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    • By jsquare89
      I am somewhat new to game development and trying to create a basic 3d engine. I have managed to set up a first person camera and it seems to be working fine for the most part. While I am able to look up, down, left and right just fine the camera is constrained to the mouse movement in the window (i.e when the mouse reaches edges of the window it discontinues camera rotation and mouse is out of window bounds. I tried to use SDL_WarpMouseInWindow(window, center.x,center.y) but when I do this then it messes up the camera and the camera is stuck, even though there is some slight movement of the camera, it keeps going back to the center.
      void Camera::UpdateViewByMouse(SDL_Window &window, glm::vec2 mousePosition)
      {
      float xDistanceFromWindowCenter = mousePosition.x - ((float)1024 / 2) ;
      float yDistanceFromWindowCenter = ((float)720 / 2) - mousePosition.y;
      yaw = xDistanceFromWindowCenter * cameraRotationSpeed;
      pitch = yDistanceFromWindowCenter * cameraRotationSpeed;
      SDL_WarpMouseInWindow(&window, 1024 / 2, 768 / 2); }
      i’ve been stuck on this for far too long. any help would be much appreciated
      i have also tried relative mouse movement,  and .xrel and .yrel to avail. polling mouse state with sdl_event. I do also know that SDL_WarpMouseInWindow makes change to event and have tried also ignore and reenabling to no avail
    • By smit patil
      I am at the first year of diploma and I am planing to make a nice small 2D or 3D First Person Shooter game . As I mentioned I am just at first year in IT ,I Dont know much about game developing but I do know lots of more things that normal 1st and even 3rd year students . 
      I  Know Java,C,C++ and little bit of python and GTK+ framework . I am currently trying to learn SDL and Qt with C++. I will also happily learn new technology if required to make games.
      Now my main Question's are:-
      How much time will it take to make SMALL 2D game as a single person in SDL while LEARNING SDL ?
      How much time will it take to make SMALL 3D game as a single person in SDL while LEARNING SDL ?
      Will learning Qt help me make games faster or with High performance ?
      My main platform is Linux and Android.I don't care if It runs on windows or Mac but it should run fine on Linux .
       
