I am still learning SFML and C++ so please understand that I'm still at the basic level.
This is my first time using this site so IDK if I'm doing this right.
I want to make a function, set, that will allow me to pass a 2d array as an argument and place a tile down whenever there is a 1 in the array. So I can draw maps and things using a matrix. ww is the window width and wh is the window height. In main I made a for loop that would go through tiles and draw them to the window. But when I run this it gives me the error: Segmentation Fault (core dumped) "Error: 139". Is there a better way of doing this and what am I doing wrong?
Thank you.
struct field
{
int rectsizex;
int rectsizey;
RectangleShape * tiles;
field (int s)
{
rectsizex = ww / s;
rectsizey = wh / s;
tiles = new RectangleShape[rectsizex * rectsizey];
}
~field()
{
delete tiles;
}
RectangleShape * set(int ** matr)
{
Vector2f size((ww / rectsizex), (wh / rectsizey));
int posx = ww / rectsizex;
int posy = wh / rectsizey;
for(int x = 0; x<rectsizex; x++)
{
for(int y = 0; y<rectsizey; y++)
{
int i = ((x*rectsizey)+1)+y;
tiles[i].setSize(size);
if(matr[x][y] == 1)
{
tiles[i].setFillColor(Color::Black);
}
else
{
tiles[i].setFillColor(Color::White);
}
tiles[i].setPosition(x * posx, y * posy);
}
}
return tiles;
}
};
Find out what values you are getting for i:
int i = ((x*rectsizey)+1)+y;
This value is definitely outside of your array bounds, hence the error. Use a debugger, or put some print statements after you get the i value.
Related
I am learning C++ and want to get into graphics. I am using SFML, and am trying to make a snake game. I want to use rectangle shapes and update the position of each rectangle by referring to an array and factor of 40 (my tilesize). I believe I got the for loops right, but am struggling to use sf::setPosition. It gives me a conversion error. Here is my code:
#include <SFML\Graphics.hpp>
int main()
{
int xWindow = 1280; //Divided by 40 pixels, equals to a width of 32 tiles
int yWindow = 720; //Divided by 40 pixels, equals to a height of 18 tiles
float array[32][18] = { 0 };
sf::RenderWindow window(sf::VideoMode(xWindow, yWindow), "Title"); //32 & 18
while (window.isOpen())
{
////////Grid variables/////////
int xFactor = 32;
int yFactor = 18;
int size = 40;
////////Events////////
////////draw////////
window.clear();
for (int i = 0; i <= 31;i++)
{
for (int j = 0; j <= 17; j++)
{
sf::RectangleShape block(sf::Vector2f(size, size));
block.setFillColor(sf::Color::Blue);
block.setPosition(array[i * size][j * (size)]); //ERROR OCCURS HERE: cannot convert argument 1 from 'float' to 'const sf::Vector2f &'
window.draw(block);
}
}
///////Display//////
window.display();
}
}
I am thinking that setPosition only takes float or vector as input, but if I'm not mistaken you can't move through an array with anything other than integers?
How would set up a simple grid like this in SFML C++?
Thanks for any answers!
A position is 2 numbers, an x and y cordinate. array[i * size][j * (size)] is just one number in your 2d float array.
I would go for something like this instead
block.setPosition(i*size, j*size);
I am trying to develop a c++ program with opencv library on Xcode 9.3, macOS 10.14, using clang. During weeks I've been trying to solve or understand why I am getting an undefined behavior error that sometimes makes my program crash and sometimes not.
I am reading a set of images from different cameras and storing them in a multidimensional array: silC[camera][image]. (images are well stored)
I get this error THREAD 1: EXC_BAD_ACCESS (code=1, address=0x1177c1530) when I do this: currentImage.at(x,y) even the values of currentImage are not the problem nor the image.
I post the code below if there's any chance someone could help me..
vector< vector<Mat> > silC(8,vector<Mat>()); // Store the pbm images separating from different cameras
* I read the images and store them in silC. *
for (int z=0; z < nz; z++) {
for (int y=0; y < ny; y++) {
for (int x=0; x < nx; x++) {
// Current voxel coordinates in the 3D space
float xcoord = x*voxelsize + Ox + voxelsize/2;
float ycoord = y*voxelsize + Oy + voxelsize/2;
float zcoord = z*voxelsize + Oz + voxelsize/2;
for (int camId=0; camId < matricesP.size(); camId++) {
imgId = 0;
currentImage = silC[camId][imgId];
int w = silC[camId][imgId].cols;
int h = silC[camId][imgId].rows;
// Project the voxel from the 3D space to the images
Mat P = matricesP[camId];
Mat projection = P*(Mat_<float>(4,1) << xcoord,ycoord,zcoord,1.0);
//We get the point in homog coord.
