mrmBot-Matrix/natives/mirror.cc
2023-03-15 10:09:09 -04:00

64 lines
2.4 KiB
C++

#include <vips/vips8>
#include "common.h"
using namespace std;
using namespace vips;
char *Mirror(string type, string *outType, char *BufferData,
size_t BufferLength, ArgumentMap Arguments, size_t *DataSize) {
bool vertical = GetArgumentWithFallback<bool>(Arguments, "vertical", false);
bool first = GetArgumentWithFallback<bool>(Arguments, "first", false);
VOption *options = VImage::option()->set("access", "sequential");
VImage in =
VImage::new_from_buffer(BufferData, BufferLength, "",
type == "gif" ? options->set("n", -1) : options)
.colourspace(VIPS_INTERPRETATION_sRGB);
if (!in.has_alpha()) in = in.bandjoin(255);
VImage out;
if (vertical) {
if (type == "gif") {
// once again, libvips gif handling is both a blessing and a curse
vector<VImage> img;
int pageHeight = vips_image_get_page_height(in.get_image());
int nPages = vips_image_get_n_pages(in.get_image());
bool isOdd = pageHeight % 2;
for (int i = 0; i < nPages; i++) {
int x = (i * pageHeight) + (first ? 0 : (pageHeight / 2));
VImage cropped = in.crop(0, x, in.width(), pageHeight / 2);
VImage flipped = cropped.flip(VIPS_DIRECTION_VERTICAL);
VImage final = VImage::arrayjoin(
{first ? cropped : flipped, first ? flipped : cropped},
VImage::option()->set("across", 1));
img.push_back(final);
}
out = VImage::arrayjoin(img, VImage::option()->set("across", 1));
out.set(VIPS_META_PAGE_HEIGHT, pageHeight - (isOdd ? 1 : 0));
} else {
VImage cropped = in.extract_area(0, 0, in.width(), in.height() / 2);
VImage flipped = cropped.flip(VIPS_DIRECTION_VERTICAL);
out = VImage::arrayjoin({cropped, flipped},
VImage::option()->set("across", 1));
}
} else {
if (first) {
VImage cropped = in.extract_area(0, 0, in.width() / 2, in.height());
VImage flipped = cropped.flip(VIPS_DIRECTION_HORIZONTAL);
out = VImage::arrayjoin({cropped, flipped});
} else {
int size = in.width() / 2;
VImage cropped = in.extract_area(size, 0, size, in.height());
VImage flipped = cropped.flip(VIPS_DIRECTION_HORIZONTAL);
out = VImage::arrayjoin({flipped, cropped});
}
}
void *buf;
out.write_to_buffer(("." + *outType).c_str(), &buf, DataSize);
return (char *)buf;
}