      Thanks in advance
       
       
    • By starfruit64
      Hello,
      I'm programming a simple rougelike video game for fun. I'm running into a very difficult problem with my room generation code, specifically the part that deals with the maze-like hallway to connect the randomly placed rooms inside a dungeon, using the depth-first search method. The code I've written is kinda long and probably hard to read, but I seriously cannot figure out what is causing the issue so try to bear with me please.
      Below is the header file for the Floor class, which generates the floor of the dungeon.
      #ifndef FLOOR_H_ #define FLOOR_H_ #include <iostream> #include <vector> #include <algorithm> #include "Cell.h" class Floor { private: int attempts; //Amount of attempts it tries to place a room before giving up. More attempts = more cramped. int maxdoor; //Maximum amount of doors on each room int maxroom; //Maximum number of rooms. 0 for 999. int maxheight, minheight; int maxwidth, minwidth; int maxbigroom; std::vector<std::vector<Cell> > region; //A collection of regions. A region is a collection of cells (rooms & hallway) std::vector<Cell> temp_region; //Used to fill the region. std::vector<Cell> temp_maze; std::vector<Cell> maze; public: Floor(); void init(int attempts, int maxdoor, int maxroom, int maxwidth, int minwidth, int maxheight, int minheight, int maxbigroom); void gen(Cell cell[120][60], SDL_Texture* tex); bool check_walls(Cell cell[120][60], int* x, int* y); }; #endif The main thing that is important in this header is the temp_maze vector, which is used to keep track of the current section of the maze that has been carved out, so that when the maze hits a dead end it can back track. is the Cell is a class that represents a cell in the 2D grid that the player can move on. For the issue of this post, just think of each Cell as having an X integer, a Y integer, and a Bool to keep track of whether or not the cell is opened up. 
      Below is the part of the gen function that deals with the hallway generation.
      //Hallway Generation int cur_x, cur_y; //Current cell being tested bool time_to_break; for (int i = 1; i < 119; i++) { for (int j = 1; j < 59; j++) { if (cell[i][j].return_blockade() == true && cell[i + 1][j].return_blockade() == true && cell[i][j + 1].return_blockade() == true && cell[i - 1][j].return_blockade() == true && cell[i][j - 1].return_blockade() == true) { //Start of a path cur_x = i; cur_y = j; while (true) { cell[cur_x][cur_y].set_bloc(false); //Opens up cell cell[cur_x][cur_y].set_tex(tex); cell[cur_x][cur_y].set_default_tex(tex); temp_maze.push_back(cell[cur_x][cur_y]); if (check_walls(cell, &cur_x, &cur_y) == false) { std::cout << "Entering nospace" << std::endl; std::cout << "Size of k: " << temp_maze.size() << std::endl; for (int k = temp_maze.size() - 1; k > -1; k--) { int xte = temp_maze[k].return_rect().x / 15; int yte = temp_maze[k].return_rect().y / 15; std::cout << "k: " << k << std::endl; std::cout << "rect_x: "<< temp_maze[k].return_rect().x<< " rect_y : "<< temp_maze[k].return_rect().y<< std::endl; std::cout << "x_te: " << xte << " y_te: " << yte << std::endl; if (check_walls(cell, &xte, &yte) == true) { cur_x = xte; cur_y = yte; std::cout << "Exiting nospace via newblock" << std::endl; break; } if (k == 0) { time_to_break = true; std::cout << "Exiting nospace via noviableblock" << std::endl; break; } } } if (time_to_break == true) { time_to_break = false; temp_maze.clear(); break; } } } } } The broad idea is that, starting from the top-left cell, we scroll through them until we find a cell that is not blocked, nor has any neighbors that are blocked. Than we open that cell up, add it to the temp_maze vector, and check whether it has any viable neighbors. If it does, it moves cur_y and cur_x to that new cell and repeats. If it doesn't have any viable neighbors, than it goes through the temp_maze vector until either it finds a cell that has viable neighbors, or it reaches the end of the vector. This is accomplished with the check_walls function.
      bool Floor::check_walls(Cell cell[120][60], int* x, int* y) { int ori_x = *x; int ori_y = *y; std::cout << "Entering checkwalls with x: " << ori_x << " y: " << ori_y << std::endl; if (cell[ori_x][ori_y].return_blockade() == true) { std::cout << "Checkwalls returns false due to being blocked" << std::endl; return false; } while (true) { *x = ori_x; *y = ori_y; bool upblock, rightblock, downblock, leftblock; int sidecount = 0; int dir = rand() % 4; if (dir == 0) { *y = (*y) - 1; } else if (dir == 1) { *x = (*x) - 1; } else if (dir == 2) { *y = (*y) + 1; } else if (dir == 3) { *x = (*x) + 1; } if (*x <= 0 || *y <= 0) { sidecount = 8; dir = 5; *x = ori_x; *y = ori_y; } if (cell[*x + 1][*y].return_blockade() == false) { sidecount++; } if (cell[*x - 1][*y].return_blockade() == false) { sidecount++; } if (cell[*x][*y + 1].return_blockade() == false) { sidecount++; } if (cell[*x][*y - 1].return_blockade() == false) { sidecount++; } if (sidecount <= 1) { std::cout << "Checkwalls returns true" << std::endl; return true; } else { if (dir == 0) { upblock = true; } else if (dir == 1) { leftblock = true; } else if (dir == 2) { downblock = true; } else if (dir == 3) { rightblock = true; } } if (upblock == true && leftblock == true && downblock == true && rightblock == true) { *x = ori_x; *y = ori_y; std::cout << "Checkwalls returns false" << std::endl; return false; } } } The basic idea here is that if one of the neighbors are available, than it moves x & y to that cell and return true, and if there are none, than return false.
       
      The problem is that when I run this the temp_maze  function seems to get filled with the same cell, and time_to_break never gets set to true, as the vector seems to never end. Once again I understand this is kind of a lot but I have looked at this for a couple days now and have no idea what i am doing wrong, so any help would be very much appreciated.
    • By reenigne
      For those that don't know me. I am the individual who's two videos are listed here under setup for https://wiki.libsdl.org/Tutorials
      I also run grhmedia.com where I host the projects and code for the tutorials I have online.
      Recently, I received a notice from youtube they will be implementing their new policy in protecting video content as of which I won't be monetized till I meat there required number of viewers and views each month.

      Frankly, I'm pretty sick of youtube. I put up a video and someone else learns from it and puts up another video and because of the way youtube does their placement they end up with more views.
      Even guys that clearly post false information such as one individual who said GLEW 2.0 was broken because he didn't know how to compile it. He in short didn't know how to modify the script he used because he didn't understand make files and how the requirements of the compiler and library changes needed some different flags.

      At the end of the month when they implement this I will take down the content and host on my own server purely and it will be a paid system and or patreon. 

      I get my videos may be a bit dry, I generally figure people are there to learn how to do something and I rather not waste their time. 
      I used to also help people for free even those coming from the other videos. That won't be the case any more. I used to just take anyone emails and work with them my email is posted on the site.

