Situation
I am working on an SDL2 program and I want to remove the black terminal window that shows up everytime I fire the program,
its kinda annoying to have a black window randomly in my screen :/
What I've Tried
I've tried looking up in Google but nothing actually shows up that can fix my situation
Here's The Rest Of My Code
#include <stdio.h>
#include <SDL.h>
int main(int argc, char **args) {
// SDL Window Declaration
SDL_Surface* screen;
SDL_Window* window;
SDL_Rect plrBox;
SDL_Rect plrMot;
plrMot.x = 1;
plrMot.y = 1;
plrBox.x = 0;
plrBox.y = 0;
plrBox.w = 10;
plrBox.h = 10;
// SDL Initialization
if (SDL_Init(SDL_INIT_EVERYTHING) < 0) {
printf("Fail At SDL_Init()\n");
return 1;
}
// Window Creation
window = SDL_CreateWindow(
"Paint",
SDL_WINDOWPOS_UNDEFINED,
SDL_WINDOWPOS_UNDEFINED,
400,
300,
SDL_WINDOW_SHOWN
);
if (!window) {
printf("Fail at SDL_CreateWindow\n");
}
// Surface Creation
screen = SDL_GetWindowSurface(window);
if (!screen) {
printf("Fail at Screen\n");
return 1;
}
int run = 1;
while (run) {
SDL_FillRect(screen, NULL, SDL_MapRGB(screen->format, 255, 255, 255));
SDL_FillRect(screen, &plrBox, SDL_MapRGB(screen->format, 0, 0, 0));
plrBox.x += plrMot.x;
plrBox.y += plrMot.y;
if (plrBox.y > 300) {
plrMot.y = -plrMot.y;
}
if (plrBox.x > 400) {
plrMot.x = -plrMot.x;
}
if (plrBox.y < 0) {
plrMot.y = -plrMot.y;
}
if (plrBox.x < 0) {
plrMot.x = -plrMot.x;
}
SDL_Event events;
while (SDL_PollEvent(&events)){
switch (events.type) {
case SDL_QUIT:
run = 0;
}
}
SDL_UpdateWindowSurface(window);
}
// Quit
window = NULL;
screen = NULL;
SDL_Quit();
return 0;
}
I use mingw for all the comments out there
Related
I have this code that is setting up a window, along with the close button functionality.
#include <stdio.h>
#include <stdbool.h>
#include <SDL2/SDL.h>
int initialize();
void handle_input();
typedef struct {
SDL_Renderer *renderer;
SDL_Window *window;
bool running;
int FPS;
int width;
int height;
bool close_requested;
} Game;
Game game = {
.running = true,
.FPS = 60,
.width = 600,
.height = 600,
.close_requested = false,
};
int main(int argc, char* argv[]) {
initialize();
handle_input();
while(game.running) { //Game loop
SDL_SetRenderDrawColor(game.renderer, 255, 0, 0, 255);
SDL_RenderPresent(game.renderer);
SDL_Delay(1000/game.FPS);
} //End of game loop
SDL_DestroyRenderer(game.renderer);
SDL_DestroyWindow(game.window);
SDL_Quit();
return 0;
}
int initialize() {
if (SDL_Init(SDL_INIT_VIDEO|SDL_INIT_TIMER) != 0) { //return 0 on success
printf("error initializing SDL: %s\n", SDL_GetError());
return 1;
}
SDL_Window* window = SDL_CreateWindow("Window", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, game.width, game.height, 0); //creates window
if (!window) {
printf("error creating window: %s\n", SDL_GetError());
SDL_Quit();
return 1;
}
Uint32 render_flags = SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC; //creates a renderer
game.renderer = SDL_CreateRenderer(window, -1, render_flags);
if (!game.renderer) {
printf("error creating renderer: %s\n", SDL_GetError());
SDL_DestroyWindow(window);
SDL_Quit();
return 1;
}
}
void handle_input() {
SDL_Event event;
while (!game.close_requested) { //close button
while (SDL_PollEvent(&event)) {
if (event.type == SDL_QUIT) {
game.close_requested = true;
game.running = false;
}
}
}
}
However, whenever I try to run this program, the window won't even open and I'm getting 0 errors in the console, besides a warning that states control may reach end of non-void function at the initialize() function. What does that warning mean? What is going on with my code? What did I do wrong?
