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qhash

OpenGL [n00b] moving objects in OpenGL , Tetris

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qhash    122
hi I am new here and OpenGL is also new for me ;) I already can initialize, draw , resize windows , make perspective in OpenGL , but i dont know how to move objects. This is a big problem , beacouse i am writing tetris. Could someone send me a simple code showing how to make moving 2D cubes , adding new ones to the scene , in order to make my game working. I searched the net and didnt find anything useful for me :(

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Ademan555    361
look up matrix transformations, glTranslatef() is what you need, as for handling your blocks, youll need to devise your own way to hang on to your current blocks and keep adding one (for now a std::list will serve you well)

hope that helps a bit
-Dan

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qhash    122
big thx for help , especially that link to nehe page

and if someone has his own sourcecode of tetris i will of sharing it , possibly will help me a lot
[ not whole , simply a way that moving blocks is implemented ]

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zedzeek    529
hehe the date of this file is 3/7/2000, its 4 years and a day old, man i was a crap programmeur then


#include "main.h"

float currentTick, lastTick, totalTime;

float fps;

// this sets up the various shapes of the bricks

void brick_sort::setup_areas(int *places)
{ for (int rot=0;rot<4;rot++)
{ for (int i=0;i<8;i++)
{ if (i%2)
area[i/2][rot].y=places[i+rot*8];
else
area[i/2][rot].x=places[i+rot*8];
}
}
}

Game::Game()
{
}

int areas[] = {0,0,1,0,0,1,1,1, 0,0,1,0,0,1,1,1, 0,0,1,0,0,1,1,1, 0,0,1,0,0,1,1,1, // SQUARE
0,0,-1,0,0,1,1,0, 0,0,-1,0,0,1,0,-1, 0,0,-1,0,0,-1,1,0, 0,0,0,1,0,-1,1,0, // TSHAPE
0,0,-1,0,0,1,1,1, 0,0,0,1,1,0,1,-1, 0,0,-1,0,0,1,1,1, 0,0,0,1,1,0,1,-1, // ZSHAPELEFT
0,0,-1,1,0,1,1,0, 0,0,0,-1,1,0,1,1, 0,0,-1,1,0,1,1,0, 0,0,0,-1,1,0,1,1, // ZSHAPERIGHT
0,0,-1,0,1,0,2,0, 0,0,0,-1,0,-2,0,1, 0,0,-1,0,1,0,2,0, 0,0,0,-1,0,-2,0,1, // LONGONE
0,0,0,1,0,-1,1,-1, 0,0,-1,0,1,0,1,1, 0,0,-1,1,0,1,0,-1, 0,0,-1,0,1,0,-1,-1, // LLEFT
0,0,0,1,-1,-1,0,-1, 0,0,-1,0,1,0,1,-1, 0,0,0,1,1,1,0,-1, 0,0,-1,1,-1,0,1,0};// LRIGHT

float colours[] = {1,0,0, 1,1,0, 0,1,0, 1,0,1, 0,1,1, 0,0,1, 1,0.75,0};

void Game::initGame(void)
{
for (int i=0;i<NUM_OF_DIFFERENT_BRICKS;i++)
{ Btype[i].setup_areas(areas+32*i);
memcpy(Btype[i].colour,colours+i*3,sizeof(float)*3);
}

next_brick.rot = R0;
next_brick.pos.x = BOARDWIDTH/2;
next_brick.pos.y = BOARDHEIGHT;
next_brick.variety = brick_variety(rand()%NUM_OF_DIFFERENT_BRICKS);

addBrick();
score=0;
next_level(0);
}

void Game::next_level(int lvl)
{ level=lvl;
rows_left = level+3;
brick_falling_time = 800-level*80;
if (brick_falling_time < 25)
brick_falling_time=25;

for (int x=0;x<BOARDWIDTH;x++)
{ for (int y=0;y<BOARDHEIGHT;y++)
{ board[x][y].whats_here = NONE;
}
}

totalTime = glutGet(GLUT_ELAPSED_TIME);
srand(totalTime);
time_for_the_brick_to_fall = totalTime + brick_falling_time;

