE 1#define FALSE 0#define WIDTH 17#define HEIGHT 17#define BLOCK_SIZE 30/************************************************ * function prototypes ************************************************/void moveRowsDown(void);void increaseLevel(void);/************************************************ * SDL Stuff * Initialize all SDL subsystems and window * function that loads the images * function that displays images to screen ************************************************///The attributes of the screenconst int SCREEN_WIDTH = 800;const int SCREEN_HEIGHT = 600;const int SCREEN_BPP = 32;//The surfaces that will be usedSDL_Surface *backwardL_block = NULL;SDL_Surface *longShank_block = NULL;SDL_Surface *lShape_block = NULL;SDL_Surface *square_block = NULL;SDL_Surface *tShape_block = NULL;SDL_Surface *zigZagRight_block = NULL;SDL_Surface *zigZagLeft_block = NULL;//SDL_Surface *background = NULL;SDL_Surface *screen = NULL;SDL_Surface *boarder_block = NULL;SDL_Event event;// load and optomize an image. Return the optomized imageSDL_Surface *loadImage( std::string filename ) { //Temporary storage for the image that's loaded SDL_Surface* loadedImage = NULL; //The optimized image that will be used SDL_Surface* optimizedImage = NULL; //Load the image loadedImage = SDL_LoadBMP( filename.c_str() ); //If nothing went wrong in loading the image if( loadedImage != NULL ) { //Create an optimized image optimizedImage = SDL_DisplayFormat( loadedImage ); //Free the old image SDL_FreeSurface( loadedImage ); } //Return the optimized image return optimizedImage;} // end loadImage// apply the surface to the screen at the x and y positions.void applySurface( int x, int y, SDL_Surface* source, SDL_Surface* destination ){ //Make a temporary rectangle to hold the offsets SDL_Rect offset; //Give the offsets to the rectangle offset.x = x; offset.y = y; //Blit the surface SDL_BlitSurface( source, NULL, destination, &offset );} // end applySurface// load the imagesvoid loadAllImages(){ backwardL_block = loadImage("bmp_blocks\\backwardL_block.bmp"); longShank_block = loadImage("bmp_blocks\\longShank_block.bmp"); lShape_block = loadImage("bmp_blocks\\lShape_block.bmp"); square_block = loadImage("bmp_blocks\\square_block.bmp"); tShape_block = loadImage("bmp_blocks\\tShape_block.bmp"); zigZagLeft_block = loadImage("bmp_blocks\\zigZagLeft_block.bmp"); zigZagRight_block = loadImage("bmp_blocks\\zigZagRight_block.bmp"); boarder_block = loadImage("bmp_blocks\\boarder_block.bmp"); //background = load_image( "background.bmp" );} // end loadAllImages// this initializes the SDL window and subsystem and all thatvoid initializeSDL(){ //Initialize all SDL subsystems if( SDL_Init( SDL_INIT_EVERYTHING ) == -1 ) { exit(1); } // end if //Set up the screen screen = SDL_SetVideoMode( SCREEN_WIDTH, SCREEN_HEIGHT, SCREEN_BPP, SDL_SWSURFACE ); //If there was in error in setting up the screen if( screen == NULL ) { exit(1); } // end if //Set the window caption SDL_WM_SetCaption( "My Tetris Game", NULL );} // end initializeSDL// this is called at the end, it frees up all the surfaces and quitsvoid cleanUp(){ //Free the surfaces SDL_FreeSurface(longShank_block); SDL_FreeSurface(backwardL_block); SDL_FreeSurface(square_block); SDL_FreeSurface(tShape_block); SDL_FreeSurface(lShape_block); SDL_FreeSurface(boarder_block); SDL_FreeSurface(zigZagLeft_block); SDL_FreeSurface(zigZagRight_block); //Quit SDL SDL_Quit();} // end cleanUp/************************************************ * End SDL Stuff ************************************************/int