I'm trying to open a window with SDL2 in visual studio 2015. I've set a .bmp image in my code to display to the screen in a window, but when I run my code the program returns 0 and closes without a window. The .bmp image is in the project folder. How do you display the window?
#include <SDL.h>
#include <iostream>
int main(int argc, char* args[])
{
SDL_Window *window = nullptr;
SDL_Surface *windowSurface = nullptr;
SDL_Surface *imageSurface = nullptr;
if (SDL_Init(SDL_INIT_VIDEO) < 0)
std::cout << "Game Initialization error: " << SDL_GetError() << std::endl;
{
window = SDL_CreateWindow("Contrast Beta 0.0.1", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 920, SDL_WINDOW_HIDDEN | SDL_WINDOW_FULLSCREEN);
if (window == NULL)
std::cout << "Window Creation Failed, Error: " << SDL_GetError() << std::endl;
else
{
//Window Created
windowSurface = SDL_GetWindowSurface(window);
imageSurface = SDL_LoadBMP("Background.bmp");
if (imageSurface == NULL)
std::cout << "Error loading background: " << SDL_GetError() << std::endl;
else
{
SDL_BlitSurface(imageSurface, NULL, windowSurface, NULL);
SDL_UpdateWindowSurface(window);
SDL_Delay(2000);
}
}
}
SDL_DestroyWindow(window);
SDL_Quit();
return 0;
}
Remove SDL_WINDOW_HIDDEN; that's all.
Related
I am doing a game using SDL.
The problem is that instead of getting image I see a black screen without any errors. And the most interesting thing that I've made another test project to see if I'll get an image and this one works excellent. In test project I have only main.cpp which does the same (not sure as i am getting black screen in my main project) and not using headers and this stuff.
Here is my code:
main.cpp(game project)
#include <SDL2\SDL.h>
#include <SDL2\SDL_image.h>
#include <iostream>
#include <stdio.h>
#include "RenderWindow.hpp"
int main(int argc, char** argv){
if (SDL_Init(SDL_INIT_VIDEO) > 0)
std::cout << "SDL_init has crushed" << SDL_GetError() << std::endl; // ініціалізація сдл
if (!(IMG_Init(IMG_INIT_PNG)))
std::cout << "IMG_init has failed. Error: " << IMG_GetError() << std::endl;
RenderWindow window("Game",640,480);
SDL_Texture* grassTexture = window.loadTexture("images/ground_grass_1.png");
bool gameRunning = true;
SDL_Event event;
while(gameRunning)
{
while(SDL_PollEvent(&event))
{
if(event.type == SDL_QUIT)
gameRunning = false;
}
window.clear();
window.render(grassTexture);
window.display();
}
window.cleanUp();
IMG_Quit();
SDL_Quit();
return 0;
}
RenderWindow.hpp
#pragma once
#include <SDL2\SDL.h>
#include <SDL2\SDL_image.h>
class RenderWindow
{
public:
RenderWindow(const char* p_title, int p_w, int p_h);
SDL_Texture* loadTexture(const char* p_filePath);
void cleanUp();
void clear();
void render(SDL_Texture* p_text);
void display();
private:
SDL_Window* window;
SDL_Renderer* renderer;
};
renderwindow.cpp
#include <SDL2\SDL.h>
#include <SDL2\SDL_image.h>
#include <iostream>
#include "RenderWindow.hpp"
RenderWindow::RenderWindow(const char* p_title, int p_w, int p_h)
:window(NULL), renderer(NULL) // присвоювання нульових поінтеров
{
window = SDL_CreateWindow(p_title,SDL_WINDOWPOS_UNDEFINED,SDL_WINDOWPOS_UNDEFINED,p_w,p_h,SDL_WINDOW_SHOWN); // ініціалізація вікна
if(window == NULL)
std::cout << "Window failed to init" << SDL_GetError() << std::endl;
renderer = SDL_CreateRenderer(window,-1,SDL_RENDERER_ACCELERATED); // ініціалізація рендера
if(renderer == NULL)
std::cout << "Renderer failed to init" << SDL_GetError() << std::endl;
}
SDL_Texture* RenderWindow::loadTexture(const char* p_filePath)
{
SDL_Texture* texture = NULL;
texture = IMG_LoadTexture(renderer,p_filePath);
if(texture = NULL)
std::cout << "Failed to load texture. Error: " << SDL_GetError() << std::endl;
return texture;
}
void RenderWindow::cleanUp()
{
SDL_DestroyWindow(window);
}
void RenderWindow::clear()
{
SDL_RenderClear(renderer);
}
void RenderWindow::render(SDL_Texture* p_tex)
{
SDL_RenderCopy(renderer,p_tex,NULL,NULL);
}
void RenderWindow::display()
{
SDL_RenderPresent(renderer);
}
and main.cpp(test project)
#include <SDL2/SDL.h> // include the SDL library