float xp = projection.at<float>(0);
float yp = projection.at<float>(1);
float zp = projection.at<float>(2);
// Get the cartesian coord
int xp2d = cvRound(xp/zp);
int yp2d = cvRound(yp/zp);
if(xp2d >= 0 && xp2d < w && yp2d >= 0 && yp2d < h){
// all values are correct! :/
// int value = silC[camId][imgId].at<float>(xp2d, yp2d); // undefined behaviour: crashes sometimes..
int value = currentImage.at<float>(xp2d, yp2d); // undefined behaviour also crashes sometimes..
if(value == 255){
cout << "Voxel okey \n";
}
}
}
}
}
}
EDIT:
The solution posted on comments below is that instead of currentImage.at(xp2d,yp2d) --> currentImage.at(yp2d,xp2d), as cv::Mat access requieres.
BUT, I tried to parallelize the for several times with openMP (#pragma omp parallel for) but it kept crashing. If someone is familiar with parallelize I'll appreciate any help.
the solution is what #rafix07 posted. Thank you very much guys, next time I'll try to focus more.
I am having some problems related to using boost::gil library when I try to resize an image view. I would like to access the pixels content of a image view after resizing it. However, I always obtain a segmentation fault when doing this.
Here is my code:
boost::gil::rgb8_image_t rgb_image;
//Try to convert image file to raw binary data
try {
boost::gil::read_and_convert_image("/tmp/image.jpg", rgb_image, boost::gil::jpeg_tag());
} catch (...) {
return;
}
boost::gil::rgb8_view_t rgb_view;
boost::gil::rgb8_image_t rgb_image_resize(150, 200);
boost::gil::resize_view(boost::gil::const_view(rgb_image), boost::gil::view(rgb_image_resize), boost::gil::bilinear_sampler());
rgb_view = boost::gil::view(rgb_image_resize);
for (std::uint32_t i = 0; i < 150; i++) {
boost::gil::rgb8_view_t::x_iterator it_image = rgb_view.row_begin(i);
for (size_t width = 0; width < 200; width++) {
if (it_image->at_c_dynamic(0) * 0.299 + it_image->at_c_dynamic(1) * 0.114 + it_image->at_c_dynamic(2) * 0.587 < 80) {//color filter. Trying to execute this line gives me a seg fault
//do something
} else { //white pixel
//do something
}
it_image++;
}
}
Could you please indicate me what is my problem? If I delete the resize_view function and create the view directly from the rgb_image, it works perfectly.
The line rgb_view.row_begin(i); gives you X-navigation iterator of i-th row which you can use to iterate over the i-th row pixels.
But, you increment this iterator it_image++; in the nested loop, that is 150 * 200 times, what makes it go far beyond the end of the last pixel of the i-th row.
Here is example that shows one of possible ways to achieve the correct iteration:
#include <boost/gil.hpp>
#include <boost/gil/extension/io/jpeg.hpp>
#include <boost/gil/extension/numeric/resample.hpp>
#include <boost/gil/extension/numeric/sampler.hpp>
int main()
{
namespace bg = boost::gil;
bg::rgb8_image_t rgb_image;
bg::read_and_convert_image("/tmp/example/test.jpg", rgb_image, bg::jpeg_tag());
bg::rgb8_image_t rgb_image_resize(68, 49); // rgb_image is 136x98
bg::resize_view(bg::const_view(rgb_image), bg::view(rgb_image_resize), bg::bilinear_sampler());
auto rgb_view = bg::view(rgb_image_resize);
for (int y = 0; y < rgb_view.height(); ++y)
{
bg::rgb8_view_t::x_iterator it_row = rgb_view.row_begin(y);
for (int x = 0; x < rgb_view.width(); ++x)
{
auto p = it_row[x];
if (p.at_c_dynamic(0) * 0.299 + p.at_c_dynamic(1) * 0.114 + p.at_c_dynamic(2) * 0.587 < 80)
; //do something
else
; //do something
}
}
}
For more options, check the Boost.GIL tutorial with example computing the image gradient.
NOTE: The I/O extensions have been entirely rewritten in Boost.GIL released in Boost 1.68. The example above is based on GIL from Boost 1.68.
So I'm trying to modify the Kinect BodyBasicsD2D code so that a fixed number of "target positions" appear on the screen (as ellipses) for the user to move his hand toward. I'm having trouble creating the initial target positions.