I see 2 issues here:
you call handle_input() in your main before you enter the main loop and it gets stuck there until you exit, so SDL_RenderPresent() is never called.
the initialize function doesn't return anything in case of success, this is why you see the warning.
Try with the following changes, in main() move your input handling inside the loop:
int main(int argc, char* argv[]) {
initialize();
while(game.running && !game.close_requested) {
handle_input(); // <-- move here
SDL_SetRenderDrawColor(game.renderer, 255, 0, 0, 255);
SDL_RenderPresent(game.renderer);
SDL_Delay(1000/game.FPS);
}
// the rest...
}
In initialize() add a return 0; at the end.
In handle_input() remove the outer loop:
void handle_input() {
SDL_Event event;
while (SDL_PollEvent(&event)) {
if (event.type == SDL_QUIT) {
game.close_requested = true;
game.running = false;
}
}
}
I've been working on a game with SDL2 and C, and this is my code so far:
#include <stdio.h>
#include <stdbool.h>
#include <SDL2/SDL.h>
#define BLOCK_SIZE 50
#define SPEED 5
int initialize();
void handle_input();
void draw_player();
typedef struct {
SDL_Renderer *renderer;
SDL_Window *window;
bool running;
int FPS;
int width;
int height;
bool close_requested;
int input[256];
} Game;
Game game = {
.running = true,
.FPS = 60,
.width = 600,
.height = 600,
.close_requested = false,
.input = {},
};
SDL_Rect player = {
.x = 300,
.y = 300,
.w = BLOCK_SIZE,
.h = BLOCK_SIZE
};
int main(int argc, char* argv[]) {
initialize();
while(game.running && !game.close_requested) { //Game loop
SDL_SetRenderDrawColor(game.renderer, 0, 0, 0, 255);
SDL_RenderClear(game.renderer);
handle_input();
draw_player();
SDL_RenderPresent(game.renderer);
SDL_Delay(1000/game.FPS);
} //End of game loop
SDL_DestroyRenderer(game.renderer);
SDL_DestroyWindow(game.window);
SDL_Quit();
return 0;
}
int initialize() {
if (SDL_Init(SDL_INIT_VIDEO|SDL_INIT_TIMER) != 0) { //return 0 on success
printf("error initializing SDL: %s\n", SDL_GetError());
return 1;
}
game.window = SDL_CreateWindow("Window", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, game.width, game.height, 0); //creates window
if (!game.window) {
printf("error creating window: %s\n", SDL_GetError());
SDL_Quit();
return 1;
}
Uint32 render_flags = SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC; //creates a renderer
game.renderer = SDL_CreateRenderer(game.window, -1, render_flags);
if (!game.renderer) {
printf("error creating renderer: %s\n", SDL_GetError());
SDL_DestroyWindow(game.window);
SDL_Quit();
return 1;
}
return 0;
}
void handle_input() {
SDL_Event event;
while (SDL_PollEvent(&event)) {
if (event.type == SDL_QUIT) {
game.close_requested = true;
game.running = false;
}
//printf("input: %p code: %i\n", game.input, event.key.keysym.scancode);
if (event.type == SDL_KEYDOWN) {
game.input[event.key.keysym.scancode] = true;
//printf("True");
}
if (event.type == SDL_KEYUP) {
game.input[event.key.keysym.scancode] = false;
//printf("False");
}
if (game.input[SDL_SCANCODE_UP]) {
player.y -= SPEED;
} else if (game.input[SDL_SCANCODE_DOWN]) {
player.y += SPEED;
} else if (game.input[SDL_SCANCODE_LEFT]) {
player.x -= SPEED;
} else if (game.input[SDL_SCANCODE_RIGHT]) {
player.x += SPEED;
}
}
}
void draw_player() {
SDL_SetRenderDrawColor(game.renderer, 0, 200, 50, 255);
SDL_RenderFillRect(game.renderer, &player);
}
I'm using an array called int input[] within the typedef struct, and within the handle_input() function, I'm using the array like this:
if (event.type == SDL_KEYDOWN) {
game.input[event.key.keysym.scancode] = true;
}
if (event.type == SDL_KEYUP) {
game.input[event.key.keysym.scancode] = false;
}
So that I can easily check if a key is pressed like this:
if (game.input[SDL_SCANCODE_UP]) {
//do something
}
However, when this code is run, the movement is broken up and choppy, and there is a slight delay when you press the key down. I've set the SDL_Delay to 60 FPS, so this shouldn't be an issue with that. The issue must be with the way I'm handling the inputs. Why isn't the input code firing at a consistent and fast rate?