}

void Game::addBrick(void)
{
current_brick = next_brick;
next_brick.pos.x = BOARDWIDTH+6;
next_brick.pos.y = BOARDHEIGHT-8;

next_brick.rot = R0;
next_brick.variety = brick_variety(rand()%NUM_OF_DIFFERENT_BRICKS);
current_brick.pos.x = BOARDWIDTH/2;
current_brick.pos.y = BOARDHEIGHT;

if (!is_brick_able_to_be_here(current_brick))
gameover=true;
}

// tests to see if the brick ain't hitting the walls or another brick

bool Game::is_brick_able_to_be_here(brick b)
{ for (int i=0;i<4;i++)
{ int xx = Btype[b.variety].area[i][b.rot].x + b.pos.x;
int yy = Btype[b.variety].area[i][b.rot].y + b.pos.y;
if (xx<0 || xx>=BOARDWIDTH || yy<0 )
return false;

for (int x=0;x<BOARDWIDTH;x++)
{ for (int y=0;y<BOARDHEIGHT;y++)
{ if (board[x][y].whats_here && x==xx && y==yy)
return false;
}
}
}
return true;
}

// clean this up zed
int how_many_rows;

void Game::remove_rows(int startrow)
{
for (int j=startrow;j<BOARDHEIGHT;j++)
{ bool full=true;
for (int i=0;i<BOARDWIDTH;i++)
{ if (board[i][j].whats_here == NONE)
full=false;
}
if (full) // this row needs to be removed and all the others moved down
{ for (int jj=j;jj<BOARDHEIGHT-1;jj++)
{ for (int ii=0;ii<BOARDWIDTH;ii++)
{ board[ii][jj]=board[ii][jj+1];
}
}
how_many_rows++;
rows_left--;
if (rows_left<=0)
next_level(++level);
remove_rows(j);
}
}


}

void Game::add_brick_to_the_board(void)
{ int i;

brick b = current_brick;
for (i=0;i<4;i++)
{ int x = Btype[b.variety].area[i][b.rot].x + b.pos.x;
int y = Btype[b.variety].area[i][b.rot].y + b.pos.y;
board[x][y].whats_here = BLOCK;
memcpy(board[x][y].colour,Btype[b.variety].colour,sizeof(float)*3);

}
// see if we've completed a row
// should only check where we've put the last brick
score++; // 1 point per brick
how_many_rows=0;
remove_rows(0);

switch (how_many_rows)
{ case 0: break;
case 1: score+=25; break;
case 2: score+=100; break;
case 3: score+=250; break;
case 4: score+=500; break;
}
glColor4f(1,1,1,1);
char str[80];
glScissor(BRICKSIZE*BOARDWIDTH+32,BRICKSIZE*BOARDHEIGHT-64,320,96);
glClear( GL_COLOR_BUFFER_BIT);
glEnable(GL_BLEND); // any part of the texture black we won't draw
glBindTexture(GL_TEXTURE_2D, hud_Texture);
sprintf(str,"score %d",score);
drawText(str,BRICKSIZE*BOARDWIDTH+32,BRICKSIZE*BOARDHEIGHT,24);
sprintf(str,"rows left %d",rows_left);
drawText(str,BRICKSIZE*BOARDWIDTH+32,BRICKSIZE*BOARDHEIGHT-32,24);
sprintf(str,"level %d",level);
drawText(str,BRICKSIZE*BOARDWIDTH+32,BRICKSIZE*BOARDHEIGHT-64,24);
glDisable(GL_BLEND);

glBindTexture(GL_TEXTURE_2D, grafix_Texture);
glScissor(BRICKSIZE*BOARDWIDTH+128,BRICKSIZE*BOARDHEIGHT-196,BRICKSIZE*5,BRICKSIZE*4);
glClear( GL_COLOR_BUFFER_BIT);
addBrick();
drawBrick(next_brick);