This is my code in the header file for the allocation of the array of target positions (these are a public field of the CBodyBasics class, already built into the original BodyToBasics program):
D2D1_POINT_2F* targetPositions = NULL;
int numTargets = 3;
Then I have a function "GenerateTargetPositions" which is supposed to generate 3, in this case, target positions to be passed into the "DrawTargetPositions" function.
void CBodyBasics::GenerateTargetPositions(D2D1_POINT_2F * targetPositions, int numTargets)
{
targetPositions = new D2D1_POINT_2F[numTargets];
RECT rct;
GetClientRect(GetDlgItem(m_hWnd, IDC_VIDEOVIEW), &rct);
int width = rct.right;
int height = rct.bottom;
FLOAT x;
FLOAT y;
D2D1_POINT_2F tempPoint;
for (int i = 0; i < numTargets; i++) {
x = 1.0f*i*width / numTargets;
y = 1.0f*i*height / numTargets;
tempPoint = D2D1::Point2F(x, y);
targetPositions[i] = tempPoint;
}
}
My DrawTargetPositions function is:
void CBodyBasics::DrawTargetPositions(D2D1_POINT_2F * targetPositions, int numTargets)
{
D2D1_ELLIPSE ellipse;
for (int i = 0; i < numTargets; i++)
{
ellipse = D2D1::Ellipse(targetPositions[i], 50.f, 50.f);
m_pRenderTarget->FillEllipse(ellipse, m_pSilverBrush);
}
}
When I try to run my code, I get the error that both "targetPositions" and "targetPositions[i]" is NULL (and thus my GenerateTargetPositions function must not be working properly). I believe that targetPositions[i] is a struct (a point with x and y values) so I am wondering if this may be the reason for my errors.
I call GenerateTargetPositions and DrawTargetPositions before the main "while" loop in my code so that each function is not being called on each iteration (there are many iterations of through the while loop because this is an interactive Microsoft Kinect, recording one's movements).
Any suggestions and advice would be greatly appreciated. Thanks so much!
{Hopefully improved my post, please still suggest any other code you need, and once again im sorry for being so clueless, im determined to get past this problem though so i truly appreciate your time!!!}
**EDIT: thanks to Frank with his reply below, the program now starts and draws the three enemies, but just a few second later crashes, the program code below therefore is still applicable as its basically the move loop and somewhere in there something is still going wrong.
I realise this is extremely obscure and i have tried my best to explain it, but if noone can advise then the few second its up should be enough to complete the tutorial anyway and ill dissect the whole project after its finished and really try and break it down and learn as much as possible.**
Okay, so I run this loop designed to create new enemies, and then draw them onto the screen, it now works, but after a few second crashes. below is the steps the debugging goes through and the call stack at the end if what it displayed after the crash. hope you can help!
this is a video tutorial im following and im stuck, cant find the answer. checked the code over and over again. (the full code is at the bottom of the post (codeblocks,) but i have tried to include as much info as possible in this post)
the function is:
level->addEnemies(3);
which looks like in the main game.cpp:
bool Game::run(void)
{
level = new Level(&drawArea, 30, 20);
drawArea.createBackgroundTile(TILE_EMPTY, ' ');
drawArea.createBackgroundTile(TILE_WALL, 219);
drawArea.createSprite(SPRITE_PLAYER, 1);
drawArea.createSprite(SPRITE_ENEMY, '$');
player = new Character(level, &drawArea, 0);
level->draw();
level->addPlayer(player);
level->addEnemies(3); <-------- SKIPS TO THIS FUNC
char key = ' ';
startTime = timeGetTime();
frameCount = 0;
lastTime = 0;
posx = 0;
player->move(0,0);
while (key != 'q')
{
while (!getInput(&key))
{
timerUpdate();
}
level->keyPress(key);
}
delete player;
return true;
}
the function in full is below, note that when i remove this addEnemies function from the main game loop everything runs perfectly fine with no crash, so it has something to do with the upcoming functions.
void Level::addEnemies(int num)
{
int i = num;
while (i > 0)
{
int xpos = int(float(rand() % 100) / 100) * (width - 2) + 1;
int ypos = int(float(rand() % 100) / 100) * (height - 2) + 1;
if (level[xpos][ypos] != TILE_WALL)
{
Enemy *temp = new Enemy(this, drawArea, SPRITE_ENEMY,
(float)xpos, float(ypos));
temp->addGoal(player);
addNPC((Sprite *)temp);
i--;
}
}
}
It gets through this function without any problems it seems.
