Get rid of PG_SURF_BitsPerPixel

It's inconsistent between SDL2 and SDL3, and I see no way to fix it.

In SDL2, (surf->format->BitsPerPixel), the value means the number of bits each pixel occupies in total. For example, RGBX => 32.

In SDL3, (SDL_BITSPERPIXEL(surf->format)), the value means the number of pixels occupied by the pixel's data, not including padding. So RGBX => 24.

These changes reduce SDL3 unit test failures.

Author: Starbuck5

src_c/_camera.c

@@ -126,7 +126,7 @@ surf_colorspace(PyObject *self, PyObject *arg)
     }
 
     /* check to see if the format of the surface is the same. */
-    if (PG_SURF_BitsPerPixel(surf) != PG_SURF_BitsPerPixel(newsurf)) {
+    if (PG_SURF_BytesPerPixel(surf) != PG_SURF_BytesPerPixel(newsurf)) {
         return RAISE(PyExc_ValueError, "Surfaces not the same depth");
     }
 

src_c/_pygame.h

@@ -105,7 +105,6 @@ PG_UnlockMutex(SDL_mutex *mutex)
     return 0;
 }
 
-#define PG_SURF_BitsPerPixel(surf) SDL_BITSPERPIXEL(surf->format)
 #define PG_SURF_BytesPerPixel(surf) SDL_BYTESPERPIXEL(surf->format)
 #define PG_FORMAT_BitsPerPixel(format) format->bits_per_pixel
 #define PG_FORMAT_BytesPerPixel(format) format->bytes_per_pixel
@@ -218,7 +217,6 @@ PG_UnlockMutex(SDL_mutex *mutex)
     return SDL_UnlockMutex(mutex);
 }
 
-#define PG_SURF_BitsPerPixel(surf) surf->format->BitsPerPixel
 #define PG_SURF_BytesPerPixel(surf) surf->format->BytesPerPixel
 #define PG_FORMAT_BitsPerPixel(format) format->BitsPerPixel
 #define PG_FORMAT_BytesPerPixel(format) format->BytesPerPixel

src_c/display.c

@@ -1805,7 +1805,7 @@ pg_set_mode(PyObject *self, PyObject *arg, PyObject *kwds)
         SDL_SetWindowIcon(win, pgSurface_AsSurface(state->icon));
     }
 
-    if (depth != 0 && PG_SURF_BitsPerPixel(surface->surf) != depth) {
+    if (depth != 0 && PG_SURF_BytesPerPixel(surface->surf) * 8 != depth) {
         if (PyErr_WarnEx(PyExc_DeprecationWarning,
                          "The depth argument is deprecated, and is ignored",
                          1)) {

src_c/image.c

@@ -1708,7 +1708,9 @@ SaveTGA_RW(SDL_Surface *surface, SDL_RWops *out, int rle)
     h.infolen = 0;
     SETLE16(h.cmap_start, 0);
 
-    srcbpp = PG_SURF_BitsPerPixel(surface);
+    // This bpp = Bpp*8 strategy only works on pixels a byte or larger,
+    // which are the only types of surface this function supports.
+    srcbpp = PG_SURF_BytesPerPixel(surface) * 8;
     if (srcbpp < 8) {
         SDL_SetError("cannot save <8bpp images as TGA");
         return -1;

src_c/rotozoom.c

@@ -524,8 +524,8 @@ rotozoomSurface(SDL_Surface *src, double angle, double zoom, int smooth)
     /*
      * Determine if source surface is 32bit or 8bit
      */
-    is32bit = (PG_SURF_BitsPerPixel(src) == 32);
-    if ((is32bit) || (PG_SURF_BitsPerPixel(src) == 8)) {
+    is32bit = (PG_SURF_BytesPerPixel(src) == 4);
+    if ((is32bit) || (PG_SURF_BytesPerPixel(src) == 1)) {
         /*
          * Use source surface 'as is'
          */

src_c/surface.c

@@ -441,6 +441,11 @@ surface_str(PyObject *self)
         return PyUnicode_FromString("<Surface(Dead Display)>");
     }
 
+    PG_PixelFormat *fmt = PG_GetSurfaceFormat(surf);
+    if (fmt == NULL) {
+        return RAISE(pgExc_SDLError, SDL_GetError());
+    }
+
     PyObject *colorkey = surf_get_colorkey((pgSurfaceObject *)self, NULL);
     if (colorkey == NULL) {
         return NULL;
@@ -465,7 +470,7 @@ surface_str(PyObject *self)
     // but alpha, we can "move up" the global alpha to this spot No need to do
     // this vice-versa, as it ignores extra args
     PyObject *formatted_str = PyUnicode_FromFormat(
-        format, surf->w, surf->h, PG_SURF_BitsPerPixel(surf),
+        format, surf->w, surf->h, PG_FORMAT_BitsPerPixel(fmt),
         PyObject_IsTrue(colorkey) ? colorkey : global_alpha, global_alpha);
 
     Py_DECREF(colorkey);
@@ -3114,7 +3119,12 @@ surf_get_bitsize(PyObject *self, PyObject *_null)
     SDL_Surface *surf = pgSurface_AsSurface(self);
     SURF_INIT_CHECK(surf)
 
-    return PyLong_FromLong(PG_SURF_BitsPerPixel(surf));
+    PG_PixelFormat *fmt = PG_GetSurfaceFormat(surf);
+    if (fmt == NULL) {
+        return RAISE(pgExc_SDLError, SDL_GetError());
+    }
+
+    return PyLong_FromLong(PG_FORMAT_BitsPerPixel(fmt));
 }
 
 static PyObject *

src_c/transform.c

@@ -951,7 +951,7 @@ surf_rotozoom(PyObject *self, PyObject *args, PyObject *kwargs)
         return (PyObject *)pgSurface_New(newsurf);
     }
 
-    if (PG_SURF_BitsPerPixel(surf) == 32) {
+    if (PG_SURF_BytesPerPixel(surf) == 4) {
         surf32 = surf;
         pgSurface_Lock(surfobj);
     }