      I don't expect to get the required number of subscribers in that time or increased views. Even if I did well it wouldn't take care of each reoccurring month.
      I figure this is simpler and I don't plan on putting some sort of exorbitant fee for a monthly subscription or the like.
      I was thinking on the lines of a few dollars 1,2, and 3 and the larger subscription gets you assistance with the content in the tutorials if needed that month.
      Maybe another fee if it is related but not directly in the content. 
      The fees would serve to cut down on the number of people who ask for help and maybe encourage some of the people to actually pay attention to what is said rather than do their own thing. That actually turns out to be 90% of the issues. I spent 6 hours helping one individual last week I must have asked him 20 times did you do exactly like I said in the video even pointed directly to the section. When he finally sent me a copy of the what he entered I knew then and there he had not. I circled it and I pointed out that wasn't what I said to do in the video. I didn't tell him what was wrong and how I knew that way he would go back and actually follow what it said to do. He then reported it worked. Yea, no kidding following directions works. But hey isn't alone and well its part of the learning process.

      So the point of this isn't to be a gripe session. I'm just looking for a bit of feed back. Do you think the fees are unreasonable?
      Should I keep the youtube channel and do just the fees with patreon or do you think locking the content to my site and require a subscription is an idea.

      I'm just looking at the fact it is unrealistic to think youtube/google will actually get stuff right or that youtube viewers will actually bother to start looking for more accurate videos. 
    • By Jeff de Anda
      Question about SDL_Rect scope.
      Say I have a member function like so.
      void drawRect(int x, int y, int w, int y) { SDL_Rect r = {x, y, w, h}; SDL_RenderDrawRect(m_renderer, &r); } Will it cause problems if SDL_Rect goes out of scope before calling SDL_RenderPresent?
      I cannot tell if the values are copied from SDL_Rect when calling SDL_RenderDrawRect or if internally SDL is storing the pointer until SDL_RenderPresent is called.
      Thanks!
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SDL SDL Functions failing and causing segfaults, and I don't know why

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I am attempting to make a Pong game using SDL. I'm trying to render text on the screen, but segfaults prevent the code from running. I ran it in gdb, and found that the segfaults occur because SDL_QueryTexture doesn't give the ints passed into it any values. I put a statement to print SDL_GetError() after SDL_QueryTexture, and it says: "Failed loading SHCORE.DLL: The specified module could not be found." This wasn't happening after I made some adjustments to my code, so I believe the code is causing this problem. The relevant code is below:

 

In case the rest of the code has a part in this, the entire .cpp file is attached.

	void loadText(string s) {
            SDL_Color color = {255,255,255};
            SDL_Surface* textsurface = TTF_RenderText_Solid(font, s.c_str(), color);
            if(textsurface == NULL) {
                cout << "Could not rendertext onto surface" << endl;
            }
            texture = SDL_CreateTextureFromSurface(r,textsurface);
            if(texture == NULL) {
                cout << "Could not make texture" << SDL_GetError() << endl;
            }
            SDL_QueryTexture(texture, NULL, NULL, w, h);
            cout << SDL_GetError() << endl;
            SDL_FreeSurface(textsurface);
            textsurface = NULL;
            
                //cout << "Texture query error" << SDL_GetError() << endl;
            
        }
	void textRender(int x, int y) {
            
            destinationrect = {x,y,*w,*h};
            if (SDL_RenderCopy(r,texture,NULL,&destinationrect) < 0) {
                cout << "Rendercopy error" << SDL_GetError() << endl;
            }
            
            
        }
	 
	

test.cpp

OpenSans-Regular.ttf

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I doubt the error message is coming from SDL_QueryTexture (it shouldn't be attempting to load any DLLs). I see two problems with your code that you need to correct before reaching that conclusion.

First, you aren't checking the return value of the function call. The function is documented to return zero on success and a negative error code on failure.

Second, based on your usage of w and h in textRender, it seems you've declared both as pointers. This is likely the source of your segfault. SDL_QueryTexture does not store pointers to ints in the width and height parameters. It stores the actual values of the width and height. That means you have to pass it the addresses of actual int variables, not uninitialized int pointers. In other words:

// This is certain to cause a segault
int *w, *h;
SDL_QueryTexture(tex, NULL, NULL, w, h);

The correct way to do this is like so:

int w = 0, h = 0;
if(SDL_QueryTexture(tex, NULL, NULL, &w, &h) < 0)  {
  fprintf(stderr, "Error on texture query: %s", SDL_GetError());
}

 

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