#include <SDL2/SDL_image.h> // include the SDL_image library for loading image files
#include <iostream>
int main(int argc, char* argv[]) {
// initialize SDL
if (SDL_Init(SDL_INIT_VIDEO) < 0) {
std::cout << "SDL initialization failed: " << SDL_GetError() << std::endl;
return 1;
}
// create the window
SDL_Window* window = SDL_CreateWindow("My Window", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 640, 480, SDL_WINDOW_SHOWN);
if (window == NULL) {
std::cout << "Failed to create window: " << SDL_GetError() << std::endl;
return 1;
}
// create the renderer
SDL_Renderer* renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
if (renderer == NULL) {
std::cout << "Failed to create renderer: " << SDL_GetError() << std::endl;
return 1;
}
// load the image file
SDL_Texture* texture = IMG_LoadTexture(renderer, "ground_grass_1.png");
if (texture == NULL) {
std::cout << "Failed to load image: " << SDL_GetError() << std::endl;
return 1;
}
// render the image
SDL_RenderCopy(renderer, texture, NULL, NULL);
SDL_RenderPresent(renderer);
// wait for 5 seconds
SDL_Delay(5000);
// clean up
SDL_DestroyTexture(texture);
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();
return 0;
}
I'm trying to get an SDL window to appear, but it doesn't seem to be working. The program will run, and the function to show the window will run with no errors, but nothing shows up on my screen. I only have an icon in the dock that says that the program is not responding. Here's my code:
int main(int argc, const char * argv[]) {
MainComponent mainComponent;
mainComponent.init();
char myVar;
cout << "Enter any key to quit...";
cin >> myVar;
return 0;
}
void MainComponent::init() {
//Initialize SDL
SDL_Init(SDL_INIT_EVERYTHING);
window = SDL_CreateWindow("My Game Window", 100, 100, 100, 100, SDL_WINDOW_SHOWN);
cout << screenWidth << " " << screenHeight << endl;
if(window == nullptr) {
cout << "Error could not create window" << SDL_GetError() << endl;
}
SDL_Delay(5000);
}
Here's a screenshot of the icon on the dock https://www.dropbox.com/s/vc01iqp0z07zs25/Screenshot%202016-02-02%2017.26.44.png?dl=0
Let me know if there's something I'm doing wrong, thanks!
SDL_Renderer should be initialized to handle the rendering. This is explained in detailed here What is a SDL renderer?.
Here's a modified code above with an initialized renderer;
#include <SDL2/SDL.h>
#include <iostream>
using namespace std;
class MainComponent
{
public:
void init();
~MainComponent();
private:
SDL_Window *window;
SDL_Renderer* renderer;
};
MainComponent::~MainComponent()
{
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
}
void MainComponent::init() {
//Initialize SDL
SDL_Init(SDL_INIT_EVERYTHING);
int screenWidth = 400;
int screenHeight = 300;
window = SDL_CreateWindow("My Game Window", 100, 100, screenWidth, screenHeight, SDL_WINDOW_SHOWN);
renderer = SDL_CreateRenderer(window, -1, 0);
cout << screenWidth << " " << screenHeight << endl;
if(window == nullptr) {
cout << "Error could not create window" << SDL_GetError() << endl;
}
//change the background color
SDL_SetRenderDrawColor(renderer, 255, 0, 0, 255);
// Clear the entire screen to our selected color.
SDL_RenderClear(renderer);
// Up until now everything was drawn behind the scenes.
// This will show the new, red contents of the window.
SDL_RenderPresent(renderer);
SDL_Delay(5000);
}
int main(int argc, const char * argv[]) {
MainComponent mainComponent;
mainComponent.init();
char myVar;
cout << "Enter any key to quit...";
cin >> myVar;
SDL_Quit();
return 0;
}
This should compile and run properly.
Hope that helps.
Stack Trace :
So, I'm trying to create a 2D game and right now I'm trying to display and move a image, however when I Debug the game/run it, visual studio and the game freezes and can't quit, not even when using the task manager to kill it.
The only way to unfreeze it is by logging off or restarting the pc which forces both of them to close.
I also get some weird error :
Unhandled exception at 0x71002A95 (SDL2_ttf.dll) in SDLGame.exe: 0xC0000005: Access violation reading location 0x00000000.
