quicktex/quicktex/_bindings.h

/*  Quicktex Texture Compression Library
    Copyright (C) 2021 Andrew Cassidy <drewcassidy@me.com>
    Partially derived from rgbcx.h written by Richard Geldreich <richgel99@gmail.com>
    and licenced under the public domain

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#pragma once

#include <pybind11/pybind11.h>

#include <cstdint>
#include <cstring>
#include <memory>
#include <stdexcept>

#include "Block.h"
#include "Color.h"
#include "Texture.h"

namespace pybind11::detail {
template <> struct type_caster<quicktex::Color>;
}  // namespace pybind11::detail

namespace py = pybind11;
namespace quicktex::bindings {
using namespace pybind11::literals;

template <typename T> T BufferToTexture(py::buffer buf, int width, int height) {
    static_assert(std::is_base_of<Texture, T>::value);
    static_assert(std::is_constructible<T, int, int>::value);

    auto info = buf.request(false);
    auto output = T(width, height);//std::make_shared<T>(width, height);
    auto dst_size = output.Size();

    if (info.format != py::format_descriptor<uint8_t>::format()) throw std::runtime_error("Incompatible format in python buffer: expected a byte array.");
    if (info.size < (ssize_t)dst_size) std::runtime_error("Incompatible format in python buffer: Input data is smaller than texture size.");
    if (info.ndim == 1) {
        if (info.shape[0] < (ssize_t)dst_size) throw std::runtime_error("Incompatible format in python buffer: 1-D buffer has incorrect length.");
        if (info.strides[0] != 1) throw std::runtime_error("Incompatible format in python buffer: 1-D buffer is not contiguous.");
    } else {
        throw std::runtime_error("Incompatible format in python buffer: Incorrect number of dimensions.");
    }

    std::memcpy(output.Data(), info.ptr, dst_size);

    return output;
}

template <typename B> py::class_<BlockTexture<B>> BindBlockTexture(py::module_& m, const char* name) {
    using BTex = BlockTexture<B>;

    py::type texture = py::type::of<Texture>();

    py::class_<BTex> block_texture(m, name, texture);

    block_texture.def(py::init<int, int>(), "width"_a, "height"_a);
    block_texture.def("get_block", &BTex::GetBlock, "x"_a, "y"_a);
    block_texture.def("set_block", &BTex::SetBlock, "x"_a, "y"_a, "block"_a);

    block_texture.def_static("from_bytes", &BufferToTexture<BTex>, "data"_a, "width"_a, "height"_a);

    block_texture.def_property_readonly("blocks_x", &BTex::BlocksX);
    block_texture.def_property_readonly("blocks_y", &BTex::BlocksY);
}
}  // namespace quicktex::bindings