I have recently started learning game programming in C. I am using a virtual studio code on linux Ubuntu, and image star.png is not displaying on the screen, there are no errors or problems reported by vs code. I have tried reinstalling sdl2-dev and sdl2-image-dev libraries. Maybe it is a problem with SDL, or maybe with my code (it was written in 2013).
The code should draw a white ractangl, which i can move around, on a blue screen and place a star in upper left corner of a window. It does everything except placing a star.
The code: (doesn't show "Cannot dinf star.png!" so I guess it is not that)
#include <SDL2/SDL.h>
#include <SDL2/SDL_image.h>
#include <stdio.h>
typedef struct
{
int x, y;
short life;
char *name;
}Man;
typedef struct
{
//players
Man man;
//image
SDL_Texture *star;
} GameState;
/////////////////////////////////////////////////////////////////////processEvents
int processEvents(SDL_Window *window , GameState *game)
{
SDL_Event event;
int done = 0;
//Check for events
while (SDL_PollEvent(&event))
{
switch (event.type)
{
case SDL_WINDOWEVENT_CLOSE:
{
if (window)
{
SDL_DestroyWindow(window);
window = NULL;
done = 1;
}
}
break;
case SDL_KEYDOWN:
{
switch (event.key.keysym.sym)
{
case SDLK_ESCAPE:
done = 1;
break;
}
}
break;
case SDL_QUIT:
done = 1;
break;
}
}
const Uint8 *state = SDL_GetKeyboardState(NULL);
if(state[SDL_SCANCODE_LEFT])
{
game->man.x -= 1;
}
if(state[SDL_SCANCODE_RIGHT])
{
game->man.x += 1;
}
if(state[SDL_SCANCODE_UP])
{
game->man.y -= 1;
}
if(state[SDL_SCANCODE_DOWN])
{
game->man.y += 1;
}
SDL_Delay(10);
return done;
}
/////////////////////////////////////////////////////////////////////////////////////doRender
void doRedner(SDL_Renderer *renderer, GameState *game)
{
SDL_SetRenderDrawColor(renderer , 0, 0, 255, 255); //blue
//screen clean up into blue
SDL_RenderClear(renderer);
//set color
SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);
SDL_Rect rect = {game->man.x, game->man.y, 80, 80};
SDL_RenderFillRect(renderer, &rect);
//draw a star
SDL_Rect starRect = { 50, 50, 64, 64 };
SDL_RenderCopy(renderer, game->star, NULL, &starRect);
SDL_RenderPresent(renderer);
}
/////////////////////////////////////////////////////////////////////////////////////main funkction
int main(int argc, char *argv[])
{
GameState gameState;
SDL_Window *window = NULL;
SDL_Renderer *renderer = NULL;
SDL_Surface *starSurface = NULL;
SDL_Init(SDL_INIT_VIDEO);
gameState.man.x = 340-40;
gameState.man.y = 240-40;
window = SDL_CreateWindow("Game Widnow",
SDL_WINDOWPOS_UNDEFINED,
SDL_WINDOWPOS_UNDEFINED,
640,
480,
0
);
renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
//load image
starSurface = IMG_Load("star.png");
if(starSurface = NULL)
{
printf("Cannot find star.png!\n\n");
SDL_Quit();
return 1;
}
gameState.star = SDL_CreateTextureFromSurface(renderer, starSurface);
SDL_FreeSurface(starSurface);
int done = 0;
while(!done)
{
//check events
done = processEvents(window, &gameState);
//render
doRedner(renderer, &gameState);
}
SDL_Delay(1000);
//exit game and free memory
SDL_DestroyTexture(gameState.star);
//destroy and close window
SDL_DestroyWindow(window);
SDL_DestroyRenderer(renderer);
SDL_Quit();
return 0;
}
TL;DR: Your intention is to perform a comparison, but you are using the assignment operator (i.e., =) instead of the comparison operator ==.
