image.cpp: remove unused macros, in-place conversion from rgba to argb.

main.cpp: change move assignment in generic raii wrapper, change the Interpreter from struct to class to better reflect what it actually is.
window.cpp: implement a workaround for the window to not freeze during dragging. fuck you ms.

src/image.cpp

@@ -9,9 +9,6 @@
 #include <cstdint>
 #include <image.h>
 
-#define STR2(x) #x
-#define STR(x) STR2(x)
-
 extern "C" {
 uint32_t* image_load(const char* filename, int* width, int* height) {
     int n;
@@ -41,7 +38,7 @@ uint32_t* image_load_resized(const char* filename, int desired_width, int desire
     if (!data) return nullptr;
 
     // Allocate buffer for resized image
-    unsigned char* resized = (unsigned char*)malloc(desired_width * desired_height * 4);
+    uint32_t* resized = (uint32_t*)malloc(desired_width * desired_height * 4);
     if (!resized) {
         stbi_image_free(data);
         return nullptr;
@@ -49,26 +46,25 @@ uint32_t* image_load_resized(const char* filename, int desired_width, int desire
     
     // Resize the image
     stbir_resize_uint8_linear(data, original_width, original_height, 0,
-                              resized, desired_width, desired_height, 0,
+                              (unsigned char* )resized, desired_width, desired_height, 0,
                               STBIR_RGBA);
     
     stbi_image_free(data);
 
-    // Convert RGBA to ARGB
-    uint32_t* out = (uint32_t*)malloc(desired_width * desired_height * sizeof(uint32_t));
-    if (!out) {
-        free(resized);
-        return nullptr;
-    }
+    // In-place conversion from RGBA to ARGB
+    // We iterate backwards to ensure we don't overwrite bytes before reading them,
+    // though since we are working within the same 4-byte boundaries, forward works too!
     for (int i = 0; i < desired_width * desired_height; ++i) {
-        uint8_t r = resized[4*i + 0];
-        uint8_t g = resized[4*i + 1];
-        uint8_t b = resized[4*i + 2];
-        uint8_t a = resized[4*i + 3];
-        out[i] = (a << 24) | (r << 16) | (g << 8) | b;
+        uint8_t* pixel = (uint8_t*)&resized[i];
+        uint8_t r = pixel[0];
+        uint8_t g = pixel[1];
+        uint8_t b = pixel[2];
+        uint8_t a = pixel[3];
+
+        resized[i] = ((uint32_t)a << 24) | ((uint32_t)r << 16) | ((uint32_t)g << 8) | b;
     }
-    free(resized);
-    return out;
+
+    return resized;
 }
 
 void image_free(uint32_t* data) {