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-rw-r--r--core/io/image.cpp156
1 files changed, 103 insertions, 53 deletions
diff --git a/core/io/image.cpp b/core/io/image.cpp
index 65addaf964..21146dd80c 100644
--- a/core/io/image.cpp
+++ b/core/io/image.cpp
@@ -1341,78 +1341,126 @@ void Image::crop(int p_width, int p_height) {
void Image::rotate_90(ClockDirection p_direction) {
ERR_FAIL_COND_MSG(!_can_modify(format), "Cannot rotate in compressed or custom image formats.");
- ERR_FAIL_COND_MSG(width <= 1, "The Image width specified (" + itos(width) + " pixels) must be greater than 1 pixels.");
- ERR_FAIL_COND_MSG(height <= 1, "The Image height specified (" + itos(height) + " pixels) must be greater than 1 pixels.");
-
- int saved_width = height;
- int saved_height = width;
-
- if (width != height) {
- int n = MAX(width, height);
- resize(n, n, INTERPOLATE_NEAREST);
- }
+ ERR_FAIL_COND_MSG(width <= 0, "The Image width specified (" + itos(width) + " pixels) must be greater than 0 pixels.");
+ ERR_FAIL_COND_MSG(height <= 0, "The Image height specified (" + itos(height) + " pixels) must be greater than 0 pixels.");
bool used_mipmaps = has_mipmaps();
if (used_mipmaps) {
clear_mipmaps();
}
+ // In-place 90 degrees rotation by following the permutation cycles.
{
- uint8_t *w = data.ptrw();
- uint8_t src[16];
- uint8_t dst[16];
+ // Explanation by example (clockwise):
+ //
+ // abc da
+ // def -> eb
+ // fc
+ //
+ // In memory:
+ // 012345 012345
+ // abcdef -> daebfc
+ //
+ // Permutation cycles:
+ // (0 --a--> 1 --b--> 3 --d--> 0)
+ // (2 --c--> 5 --f--> 4 --e--> 2)
+ //
+ // Applying cycles (backwards):
+ // 0->s s=a (store)
+ // 3->0 abcdef -> dbcdef
+ // 1->3 dbcdef -> dbcbef
+ // s->1 dbcbef -> dacbef
+ //
+ // 2->s s=c
+ // 4->2 dacbef -> daebef
+ // 5->4 daebef -> daebff
+ // s->5 daebff -> daebfc
+
+ const int w = width;
+ const int h = height;
+ const int size = w * h;
+
+ uint8_t *data_ptr = data.ptrw();
uint32_t pixel_size = get_format_pixel_size(format);
- // Flip.
+ uint8_t single_pixel_buffer[16];
- if (p_direction == CLOCKWISE) {
- for (int y = 0; y < height / 2; y++) {
- for (int x = 0; x < width; x++) {
- _get_pixelb(x, y, pixel_size, w, src);
- _get_pixelb(x, height - y - 1, pixel_size, w, dst);
+#define PREV_INDEX_IN_CYCLE(index) (p_direction == CLOCKWISE) ? ((h - 1 - (index % h)) * w + (index / h)) : ((index % h) * w + (w - 1 - (index / h)))
- _put_pixelb(x, height - y - 1, pixel_size, w, src);
- _put_pixelb(x, y, pixel_size, w, dst);
+ if (w == h) { // Square case, 4-length cycles only (plus irrelevant thus skipped 1-length cycle in the middle for odd-sized squares).
+ for (int y = 0; y < h / 2; y++) {
+ for (int x = 0; x < (w + 1) / 2; x++) {
+ int current = y * w + x;
+ memcpy(single_pixel_buffer, data_ptr + current * pixel_size, pixel_size);
+ for (int i = 0; i < 3; i++) {
+ int prev = PREV_INDEX_IN_CYCLE(current);
+ memcpy(data_ptr + current * pixel_size, data_ptr + prev * pixel_size, pixel_size);
+ current = prev;
+ }
+ memcpy(data_ptr + current * pixel_size, single_pixel_buffer, pixel_size);
}
}
- } else {
- for (int y = 0; y < height; y++) {
- for (int x = 0; x < width / 2; x++) {
- _get_pixelb(x, y, pixel_size, w, src);
- _get_pixelb(width - x - 1, y, pixel_size, w, dst);
+ } else { // Rectangular case (w != h), kinda unpredictable cycles.