After this function is goes back to the game loops and executes through fine, goes into timer update without any problems. Here is the timerUpdate function:
void Game::timerUpdate(void)
{
double currentTime = timeGetTime() - lastTime;
if (currentTime < GAME_SPEED)
return;
level->update(); <--------SKIPS TO THIS FUNC
frameCount++;
lastTime = timeGetTime();
}
This is the Level->Update() Func:
void Level::update(void)
{
for (Iter = npc.begin(); Iter != npc.end(); Iter++)
{
(*Iter)->idleUpdate(); <-------------SKIPS TO THIS FUNC
if ((*Iter)->isAlive() == false)
{
Sprite *temp = *Iter;
//kill the enemy
Iter--;
delete temp;
npc.remove(temp);
}
}
}
idleUpdate():
void Enemy::idleUpdate(void)
{
if (goal)
simulateAI(); <------ Goes to this func
}
simulateAI():
void Enemy::simulateAI(void)
{
vector goal_pos = goal->getPosition();
vector direction;
direction.x = goal_pos.x - pos.x;
direction.y = goal_pos.y - pos.y;
float mag = sqrt(direction.x * direction.x + direction.y * direction.y);
direction.x = direction.x / (mag);
direction.y = direction.y / (mag);
if (!move(direction.x, direction.y)) <------ SKIPS TO THIS FUNC
{
while (!move(rand() % 3 - 1, rand() % 3 - 1))
{
}
}
move function:
bool Sprite::move(float x, float y)
{
int xpos = (int)(pos.x +x);
int ypos = (int)(pos.y +y);
if (isValidLevelMove(xpos,ypos)) SKIPS TO THIS FUNC
{
//.....rest not needed
isValidMove func:
bool Sprite::isValidLevelMove(int xpos, int ypos)
{
if (level->level[xpos][ypos] != TILE_WALL) <-------------THIS LINE CRASHES!!
return true;
return false;
}
I really cant figure out where this goes wrong, and why at the end the call stakc shows such high out of bounds numbers for xpos adn ypos.
Here is the full call stack:
#0 00402920 Sprite::isValidLevelMove (this=0x791498, xpos=-2147483648, ypos=-2147483648) (sprite.cpp:95)
#1 00000000 0x00401750 in Enemy::move (this=0x791498, x=-nan(0x400000) (enemy.cpp:21)
#2 00401892 Enemy::simulateAI (this=0x791498) (enemy.cpp:67)
#3 004017E5 Enemy::idleUpdate (this=0x791498) (enemy.cpp:46)
#4 0040226E Level::update (this=0x792e90) (level.cpp:86)
#5 00401CB8 Game::timerUpdate (this=0x28fec0) (game.cpp:93)
#6 00401BB5 Game::run (this=0x28fec0) (game.cpp:54)
#7 0040258D main() (main.cpp:11)
which basically tells me xpos and ypos have been mutilated from somehere in thsi proccess and thats causeing the crash im sure because its way out of bounds from the [30][20] int array of the width and height of the drawengine.
ANOTHER EDIT:
Here is the Sprite class, if it helps, will edit in more if needed.
enum
{
SPRITE_CLASSID,
CHARACTER_CLASSID,
ENEMY_CLASSID
};
struct vector
{
float x;
float y;
};
class Sprite
{
public:
Sprite(Level *l, DrawEngine *de, int s_index, float x = 1, float y = 1, int i_lives = 1);
~Sprite();
vector getPosition(void);
float getX(void);
float getY(void);
virtual void addLives(int num = 1);
int getLives(void);
bool isAlive(void);
virtual void idleUpdate(void);
virtual bool move(float x, float y);
protected:
Level *level;
DrawEngine *drawArea;
vector pos;
int spriteIndex;
int numLives;
int classID;
vector facingDirection;
void draw(float x, float y);
void erase(float x, float y);
bool isValidLevelMove(int xpos, int ypos);
};
anyway any help and i would be sooooo grateful, i know i must seem totally useless, but i rteally am determined to learn, and any help you guys can provide would be priceless!!!!
full code file (codeblocks) : http://www.mediafire.com/?5xz2seadmagbetb
This might not be the actual problem, but could be related. Your code to create a random position within your Level::addEnemies(int num) function will always return 1 for xpos and ypos.
This is because of the way you apply the casts. You seem to miss parenthesis for your final cast to int. I think you want something like this:
int xpos = int((float(rand() % 100) / 100) * (width - 2)) + 1;
Update:
The code causing the crash is located in your simulateAI() function. With:
float mag = sqrt(direction.x * direction.x + direction.y * direction.y);
You calculate the distance between two points, but if the points have the same coordinates, the distance is 0.
Later with: direction.x = direction.x / (mag); you devide by this potential 0 and as a result your coordinates will contain NaN. Within your bool Sprite::move(float x, float y) function you cast these NaNs into an int which will give you some undefined number. With this number you are trying to access your array which will lead to the access violation that crashes your program.
So first thing to do is to check for a zero distance and handle that differently.