shape;int rotation;int xPos;int yPos;int collideDown = FALSE;int score;int level;int lines;bool gameOver = false;/************************************************ * main game board ************************************************/int gameBoard[HEIGHT][WIDTH] = {{8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8}, {8, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8}, {8, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8}, {8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8}, {8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8}, {8, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8}, {8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8}, {8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8}, {8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8}, {8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8}, {8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8}, {8, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8}, {8, 0, 0, 0, 2, 2, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 8}, {8, 0, 0, 0, 0, 2, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 8}, {8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8}, {8, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 8}, {8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8}, };// 0 out gameBoard()void resetGameBoard(){ for (int row = 1; row < HEIGHT-1; row++) { for (int col = 1; col < WIDTH-1; col++) gameBoard[row][col] = 0; } // end for} // end resetGameBoard/*void displayGameBoard(){ for (int row = 0; row < HEIGHT; row++) { for (int col = 0; col < WIDTH; col++) cout << gameBoard[row][col]; cout << endl; } // end for} // end displayGameBoard*/void displayGameBoard(){ for (int row = 0; row < HEIGHT; row++) { for (int col = 0; col < WIDTH; col++) { if (gameBoard[row][col] == 1) applySurface(col*BLOCK_SIZE, row*BLOCK_SIZE, longShank_block, screen); else if (gameBoard[row][col] == 2) applySurface(col*BLOCK_SIZE, row*BLOCK_SIZE, tShape_block, screen); else if (gameBoard[row][col] == 3) applySurface(col*BLOCK_SIZE, row*BLOCK_SIZE, square_block, screen); else if (gameBoard[row][col] == 4) applySurface(col*BLOCK_SIZE, row*BLOCK_SIZE, backwardL_block, screen); else if (gameBoard[row][col] == 5) applySurface(col*BLOCK_SIZE, row*BLOCK_SIZE, zigZagLeft_block, screen); else if (gameBoard[row][col] == 6) applySurface(col*BLOCK_SIZE, row*BLOCK_SIZE, zigZagRight_block, screen); else if (gameBoard[row][col] == 7) applySurface(col*BLOCK_SIZE, row*BLOCK_SIZE, lShape_block, screen); else if (gameBoard[row][col] == 8) applySurface(col*BLOCK_SIZE, row*BLOCK_SIZE, boarder_block, screen); } // end for } // end for} // end displayGameBoard/************************************************ * end main game board ************************************************//************************************************ * array that holds all the shapes ************************************************/int shapeArray[7][4][4][4] ={ { { {0, 0, 1, 0}, {0, 0, 1, 0}, {0, 0, 1, 0}, {0, 0, 1, 0} }, { {0, 0, 0, 0}, {0, 0, 0, 0}, {1, 1, 1, 1}, {0, 0, 0, 0} }, { {0, 1, 0, 0}, {0, 1, 0, 0}, {0, 1, 0, 0}, {0, 1, 0, 0} }, { {0, 0, 0, 0}, {1, 1, 1, 1}, {0, 0, 0, 0}, {0, 0, 0, 0} } } , { { {0, 0, 0, 0}, {0, 2, 2, 2}, {0, 0, 2, 0}, {0, 0, 0, 0} }, { {0, 0, 0, 0}, {0, 0, 2, 0}, {0, 2, 2, 0}, {0, 0, 2, 0} }, { {0, 0, 0, 0}, {0, 2, 0, 0}, {2, 2, 2, 0}, {0, 0, 0, 0} }, { {0, 2, 0, 0}, {0, 2, 2, 0}, {0, 2, 0, 0}, {0, 0, 0, 0} } } , { { {0, 0, 0, 0}, {0, 3, 3, 0}, {0, 3, 3, 0}, {0, 