Initial commit

src/engine/input.c

@@ -0,0 +1,99 @@
+#include "engine/input.h"
+#include <string.h>
+
+static bool s_current[ACTION_COUNT];
+static bool s_previous[ACTION_COUNT];
+
+/*
+ * Latched states: accumulate press/release events across frames
+ * so that a press is never lost even if no update tick runs
+ * during the frame it was detected.
+ */
+static bool s_latched_pressed[ACTION_COUNT];
+static bool s_latched_released[ACTION_COUNT];
+
+static bool s_quit_requested;
+
+/* Default key bindings (primary + alternate) */
+static SDL_Scancode s_bindings[ACTION_COUNT] = {
+    [ACTION_LEFT]  = SDL_SCANCODE_LEFT,
+    [ACTION_RIGHT] = SDL_SCANCODE_RIGHT,
+    [ACTION_UP]    = SDL_SCANCODE_UP,
+    [ACTION_DOWN]  = SDL_SCANCODE_DOWN,
+    [ACTION_JUMP]  = SDL_SCANCODE_Z,
+    [ACTION_SHOOT] = SDL_SCANCODE_X,
+    [ACTION_DASH]  = SDL_SCANCODE_C,
+    [ACTION_PAUSE] = SDL_SCANCODE_ESCAPE,
+};
+
+/* Alternate bindings (0 = no alternate) */
+static SDL_Scancode s_alt_bindings[ACTION_COUNT] = {
+    [ACTION_SHOOT] = SDL_SCANCODE_SPACE,
+};
+
+void input_init(void) {
+    memset(s_current, 0, sizeof(s_current));
+    memset(s_previous, 0, sizeof(s_previous));
+    memset(s_latched_pressed, 0, sizeof(s_latched_pressed));
+    memset(s_latched_released, 0, sizeof(s_latched_released));
+    s_quit_requested = false;
+}
+
+void input_poll(void) {
+    /* Save previous state */
+    memcpy(s_previous, s_current, sizeof(s_current));
+    s_quit_requested = false;
+
+    /* Process SDL events */
+    SDL_Event event;
+    while (SDL_PollEvent(&event)) {
+        switch (event.type) {
+        case SDL_QUIT:
+            s_quit_requested = true;
+            break;
+        }
+    }
+
+    /* Read keyboard state */
+    const Uint8 *keys = SDL_GetKeyboardState(NULL);
+    for (int i = 0; i < ACTION_COUNT; i++) {
+        s_current[i] = keys[s_bindings[i]];
+        if (s_alt_bindings[i] && keys[s_alt_bindings[i]]) {
+            s_current[i] = true;
+        }
+
+        /* Latch edges: once set, stays true until consumed */
+        if (s_current[i] && !s_previous[i]) {
+            s_latched_pressed[i] = true;
+        }
+        if (!s_current[i] && s_previous[i]) {
+            s_latched_released[i] = true;
+        }
+    }
+}
+
+void input_consume(void) {
+    /* Clear latched states after an update tick has read them */
+    memset(s_latched_pressed, 0, sizeof(s_latched_pressed));
+    memset(s_latched_released, 0, sizeof(s_latched_released));
+}
+
+bool input_pressed(Action a) {
+    return s_latched_pressed[a];
+}
+
+bool input_held(Action a) {
+    return s_current[a];
+}
+
+bool input_released(Action a) {
+    return s_latched_released[a];
+}
+
+bool input_quit_requested(void) {
+    return s_quit_requested;
+}
+
+void input_shutdown(void) {
+    /* Nothing to clean up */
+}