The conditional expression in your if statement:
if(starSurface = NULL)
{
...
}
does not check whether starSurface is NULL. The expression starSurface = NULL assigns NULL to starSurface and evaluates to NULL. Therefore, the condition evaluates to false and no error message is displayed.
Instead, you should write (note the double = below):
if (starSurface == NULL)
or just:
if (!starSurface)
I'm working through Lazy Foo's SDL2 tutorials and stuck trying to render multiple viewports. The idea is to load a PNG as a texture, create SDL_Rect structs for 3 different viewports (top left, top right, bottom), then copy the texture onto each viewport, and finally render all 3 viewports. My code is only rendering the first viewport.
I've tried changing the order - in every case, whichever viewport is defined first is the only one that renders.
I also tried changing the viewport dimensions, in case overlap was the issue - same problem.
The only question I found about multiple viewports didn't point me in the right direction. But it did start me thinking - my code is written in C, the tutorial in C++. Although I think I'm translating everything correctly (the other lessons work fine), maybe I'm missing something obvious here?
I'm compiling with CFLAGS = -Wall -Wextra -pedantic -std=c99 - no warnings or errors.
Edit: I tried rendering filled rectangles instead of a loaded PNG, but the issue is the same - only the first one renders.
Here's my code:
#include <SDL2/SDL.h>
#include <SDL2/SDL_image.h>
#include <stdio.h>
#define SCREEN_WIDTH 640
#define SCREEN_HEIGHT 480
int init_renderer();
int load_media();
SDL_Texture *load_texture(char *);
void close_renderer();
SDL_Window *g_window = NULL;
SDL_Renderer *g_renderer = NULL;
SDL_Texture *g_texture = NULL;
int main()
{
if (init_renderer() != 1) {
return -1;
}
if (!SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, "1")) {
printf("Warning: Linear texture filtering not enabled!\n");
}
if (load_media() != 1) {
return -1;
}
int quit = 0;
SDL_Event e;
while (quit != 1) {
while (SDL_PollEvent(&e) != 0) {
if (e.type == SDL_QUIT || e.key.keysym.sym == SDLK_q) {
quit = 1;
}
}
SDL_SetRenderDrawColor(g_renderer, 0xff, 0xff, 0xff, 0xff);
SDL_RenderClear(g_renderer);
SDL_Rect top_left_vp;
top_left_vp.x = 0;
top_left_vp.y = 0;
top_left_vp.w = SCREEN_WIDTH / 2;
top_left_vp.h = SCREEN_HEIGHT / 2;
SDL_RenderSetViewport(g_renderer, &top_left_vp);
SDL_RenderCopy(g_renderer, g_texture, NULL, NULL);
SDL_Rect top_right_vp;
top_right_vp.x = SCREEN_WIDTH / 2;
top_right_vp.y = 0;
top_right_vp.w = SCREEN_WIDTH / 2;
top_right_vp.h = SCREEN_HEIGHT / 2;
SDL_RenderSetViewport(g_renderer, &top_right_vp);
SDL_RenderCopy(g_renderer, g_texture, NULL, NULL);
SDL_Rect bottom_vp;
bottom_vp.x = 0;
bottom_vp.y = SCREEN_HEIGHT / 2;
bottom_vp.w = SCREEN_WIDTH;
bottom_vp.h = SCREEN_HEIGHT / 2;
SDL_RenderSetViewport(g_renderer, &bottom_vp);
SDL_RenderCopy(g_renderer, g_texture, NULL, NULL);
SDL_RenderPresent(g_renderer);
}
close_renderer();
return 0;
}
int init_renderer()
{
if (SDL_Init(SDL_INIT_VIDEO) < 0) {
printf("Failed to initialize SDL. Error: %s\n", SDL_GetError());
return 0;
}
g_window = SDL_CreateWindow("SDL Tuts",
SDL_WINDOWPOS_UNDEFINED,
SDL_WINDOWPOS_UNDEFINED,
SCREEN_WIDTH,
SCREEN_HEIGHT,
SDL_WINDOW_SHOWN);
if (g_window == NULL) {
printf("Failed to create window. Error: %s\n", SDL_GetError());
return 0;
}
g_renderer = SDL_CreateRenderer(g_window, -1, SDL_RENDERER_ACCELERATED);