glScissor(BRICKSIZE,BRICKSIZE,BRICKSIZE*BOARDWIDTH,BRICKSIZE*BOARDHEIGHT+BRICKSIZE*2);
}

void Game::drawBrick(brick b)
{ int x=b.pos.x;
int y=b.pos.y;

for (int i=0;i<4;i++)
{ int xx = Btype[b.variety].area[i][b.rot].x*BRICKSIZE;
int yy = Btype[b.variety].area[i][b.rot].y*BRICKSIZE;
glColor3fv(Btype[b.variety].colour);
drawSomeit((x+1)*BRICKSIZE + xx, (y+1)*BRICKSIZE + yy , 0, 0, 0.5, BRICKSIZE, BRICKSIZE);

}
}

// bollux function remove

void Game::moveBrick(int x,int y)
{ if (y)
{ current_brick.pos.y+=y;
}
if (x)
{ current_brick.pos.x+=x;
}
}


void Game::mainLoop(void)
{
// NOTE cause we are drawing everything 2d we don't need to clear the depth buffer cause there ain't one
glClear( GL_COLOR_BUFFER_BIT);

// we use this to keep the game running at the same speed on an athlon as a 486
float thisTick = glutGet(GLUT_ELAPSED_TIME);
currentTick = thisTick-lastTick;
totalTime+=currentTick;
lastTick = thisTick;

static int loopnum=0;
static float beginTick=thisTick;
loopnum++;
if (loopnum>=100)
{
fps = (1.0/((thisTick-beginTick)/loopnum))*1000.;
loopnum=0;
beginTick = thisTick;

char str[80];
sprintf(str,"Tetris %.d FPS",int(fps));
glutSetWindowTitle(str);
}

if (totalTime>time_for_the_brick_to_fall)
{ moveBrick(0,-1);
if (!is_brick_able_to_be_here(current_brick))
{ moveBrick(0,1); // move it back up
add_brick_to_the_board();

}
time_for_the_brick_to_fall = totalTime + brick_falling_time;
}

renderScreen();

}

#define BACKGROUNDSIZE 128

void Game::drawBackground(void)
{ glBindTexture(GL_TEXTURE_2D, grafix_Texture);
glColor3f(1,1,1);
for (int x=0;x<SCREENWIDTH;x+=BACKGROUNDSIZE)
{ for (int y=0;y<SCREENHEIGHT;y+=BACKGROUNDSIZE)
{
drawSomeit(x, y , 0.5, 0.0, 0.5, BACKGROUNDSIZE, BACKGROUNDSIZE);
}
}
}

static int first_time=0;

void Game::renderScreen(void)
{
glColor3f(1,1,1);
glBindTexture(GL_TEXTURE_2D, bottom_Texture);
// draw the background of eddie and richie twice
drawSomeit(BRICKSIZE, BRICKSIZE , 0, 0, 1, BRICKSIZE*BOARDWIDTH, BRICKSIZE*(BOARDHEIGHT+2)/2);
drawSomeit(BRICKSIZE, BRICKSIZE+BRICKSIZE*(BOARDHEIGHT+2)/2 , 0, 0, 1, BRICKSIZE*BOARDWIDTH, BRICKSIZE*(BOARDHEIGHT+2)/2);

glBindTexture(GL_TEXTURE_2D, grafix_Texture);
// draw all the bricks
for (int x=0;x<BOARDWIDTH;x++)
{ for (int y=0;y<BOARDHEIGHT;y++)
{ if (board[x][y].whats_here)
{ glColor3fv(board[x][y].colour);
drawSomeit((x+1)*BRICKSIZE, (y+1)*BRICKSIZE, 0, 0, 0.5, BRICKSIZE, BRICKSIZE);
}
}
}

// draw the players brick
drawBrick(current_brick);

// we're finished drawing int the back buffer so put the back buffer in the front buffer?
glutSwapBuffers();

}


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