0, 0, 0} }, { {0, 0, 0, 0}, {0, 3, 3, 0}, {0, 3, 3, 0}, {0, 0, 0, 0} }, { {0, 0, 0, 0}, {0, 3, 3, 0}, {0, 3, 3, 0}, {0, 0, 0, 0} }, { {0, 0, 0, 0}, {0, 3, 3, 0}, {0, 3, 3, 0}, {0, 0, 0, 0} } } , { { {0, 0, 0, 0}, {0, 4, 4, 4}, {0, 0, 0, 4}, {0, 0, 0, 0} }, { {0, 0, 0, 0}, {0, 0, 4, 0}, {0, 0, 4, 0}, {0, 4, 4, 0} }, { {0, 0, 0, 0}, {4, 0, 0, 0}, {4, 4, 4, 0}, {0, 0, 0, 0} }, { {0, 4, 4, 0}, {0, 4, 0, 0}, {0, 4, 0, 0}, {0, 0, 0, 0} } } , { { {0, 0, 0, 0}, {0, 5, 5, 0}, {0, 0, 5, 5}, {0, 0, 0, 0} }, { {0, 0, 0, 0}, {0, 0, 5, 0}, {0, 5, 5, 0}, {0, 5, 0, 0} }, { {0, 0, 0, 0}, {5, 5, 0, 0}, {0, 5, 5, 0}, {0, 0, 0, 0} }, { {0, 0, 5, 0}, {0, 5, 5, 0}, {0, 5, 0, 0}, {0, 0, 0, 0} } } , { { {0, 0, 0, 0}, {0, 0, 6, 6}, {0, 6, 6, 0}, {0, 0, 0, 0} }, { {0, 0, 0, 0}, {0, 6, 0, 0}, {0, 6, 6, 0}, {0, 0, 6, 0} }, { {0, 0, 0, 0}, {0, 6, 6, 0}, {6, 6, 0, 0}, {0, 0, 0, 0} }, { {0, 6, 0, 0}, {0, 6, 6, 0}, {0, 0, 6, 0}, {0, 0, 0, 0} } } , { { {0, 0, 0, 0}, {0, 7, 7, 7}, {0, 7, 0, 0}, {0, 0, 0, 0} }, { {0, 0, 0, 0}, {0, 7, 7, 0}, {0, 0, 7, 0}, {0, 0, 7, 0} }, { {0, 0, 0, 0}, {0, 0, 7, 0}, {7, 7, 7, 0}, {0, 0, 0, 0} }, { {0, 7, 0, 0}, {0, 7, 0, 0}, {0, 7, 7, 0}, {0, 0, 0, 0} } }};/************************************************ * end array that holds all the shapes ************************************************//************************************************ * Tetris game logic functions * These functions have all the logic of * playing Tetris ************************************************/// put the piece on the gameBoardvoid putPieceOnBoard(){ for (int r = 0; r < 4; ++r) for (int c = 0; c < 4; ++c) if (shapeArray[shape][rotation][r][c] != 0) gameBoard[yPos+r][xPos+c] = shape+1;} // end putPieceOnBoardvoid removePieceFromBoard(){ for (int r = 0; r < 4; ++r) for (int c = 0; c < 4; ++c) if (shapeArray[shape][rotation][r][c] != 0) gameBoard[yPos+r][xPos+c] = 0;} // end removePieceFromBoard// check if there is a collisionbool checkCollision(){ for (int r = 0; r < 4; ++r) for (int c = 0; c < 4; ++c) { if ( (gameBoard[r+yPos][c+xPos] != 0) && (shapeArray[shape][rotation][r][c] != 0) ) // There's overlap return true; } // end for return false;} // end checkCollision/*// this returns the next random shapevoid nextShape(){ shape = rand() % 7; //return shape;} // end nextShape*/// gets the next piece, sets rotation and x and y cordinatesvoid nextShape(){ shape = rand() % 7; rotation = 0; xPos = MIDDLE_X; //or wherever the middle of your board is yPos = 0; if (checkCollision()) { gameOver = true; cout << "The game is over!\n"; } // end if} // end nextPiece// this returns the next rotation// it sets the rotation to either a 0, 1, 2, or 3void rotate(){ rotation = (rotation + 1) & 3; if (checkCollision()) rotation = (rotation - 1) & 3;} // end rotate// try to move left, move back if you can'tvoid tryToMoveLeft(){ --xPos; if (checkCollision()) ++xPos;} // end tryToMoveLeft// try to move right, move back if you can'tvoid tryToMoveRight(){ ++xPos; if (checkCollision()) --xPos;} // end tryToMoveRight// try to move down, move back if you can'tvoid tryToMoveDown(){ ++yPos; if (checkCollision()) { --yPos; collideDown = TRUE; } // end if} // end tryToMoveDown// rotate if you can, if you can't go back to old rotationvoid tryToRotate(){ int oldRotation = rotation; rotation = (rotation + 1) & 3; if (checkCollision()) { rotation = oldRotation; cout << "inside this if statement\n"; } // end if cout << "the rotation inside the function is " << rotation << endl;} // tryToRotate// return true if