mrmBot-Matrix/natives/squish.cc

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2022-10-07 18:26:12 +00:00
#include <math.h>
#include <napi.h>
#include <vips/vips8>
using namespace std;
using namespace vips;
Napi::Value Squish(const Napi::CallbackInfo &info) {
Napi::Env env = info.Env();
Napi::Object result = Napi::Object::New(env);
try {
Napi::Object obj = info[1].As<Napi::Object>();
2022-10-07 18:26:12 +00:00
Napi::Buffer<char> data = obj.Get("data").As<Napi::Buffer<char>>();
string type = obj.Get("type").As<Napi::String>().Utf8Value();
VOption *options = VImage::option();
VImage in =
VImage::new_from_buffer(
data.Data(), data.Length(), "",
type == "gif" ? options->set("n", -1)->set("access", "sequential")
: options)
.colourspace(VIPS_INTERPRETATION_sRGB);
if (!in.has_alpha())
in = in.bandjoin(255);
int width = in.width();
int pageHeight = vips_image_get_page_height(in.get_image());
int nPages = type == "gif" ? vips_image_get_n_pages(in.get_image()) : 30;
double mult = (2 * M_PI) / nPages;
vector<VImage> img;
for (int i = 0; i < nPages; i++) {
VImage img_frame =
type == "gif" ? in.crop(0, i * pageHeight, width, pageHeight) : in;
double newWidth = (sin(i * mult) / 4) + 0.75;
double newHeight = (cos(i * mult) / 4) + 0.75;
VImage resized =
img_frame.resize(newWidth, VImage::option()->set("vscale", newHeight))
.gravity(VIPS_COMPASS_DIRECTION_CENTRE, width, pageHeight);
img.push_back(resized);
}
VImage final = VImage::arrayjoin(img, VImage::option()->set("across", 1));
final.set(VIPS_META_PAGE_HEIGHT, pageHeight);
if (type != "gif") {
vector<int> delay(30, 50);
final.set("delay", delay);
}
void *buf;
size_t length;
final.write_to_buffer(".gif", &buf, &length);
result.Set("data", Napi::Buffer<char>::Copy(env, (char *)buf, length));
result.Set("type", "gif");
} catch (std::exception const &err) {
Napi::Error::New(env, err.what()).ThrowAsJavaScriptException();
} catch (...) {
Napi::Error::New(env, "Unknown error").ThrowAsJavaScriptException();
}
vips_error_clear();
vips_thread_shutdown();
return result;
}