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buggy, but better, mouse zoom works most of the time, a strange bug occures when x and y are near zero, sdl then takes no mouse events anymore

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ti_mo
2026-05-29 16:37:06 +02:00
parent 847a445a79
commit 2541f26dda
1 changed files with 20 additions and 9 deletions
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SimpleImageViewer.c
+20 -9
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@@ -95,12 +95,25 @@ int clamp_low(const int in, const int low){
return in < low ? low : in;
}
void on_wheel(SDL_Event* event, SDL_Window* window){
printf("a");
void on_wheel(SDL_Event* event, SDL_Window* window) {
int last_w, last_h;
SDL_GetWindowSize(window, &last_w, &last_h);
int new_w = clamp_low(last_w + (int)event->wheel.y, 50);
SDL_SetWindowSize(window, new_w, new_w * last_h / last_w);
int step = event->wheel.y * 25;
int new_w = clamp_low(last_w + step, 50);
int new_h = new_w * last_h / last_w;
int dx = new_w - last_w;
int dy = new_h - last_h;
int x, y;
SDL_GetWindowPosition(window, &x, &y);
x -= dx / 2;
y -= dy / 2;
SDL_SetWindowPosition(window, x, y);
SDL_SetWindowSize(window, new_w, new_h);
}
int main(int argc, char** argv){
@@ -122,8 +135,6 @@ int main(int argc, char** argv){
exit(3);
}
printf("Dimensions: Width = %d, Height = %d\n", image.x, image.y);
SDL_Window* window = create_window("SimpleImageViewer", image.x, image.y);
if(!window){
printf("Failed to create window!");
@@ -160,14 +171,14 @@ int main(int argc, char** argv){
if(event.type == SDL_EVENT_QUIT || event.type == SDL_EVENT_WINDOW_CLOSE_REQUESTED) run = false;
if(event.type == SDL_EVENT_MOUSE_BUTTON_DOWN && event.button.button == SDL_BUTTON_LEFT){
drag_mouse = true;
last_pointer_x = (int)event.motion.x;
last_pointer_y = (int)event.motion.y;
last_pointer_x = (int)event.button.x;
last_pointer_y = (int)event.button.y;
}
if(event.type == SDL_EVENT_MOUSE_BUTTON_UP && event.button.button == SDL_BUTTON_LEFT) drag_mouse = false;
if(event.type == SDL_EVENT_MOUSE_MOTION && drag_mouse){
int last_x, last_y;
SDL_GetWindowPosition(window, &last_x, &last_y);
SDL_SetWindowPosition(window, last_x + (int)event.motion.x - last_pointer_x, last_y + (int)event.motion.y - last_pointer_y);
SDL_SetWindowPosition(window, last_x + (int)event.button.x - last_pointer_x, last_y + (int)event.button.y - last_pointer_y);
}
if(event.type == SDL_EVENT_MOUSE_WHEEL){
on_wheel(&event, window);