the row is full and needs to be deleted, false otherwisebool isRowFull(int row){ int rowFull = 0; for (int col = 0; col < WIDTH; col++) { if (gameBoard[row][col] != 0) { rowFull++; cout << "Row full is " << rowFull << endl; cout << "row is : " << row << endl; } // end if } // end for if (rowFull == 17) { cout << "row is full\n"; return true; } // end if else { cout << "row is not full\n"; return false; } // end else} // end isRowFull// test the row full function fill up a row with 1's and see if it returns true;void fillRow(int row){ for (int col = 1; col < WIDTH-1; col++) { gameBoard[row][col] = 1; } // end for} // end fillRow// unfill 1 rowvoid unFillOneRow(int row){ for (int col = 1; col < WIDTH-1; col++) gameBoard[row][col] = 0;} // end unFillOneRow void moveRowsDown(int n){ int row; for (row = n; row > 1; row--) { for (int col = 1; col < WIDTH-1; col++) { //cout << "the row is : " << row << endl; //cout << "the col is : " << col << endl; gameBoard[row][col] = gameBoard[row-1][col]; } // end for } // end for cout << "the row is " << row << endl; // this sets the first row to 0's unFillOneRow(1);} // end moveRowsDown/*void arrangeRows(int y){ for (int i = 0; i < 4; i++) { cout << "Y = " << y << endl; if (isRowFull(y)) { cout << "Y = " << y << endl; moveRowsDown(y); lines++; cout << "line count is " << lines << endl; increaseLevel(); cout << "level is " << level << endl; } // end if else y = y - 1; } // end for} // end arrangeRows*/void arrangeRows(){ for (int row = 1; row < WIDTH-1; row++) { if (isRowFull(row)) { moveRowsDown(row); lines = lines + 1; cout << "line count is " << lines << endl; increaseLevel(); cout << "level is " << level << endl; score = score + 100; cout << "score is " << score << endl; } // end if } // end for} // end arrangeRows// increment level if it needs to bevoid increaseLevel(){ if (lines == 10) level = level + 1;} // end increaseLevel/************************************************ * end array that holds all the shapes ************************************************/// the main methodint main( int argc, char* args[] ){ bool quit = false; initializeSDL(); loadAllImages(); resetGameBoard(); displayGameBoard(); // main game loop while(quit == false) { putPieceOnBoard(); //If there's an event to handle if( SDL_PollEvent( &event ) ) { //If a key was pressed if( event.type == SDL_KEYDOWN ) { //Set the proper message surface switch( event.key.keysym.sym ) { case SDLK_UP: removePieceFromBoard(); tryToRotate(); putPieceOnBoard(); displayGameBoard(); //Update the screen if( SDL_Flip( screen ) == -1 ) { return 1; } // end if break; case SDLK_DOWN: removePieceFromBoard(); tryToMoveDown(); if (collideDown == TRUE) { // do all the level and line checks in here arrangeRows(); nextShape(); rotation = 0; xPos = MIDDLE_X; yPos = 0; collideDown = FALSE; continue; } // end if putPieceOnBoard(); displayGameBoard(); if( SDL_Flip( screen ) == -1 ) { return 1; } // end if break; case SDLK_LEFT: removePieceFromBoard(); tryToMoveLeft(); putPieceOnBoard(); displayGameBoard(); if( SDL_Flip( screen ) == -1 ) { return 1; } // end if break; case SDLK_RIGHT: removePieceFromBoard(); tryToMoveRight(); putPieceOnBoard(); displayGameBoard(); //Update the screen if( SDL_Flip( screen ) == -1 ) { return 1; } // end if break; } // end switch } // end if //If the user has Xed out the window else if( event.type == SDL_QUIT ) { //Quit the program quit = true; } // end else if } // end if } // end while/* displayGameBoard(); nextShape(); putPieceOnBoard(); SDL_Delay(200); displayGameBoard(); //Update the screen if( SDL_Flip( screen ) == -1 ) { return 1; } // end if removePieceFromBoard(); SDL_Delay(200); while (collideDown == FALSE) { removePieceFromBoard(); displayGameBoard(); tryToMoveDown(); putPieceOnBoard(); displayGameBoard(); } //end while*/ //Update the screen if( SDL_Flip( screen ) == -1 ) { return 1; } // end if //Wait 2 seconds // SDL_Delay(20000); cleanUp(); return 0; }