I have no idea what it means and how to fix it, but I'm guessing it has something to do with my code that I need to change.
Here's my code :
#include <iostream>
#include <SDL.h>
#include <SDL_image.h>
#include <SDL_ttf.h>
// Macros
#define pause system("PAUSE"); // Works on windows only, removed in alpha / beta versions.
// Pre "init" of functions
void QuitGame();
int InitGame();
void processInput();
void InitRects();
// Variables
int FramesPassed = 0;
int FramesPerSecond = 0; // Not used yet
SDL_Renderer* renderer = nullptr;
SDL_Window* window = nullptr;
SDL_Event evnt;
SDL_Rect sprite1_Rect;
SDL_Rect FPS_Text_Rect;
TTF_Font* Sans = TTF_OpenFont("Fonts/Aaargh.ttf", 40);
SDL_Color Color_White = { 255, 255, 255 };
SDL_Surface* FPS_Text_Surface = nullptr;
SDL_Texture* FPS_Text = nullptr;
SDL_Texture* testImg = nullptr;
static bool isRunning = true;
int SDL_main(int argc, char* argv[])
{
InitGame();
InitRects();
std::cout << "Displaying text on screen using SDL TTF doesn't work" << std::endl;
std::cout << "This happens when the TTF Surface is being rendered on screen" << std::endl;
std::cout << "check line : 123 and 124." << std::endl;
while (isRunning)
{
FramesPassed++;
processInput();
SDL_RenderClear(renderer); // Clears the last/current frame?
// Render testImage on screen. (needs to be between render present and clear.)
SDL_RenderCopy(renderer, testImg, NULL, &sprite1_Rect);
SDL_RenderCopy(renderer, FPS_Text, NULL, &FPS_Text_Rect);
SDL_RenderPresent(renderer); // Pretty much draws everything again.
}
return 0;
QuitGame();
}
int InitGame()
{
std::cout << "Game Initializing..." << std::endl;
std::cout << "TTF SDL Initializing..." << std::endl;
if (TTF_Init() < 0)
{
std::cout << "SDL TTF Failed To Initialize : " << TTF_GetError() << std::endl;
pause
QuitGame();
}
else
{
std::cout << "SDL TTF Initialized Successfully" << std::endl;
if (SDL_Init(SDL_INIT_EVERYTHING) < 0)
{
std::cout << "SDL Initialization Failed : " << SDL_GetError() << std::endl;
pause
QuitGame();
}
else
{
std::cout << "SDL Initializing" << std::endl;
window = SDL_CreateWindow("Game Title", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1024, 720, SDL_WINDOW_SHOWN);
if (window == NULL)
{
std::cout << "Window Creation Failed : " << SDL_GetError() << std::endl;
pause
QuitGame();
}
else
{
std::cout << "SDL Initialized Successfully" << std::endl;
std::cout << "Renderer Initializing..." << std::endl;
renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
if (renderer == NULL)
{
std::cout << "Renderer Creation Failed : " << SDL_GetError() << std::endl;
pause
QuitGame();
}
else
{
std::cout << "Renderer Initialized Successfully" << std::endl;
// This line (under) crashes game, and crashes visual studio...
FPS_Text_Surface = TTF_RenderText_Solid(Sans, "Frames Passed : " + FramesPassed, Color_White);
testImg = IMG_LoadTexture(renderer, "images/test.bmp");
FPS_Text = SDL_CreateTextureFromSurface(renderer, FPS_Text_Surface);
}
}
}
}
std::cout << "Game Has Successfully Initialized!" << std::endl;
return 0;
}
void InitRects()
{
sprite1_Rect.h = 32;
sprite1_Rect.w = 32;
sprite1_Rect.x = 10;
sprite1_Rect.y = 10;
FPS_Text_Rect.h = 100;
FPS_Text_Rect.w = 50;
FPS_Text_Rect.x = 2;
FPS_Text_Rect.y = 2;
}
void processInput()
{
if (SDL_PollEvent(&evnt)) {
switch (evnt.type) {
case SDL_QUIT:
QuitGame();
break;
case SDL_KEYDOWN:
switch (evnt.key.keysym.sym) {
case SDLK_a:
sprite1_Rect.x -= 1;
break;
case SDLK_d:
sprite1_Rect.x += 1;
break;
case SDLK_w:
sprite1_Rect.y-= 1;
break;
case SDLK_s:
sprite1_Rect.y += 1;
break;
}
break;
}
}
}
void QuitGame()
{
isRunning = false;
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();
}
The problem is that you have the font as a global variable and load it straight away!
