Add SIMD versions of the invert transform

[MyreMylar]

Related to #2476.

This adds SSE2/Neon and AVX2 versions of the invert transform.

In quick performance testing the SSE2 version is about 12 times faster at Walt inversions, and AVX2 is about 13 times faster. I'd expect AVX2 performance to do better at larger image sizes. Though; there is only one operation in the invert transform and SSE2 can do four pixels at a time so there isn't as much in it as in some operations.

[MyreMylar]

I've been quick visual and performance testing with this test program:

import pygame
import timeit


def invert_walt(walt_image):
    return pygame.transform.invert(walt_image)


pygame.init()


display_surf = pygame.display.set_mode((800, 350))
walt = pygame.image.load("images/walt.png").convert_alpha()


walt_opaque = walt.convert()
walt_inverse = invert_walt(walt)


running = True

while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False

    display_surf.fill((255, 150, 255))
    display_surf.blit(walt, (0, 0))
    display_surf.blit(walt_inverse, (400, 0))

    pygame.display.flip()

time_taken = timeit.timeit(
    "invert_walt(walt)",
    setup="import pygame\n\n"
    "pygame.init()\n\n"
    "display_surf = pygame.display.set_mode((800, 350))\n\n"
    "walt = pygame.image.load('images/walt.png').convert_alpha()\n\n"
    "def invert_walt(walt_image): "
    "    return pygame.transform.invert(walt_image)",
    number=1000,
)
print("time taken to do 1000 walt inverts:", time_taken)

It is not compulsory to test with Walter - but it is traditional.

[itzpr3d4t0r]

LGTM

[Starbuck5]

Tested this out locally, gives pixel perfect results for all my test cases before and after this PR.

import random
import hashlib

import pygame

random.seed(36)


expected_hashes = [
    "82c38da441d3325c0ae6fa3fffa74b8b760a26d346a9fc7441c4433efc1210c7",
    "3b05aaa0469f40bfef54207d34f48a868c3a6fa665a76f8a6a8e7f34feb47935",
    "0192eeaf93728e40ab4e11bb5c9d85302ff927b48832fb95fbaceb69e9108813",
    "e8e41e3b0c08e81f29062520b0abee1f3104fc8a90966fbd29a2b46acd097791",
    "340cf63be38ad92cb7a4d836f82d2dcedc550c14ec68c783f203fd127184f6cc",
    "35f3d8ed7268d3f3fb54ebed760e08c85b09ae98960107e3c26f559ba4cba80f",
    "3f4dc52b63a567fd77b431c67be01a8cd0a2e5c5d18961a3f8d7d26faaf46976",
    "266377ffd231505911509d03a75f6ee757375faf5e965da3aa020322209a4486",
    "6d3ec34adca4c1337e000ec339901aef45039009c3355328eca28a5ba5df55e1",
    "edc66664ce5448c742e5848cce2dc2cbaed0383a16a46093551c40c5df37e384",
    "0fecf8c40a3ba2c67c382b2900e29cea152ecd1f74d212464d0f8b883131c57e",
    "f4ad7e15493f8c3862a5aa74ba093c4ab2d6b715939c286c52d61c636d03c1e1",
]

surf_height = 5
offset = (3, 7)


def populate_surf(surf):
    for y in range(surf.get_height()):
        for x in range(surf.get_width()):
            surf.set_at(
                (x, y),
                (
                    random.randint(0, 255),
                    random.randint(0, 255),
                    random.randint(0, 255),
                    random.randint(0, 255),
                ),
            )


hashes = []

for pixel_width in range(4, 16):

    dest = pygame.Surface((pixel_width, surf_height), pygame.SRCALPHA)
    populate_surf(dest)

    print(dest, dest.get_pitch())

    dest = dest.premul_alpha()

    dest = pygame.transform.invert(dest)

    sha256 = hashlib.sha256()
    sha256.update(pygame.image.tobytes(dest, "RGBA"))
    digest = sha256.hexdigest()

    assert digest == expected_hashes.pop(0)

    hashes.append(digest)
    # print(digest)

print(hashes)