+ int permuted_pixels_count = 0;
+
+ for (int i = 0; i < size; i++) {
+ int prev = PREV_INDEX_IN_CYCLE(i);
+ if (prev == i) {
+ // 1-length cycle, pixel remains at the same index.
+ permuted_pixels_count++;
+ continue;
+ }
- _put_pixelb(width - x - 1, y, pixel_size, w, src);
- _put_pixelb(x, y, pixel_size, w, dst);
+ // Check whether we already processed this cycle.
+ // We iterate over it and if we'll find an index smaller than `i` then we already
+ // processed this cycle because we always start at the smallest index in the cycle.
+ // TODO: Improve this naive approach, can be done better.
+ while (prev > i) {
+ prev = PREV_INDEX_IN_CYCLE(prev);
+ }
+ if (prev < i) {
+ continue;
}
- }
- }
- // Transpose.
+ // Save the in-cycle pixel with the smallest index (`i`).
+ memcpy(single_pixel_buffer, data_ptr + i * pixel_size, pixel_size);
- for (int y = 0; y < height; y++) {
- for (int x = 0; x < width; x++) {
- if (x < y) {
- _get_pixelb(x, y, pixel_size, w, src);
- _get_pixelb(y, x, pixel_size, w, dst);
+ // Overwrite pixels one by one by the preceding pixel in the cycle.
+ int current = i;
+ prev = PREV_INDEX_IN_CYCLE(current);
+ while (prev != i) {
+ memcpy(data_ptr + current * pixel_size, data_ptr + prev * pixel_size, pixel_size);
+ permuted_pixels_count++;
- _put_pixelb(y, x, pixel_size, w, src);
- _put_pixelb(x, y, pixel_size, w, dst);
+ current = prev;
+ prev = PREV_INDEX_IN_CYCLE(current);
+ };
+
+ // Overwrite the remaining pixel in the cycle by the saved pixel with the smallest index.
+ memcpy(data_ptr + current * pixel_size, single_pixel_buffer, pixel_size);
+ permuted_pixels_count++;
+
+ if (permuted_pixels_count == size) {
+ break;
}
}
+
+ width = h;
+ height = w;
}
+
+#undef PREV_INDEX_IN_CYCLE
}
- if (saved_width != saved_height) {
- resize(saved_width, saved_height, INTERPOLATE_NEAREST);
- } else if (used_mipmaps) {
+ if (used_mipmaps) {
generate_mipmaps();
}
}
void Image::rotate_180() {
ERR_FAIL_COND_MSG(!_can_modify(format), "Cannot rotate in compressed or custom image formats.");
- ERR_FAIL_COND_MSG(width <= 1, "The Image width specified (" + itos(width) + " pixels) must be greater than 1 pixels.");
- ERR_FAIL_COND_MSG(height <= 1, "The Image height specified (" + itos(height) + " pixels) must be greater than 1 pixels.");
+ ERR_FAIL_COND_MSG(width <= 0, "The Image width specified (" + itos(width) + " pixels) must be greater than 0 pixels.");
+ ERR_FAIL_COND_MSG(height <= 0, "The Image height specified (" + itos(height) + " pixels) must be greater than 0 pixels.");
bool used_mipmaps = has_mipmaps();
if (used_mipmaps) {
@@ -1420,19 +1468,21 @@ void Image::rotate_180() {
}
{
- uint8_t *w = data.ptrw();
- uint8_t src[16];
- uint8_t dst[16];
+ uint8_t *data_ptr = data.ptrw();
uint32_t pixel_size = get_format_pixel_size(format);
- for (int y = 0; y < height / 2; y++) {
- for (int x = 0; x < width; x++) {
- _get_pixelb(x, y, pixel_size, w, src);
- _get_pixelb(width - x - 1, height - y - 1, pixel_size, w, dst);
+ uint8_t single_pixel_buffer[16];
- _put_pixelb(width - x - 1, height - y - 1, pixel_size, w, src);
- _put_pixelb(x, y, pixel_size, w, dst);
- }
+ uint8_t *from_begin_ptr = data_ptr;
+ uint8_t *from_end_ptr = data_ptr + (width * height - 1) * pixel_size;
+
+ while (from_begin_ptr < from_end_ptr) {
+ memcpy(single_pixel_buffer, from_begin_ptr, pixel_size);
+ memcpy(from_begin_ptr, from_end_ptr, pixel_size);
+ memcpy(from_end_ptr, single_pixel_buffer, pixel_size);
+
+ from_begin_ptr += pixel_size;
+ from_end_ptr -= pixel_size;
}
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-20 00:23:18 +0000