It doesn't really sound like you have a game loop at all. The common SDL game loop is along these lines:
Your other option I suppose is to do something like this:
This code:
does one of two things, on a double buffered window it will swap the front and back buffers, and on a single buffered window it will update the screen. Double buffering means that everything is drawn to a hidden buffer, then all drawn to the screen at one time, to prevent tearing and such.
EDIT: Answered too soon, sorry I am at work I do not have time to go through all of that code. You may want to learn SDL before you attempt a game though.
while(game_is_running == 1){ SDL_Event event; while(SDL_PollEvent(&event)) { switch(event.type) { case SDL_QUIT: game_is_running = 0; break; case SDL_KEYDOWN: switch(event.key.keysym.sym) { case SDLK_ESCAPE: game_is_running = 0; break; case SDLK_UP: //handle up break; //handle other keys also } break; } } //update logic //draw scene SDL_Flip(screen);}Your other option I suppose is to do something like this:
Uint8 * key_state = SDL_GetKeyState();while(game_is_running == 1){ SDL_PumpEvents(); if(key_state[SDLK_UP]) { //handle up key } //update logic //draw scene SDL_Flip(screen);}This code:
if( SDL_Flip( screen ) == -1 ){ return 1; }does one of two things, on a double buffered window it will swap the front and back buffers, and on a single buffered window it will update the screen. Double buffering means that everything is drawn to a hidden buffer, then all drawn to the screen at one time, to prevent tearing and such.
EDIT: Answered too soon, sorry I am at work I do not have time to go through all of that code. You may want to learn SDL before you attempt a game though.
Author
O ok thanks, i've never written a "game loop" before so i'll switch it to that. Would that take care of the collision problems and the artifact problems though? I have heard of double buffering but don't know how i would do it or if i have to do it. Well i know some SDL. How to set up a window, how to draw things. I thought if i used an int array for the game board and pieces on the game board that i would not need to use the graphics for any of the logic really. All the graphics would be is a way to display it to the screen. All the logic would be using the 2d int array and it kinda works.
Author
I think the problem is that the gameBoard for some reason does not update correctly because the only collisions that get detected are when it hits bottom. But just using text it gets updated and really the only thing im using sdl for is to display the blocks so what in sdl could stop it from updating the gameBoard correctly? I changed 1 function from the text version to the graphics version and that is the display method and that does not modify the game board array at all. So why does it not work now?
Author
I was just reading about capping frame rate in sdl. Is it because right now i update the screen every time a piece is moved when i should be updating the screen every frame? If i need to update the screen every frame how do i even know when a frame has passed?