if (g_renderer == NULL) {
printf("Failed to create renderer. Error: %s\n", SDL_GetError());
return 0;
}
SDL_SetRenderDrawColor(g_renderer, 0x29, 0xAB, 0x87, 0xFF);
int img_flags = IMG_INIT_PNG;
if (!(IMG_Init(img_flags) & img_flags)) {
printf("Failed to initialize SDL Image. SDL_Image Error: %s\n", IMG_GetError());
return 0;
}
return 1;
}
int load_media()
{
g_texture = load_texture("assets/texture.png");
if (g_texture == NULL) {
return 0;
}
return 1;
}
SDL_Texture *load_texture(char *path)
{
SDL_Texture *new_texture = NULL;
SDL_Surface *loaded_surface = IMG_Load(path);
if (loaded_surface == NULL) {
printf("Failed to load image. SDL_Image Error: %s\n", IMG_GetError());
} else {
new_texture = SDL_CreateTextureFromSurface(g_renderer, loaded_surface);
if (new_texture == NULL) {
printf("Failed to create texture from %s. Error: %s\n", path, SDL_GetError());
}
SDL_FreeSurface(loaded_surface);
}
return new_texture;
}
void close_renderer()
{
SDL_DestroyTexture(g_texture);
g_texture = NULL;
SDL_DestroyRenderer(g_renderer);
SDL_DestroyWindow(g_window);
g_renderer = NULL;
g_window = NULL;
IMG_Quit();
SDL_Quit();
}
To check for more errors, you should see what the calls to SDL_RenderSetViewPort are returning. According to the docs, it returns an int, which is 0 on success or a negative int if there's an error. It's entirely possible that something deeper in SDL is having a fit.
Additional pro tips: you can define the SDL_Rect structs outside of your while loop to save a miniscule margin of processing power. And to spare yourself some typing, you can initialize a SDL_Rect using a list constructor instead of manually punching each property. E.G.:
SDL_Rect top_left_vp;
top_left_vp.x = 0;
top_left_vp.y = 0;
top_left_vp.w = SCREEN_WIDTH / 2;
top_left_vp.h = SCREEN_HEIGHT / 2;
is more simply
SDL_Rect top_left_vp = {
0,
0,
SCREEN_WIDTH / 2,
SCREEN_HEIGHT / 2
};
The screen is always black. Tell me how to display the sprites correctly.
This is my code:
#define SHAPE_SIZE 32
void aff_map(SDL_Renderer *renderer)
{
SDL_Surface *img;
SDL_Texture *Tfloor
int x = 0;
int y = 0;
int map[4][8] = {{0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0},
{0,0,0,0,0,0,0,0}};
SDL_Rect SrcR;
SDL_Rect DestR;
DestR.x = 0;
DestR.y = 0;
DestR.w = SHAPE_SIZE;
DestR.h = SHAPE_SIZE;
img = IMG_Load("floor.bmp");
Tfloor = SDL_CreateTextureFromSurface(renderer, img);
while (y < 4)
{
x = 0;
while (x < 8)
{
if (map[y][x] == 0)
SDL_RenderCopy(renderer, Tfloor, NULL, &DestR);
x++;
DestR.x = DestR.x + 32;
}
DestR.x = 0;
DestR.y = DestR.y + 32;
y++;
}
SDL_RenderPresent(renderer);
}
int main()
{
SDL_Window *screen;
SDL_Event evenements;
SDL_Renderer *renderer;
screen = SDL_CreateWindow("Zappy", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 8 * SHAPE_SIZE -32, 4 * SHAPE_SIZE, 0);
renderer = SDL_CreateRenderer(screen, -1, SDL_RENDERER_ACCELERATED);
SDL_RenderClear(renderer);
while (42)
{
SDL_WaitEvent(&evenements);
if (evenements.window.event == SDL_WINDOWEVENT_CLOSE ||
evenements.key.keysym.sym == SDLK_ESCAPE)
{
SDL_DestroyWindow(screen);
SDL_Quit();
break;
}
aff_map(renderer);
}
return 0;
}
The error message is explicit.
It says that the "floor.bmp" has not been converted to a surface.
It means that 'img' parameter is NULL.
Try the following :
Specify the full path to your picture in IMG_Load(), for example "/home/quentin/floor.bmp"
Check the return value of IMG_Load().