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- /*
- * Copyright (C) 2021 Christopher J. Howard
- *
- * This file is part of Antkeeper source code.
- *
- * Antkeeper source code is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * Antkeeper source code 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with Antkeeper source code. If not, see <http://www.gnu.org/licenses/>.
- */
-
- #include "image.hpp"
- #include <cstring>
- #include <stdexcept>
-
- image::image(const image& source)
- {
- *this = source;
- }
-
- image::image():
- width(0),
- height(0),
- component_size(0),
- channel_count(0),
- pixel_size(0),
- pixels(nullptr),
- size(0)
- {}
-
- image::~image()
- {
- free_pixels();
- }
-
- image& image::operator=(const image& source)
- {
- format(source.component_size, source.channel_count);
- resize(source.width, source.height);
- std::memcpy(pixels, source.pixels, size);
-
- return *this;
- }
-
- bool image::compatible(const image& other) const
- {
- return (other.component_size == component_size && other.channel_count == channel_count);
- }
-
- void image::copy(const image& source, unsigned int w, unsigned int h, unsigned int from_x, int unsigned from_y, unsigned int to_x, unsigned int to_y)
- {
- if (!compatible(source))
- {
- throw std::runtime_error("Cannot copy image with mismatched format");
- }
-
- const unsigned char* from_pixels = static_cast<const unsigned char*>(source.pixels);
- unsigned char* to_pixels = static_cast<unsigned char*>(pixels);
-
- for (unsigned int i = 0; i < h; ++i)
- {
- // Calculate vertical pixel offset
- unsigned int from_i = from_y + i;
- unsigned int to_i = to_y + i;
-
- // Bounds check
- if (from_i >= source.height || to_i >= height)
- break;
-
- for (unsigned int j = 0; j < w; ++j)
- {
- // Calculate horizontal pixel offsets
- unsigned int from_j = from_x + j;
- unsigned int to_j = to_x + j;
-
- // Bounds check
- if (from_j >= source.width || to_j >= width)
- continue;
-
- // Calculate pixel data offset (in bytes)
- std::size_t from_offset = (from_i * source.width + from_j) * pixel_size;
- std::size_t to_offset = (to_i * width + to_j) * pixel_size;
-
- // Copy single pixel
- std::memcpy(to_pixels + to_offset, from_pixels + from_offset, pixel_size);
- }
- }
- }
-
- void image::format(std::size_t component_size, std::size_t channel_count)
- {
- if (this->component_size == component_size && this->channel_count == channel_count)
- return;
-
- free_pixels();
- this->component_size = component_size;
- this->channel_count = channel_count;
- pixel_size = component_size * channel_count;
- size = width * height * pixel_size;
- allocate_pixels();
- }
-
- void image::resize(unsigned int width, unsigned int height)
- {
- if (this->width == width && this->height == height)
- {
- return;
- }
-
- free_pixels();
- this->width = width;
- this->height = height;
- size = width * height * pixel_size;
- allocate_pixels();
- }
-
- void image::allocate_pixels()
- {
- if (size != 0)
- {
- pixels = new unsigned char[size];
- }
- }
-
- void image::free_pixels()
- {
- if (pixels != nullptr)
- {
- delete[] reinterpret_cast<unsigned char*>(pixels);
- pixels = nullptr;
- size = 0;
- }
- }
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