Quote:If i need to update the screen every frame how do i even know when a frame has passed?As Portmanteau related, the game loop does it's thing in, well, a loop. That means that it goes though everything in the loop in order from top to bottom. Your "frame" ends when you reach the end of the code segment since this is the point right before it goes back to the top to start all over again.
As for frame rates, some people consider capping the frame rate poor practice. I just consider it unnecessary. In a game like tetris, everything is time based so just measure the time between frames (SDL_GetTicks() should do the trick) and update the game based on how much time has passed. For instance, a piece falls 1 level every second - after 1 second has passed change the level of the block.
Just an idea but consider the following:
// globals or whatever to get the point acrossint iLevelDropTime = 1000; // 1 second = 1000 millisecondsint iDropCounter = 0;int iNowTime, iLastTime = SDL_GetTicks();while( game_is_running ){ // store the start time of the frame iNowTime = SDL_GetTicks(); // get your input HandleInput(); // Update the drop timer iDropCounter += iNowTime - iLastTime; // see if we need to drop the piece // using while in case for some reason the frame took an extra long // amount of time while ( iDropCounter >= iLevelDropTime ) { DropPieceLevel(); iDropCounter -= iLevelDropTime; } // update the screen DrawStuff(); SDL_Flip( SDL_GetVideoSurface() ); // update the iLastTime variable with when this frame started // when the loop starts again iNowTime - iLastTime will be the // time it took to complete this frame iLastTime = iNowTime;}
Author
i think that will work but my program flow is a bit different. I update the board more i think. You have it as get input, update drop timer update screen. My loop is more check for all input and when an input is gotten, so moving a piece, the screen is updated. Here is my "game loop" when would i update to have the timer and whatnot cause i really don't know what im doing with this kind of stuff at all.
//While the user hasn't quit while( quit == false ) { displayGameBoard(); putPieceOnBoard(); iNowTime = SDL_GetTicks(); //While there's events to handle while( SDL_PollEvent( &event ) ) { //If the user has Xed out the window if( event.type == SDL_QUIT ) { //Quit the program quit = true; } // end if } // end while //Get the keystates Uint8 *keystates = SDL_GetKeyState( NULL ); //If up is pressed if( keystates[ SDLK_UP ] ) { removePieceFromBoard(); tryToRotate(); putPieceOnBoard(); displayGameBoard(); } // end if //If down is pressed if( keystates[ SDLK_DOWN ] ) { removePieceFromBoard(); tryToMoveDown(); if (collideDown == TRUE) { // do all the level and line checks in here putPieceOnBoard(); arrangeRows(); nextShape(); collideDown = FALSE; continue; } // end if putPieceOnBoard(); displayGameBoard(); displayGameBoardCons(); } // end if //If left is pressed if( keystates[ SDLK_LEFT ] ) { removePieceFromBoard(); tryToMoveLeft(); putPieceOnBoard(); displayGameBoard(); displayGameBoardCons(); } // end if //If right is pressed if( keystates[ SDLK_RIGHT ] ) { removePieceFromBoard(); tryToMoveRight(); putPieceOnBoard(); displayGameBoard(); displayGameBoardCons(); } // end if // Update the drop timer iDropCounter += iNowTime - iLastTime; // see if we need to drop the piece // using while in case for some reason the frame took an extra long // amount of time while ( iDropCounter >= iLevelDropTime ) { tryToMoveDown(); iDropCounter -= iLevelDropTime; } iLastTime = iNowTime; } // end while
Author
ok i got it to go down by itself. But now my question is which variable would i increment when the level increases to make it fall faster?
You would decrease the iLevelDropTime variable making the time before the piece drops shorter.
You should make sure you understand what is going on in the game loop before going much further as it won't get any simpler than it already is. Try walking through each line of code in the game loop and figuring out why that line is there as opposed to somewhere else and what does it actually accomplish.
You should make sure you understand what is going on in the game loop before going much further as it won't get any simpler than it already is. Try walking through each line of code in the game loop and figuring out why that line is there as opposed to somewhere else and what does it actually accomplish.
This topic is closed to new replies.
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