You need to call TTF_Init() first and load the font after!
By using a global vairable your loading it before initializing SDL_TTF, and this way TTF_OpenFont() will return a nullptr and if you try to read a nullptr gives an Access violation reading location 0x00000000 error!
Just call TTF_OpenFont() in a function and after TTF_Init() and it will work!
Just a tip you should check that Sans isn't a nullptr before using it!
I'm developing in VS2013 on a Windows 8.1 machine. The window flashes briefly on the screen (despite having a 2 second delay in the code).
Here is all the code:
#include <SDL.h>
#include <iostream>
int main(int argc, char **argv)
{
if (SDL_Init(SDL_INIT_EVERYTHING) != 0){
std::cout << "SDL_Init Error: " << SDL_GetError() << std::endl;
return 4;
}
//open a window
SDL_Window *win = SDL_CreateWindow("Hello World!", 100, 100, 640, 480, SDL_WINDOW_SHOWN);
if (win == nullptr){
std::cout << "SDL_CreateWindow Error: " << SDL_GetError() << std::endl;
return 3;
}
//renderer
SDL_Renderer *ren = SDL_CreateRenderer(win, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
if (ren == nullptr){
std::cout << "SDL_CreateRenderer Error: " << SDL_GetError() << std::endl;
return 2;
}
//load bitmap
SDL_Surface *bmp = SDL_LoadBMP("helloworld.jpg");
if (bmp == nullptr){
std::cout << "SDL_LoadBMP Error: " << SDL_GetError() << std::endl;
return 6;
}
SDL_Texture *tex = SDL_CreateTextureFromSurface(ren, bmp);
SDL_FreeSurface(bmp);
if (tex == nullptr){
std::cout << "SDL_CreateTextureFromSurface Error: " << SDL_GetError() << std::endl;
return 5;
}
SDL_RenderClear(ren);
SDL_RenderCopy(ren, tex, NULL, NULL);
SDL_RenderPresent(ren);
SDL_Delay(2000);
return 0;
}
It exits with a code 6. I was thinking it couldn't find the helloworld.jpg file. But, its there. I moved it from location to location hoping I was just an idiot. No luck. Its currently in the same directory as the .exe file.
SDL_LoadBMP will only load BMP formatted pictures, and guessing by the extension you have chosen you look to be using a JPEG formatted image, and your program is refusing to load it.
see SDL_Image for one possible solution.
My current code is as follows:
#include <iostream>
#include "SDL.h"
#include "SDL_image.h"
int main(int argc, char **argv) {
if (SDL_Init(SDL_INIT_EVERYTHING != 0)) {
std::cout << "SDL_Init() Error: " << SDL_GetError() << std::endl;
std::cin.get();
return 1;
}
SDL_Window *win = SDL_CreateWindow("RandomSDL2", 100, 100, 1280, 720, SDL_WINDOW_SHOWN);
if (win = nullptr) {
std::cout << "SDL_CreateWindow() Error: " << SDL_GetError() << std::endl;
std::cin.get();
return 1;
}
SDL_Renderer *ren = SDL_CreateRenderer(win, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
if (ren == nullptr) {
std::cout << "SDL_CreateRenderer() Error: " << SDL_GetError() << std::endl;
std::cin.get();
return 1;
}
SDL_Surface *img = IMG_Load("res/test.png");
if (img == nullptr) {
std::cout << "IMG_Load() Error: " << IMG_GetError() << std::endl;
std::cin.get();
return 1;
}
SDL_Texture *tex = SDL_CreateTextureFromSurface(ren, img);
SDL_FreeSurface(img);
if (tex == nullptr) {
std::cout << "SDL_CreateTextureFromSurface() Error: " << SDL_GetError << std::endl;
std::cin.get();
}
SDL_RenderClear(ren);
SDL_RenderCopy(ren, tex, NULL, NULL);
SDL_RenderPresent(ren);
SDL_Delay(2000);
SDL_DestroyTexture(tex);
SDL_DestroyRenderer(ren);
SDL_DestroyWindow(win);
SDL_Quit();
return 0;
}
It seems that the CreateRenderer function throws the error Invalid Window, I'm unsure as to why, I'm currently following this tutorial, I've copied the code down to a T besides the resolution and the use of SDL_image, SDL_image shouldn't really effect the creation of the renderer at this stage, I've also tried the resolution specified in the tutorial and it seems to still throw the same error.
Does anyone have any insight on this issue?
if (win = nullptr) {
^ assignment, probably wanted ==
Don't set win to nullptr and it probably won't be nullptr.