mrmBot-Matrix/natives/snapchat.cc

84 lines
No EOL
3.1 KiB
C++

#include <napi.h>
#include <vips/vips8>
using namespace std;
using namespace vips;
Napi::Value Snapchat(const Napi::CallbackInfo &info) {
Napi::Env env = info.Env();
Napi::Object result = Napi::Object::New(env);
try {
Napi::Object obj = info[0].As<Napi::Object>();
Napi::Buffer<char> data = obj.Get("data").As<Napi::Buffer<char>>();
string caption = obj.Get("caption").As<Napi::String>().Utf8Value();
float pos =
obj.Has("pos") ? obj.Get("pos").As<Napi::Number>().FloatValue() : 0.5;
string type = obj.Get("type").As<Napi::String>().Utf8Value();
VOption *options = VImage::option()->set("access", "sequential");
VImage in =
VImage::new_from_buffer(data.Data(), data.Length(), "",
type == "gif" ? options->set("n", -1) : 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 = vips_image_get_n_pages(in.get_image());
int size = width / 20;
int textWidth = width - ((width / 25) * 2);
string font_string = "Helvetica Neue " + to_string(size);
VImage textIn =
VImage::text(("<span foreground=\"white\" background=\"#000000B2\">" +
caption + "</span>")
.c_str(),
VImage::option()
->set("rgba", true)
->set("align", VIPS_ALIGN_CENTRE)
->set("font", font_string.c_str())
->set("width", textWidth));
int bgHeight = textIn.height() + (width / 25);
textIn =
((textIn == (vector<double>){0, 0, 0, 0}).bandand())
.ifthenelse({0, 0, 0, 178}, textIn)
.embed((width / 2) - (textIn.width() / 2),
(bgHeight / 2) - (textIn.height() / 2), width, bgHeight,
VImage::option()
->set("extend", "background")
->set("background", (vector<double>){0, 0, 0, 178}));
vector<VImage> img;
for (int i = 0; i < nPages; i++) {
VImage img_frame =
type == "gif" ? in.crop(0, i * pageHeight, width, pageHeight) : in;
img_frame = img_frame.composite2(
textIn, VIPS_BLEND_MODE_OVER,
VImage::option()->set("x", 0)->set("y", pageHeight * pos));
img.push_back(img_frame);
}
VImage final = VImage::arrayjoin(img, VImage::option()->set("across", 1));
final.set(VIPS_META_PAGE_HEIGHT, pageHeight);
void *buf;
size_t length;
final.write_to_buffer(
("." + type).c_str(), &buf, &length,
type == "gif" ? VImage::option()->set("dither", 0)->set("reoptimise", 1) : 0);
result.Set("data", Napi::Buffer<char>::Copy(env, (char *)buf, length));
result.Set("type", type);
} 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;
}