serenity/Userland/Libraries/LibGfx/PGMLoader.cpp

/*
 * Copyright (c) 2020, Hüseyin ASLITÜRK <asliturk@hotmail.com>
 * Copyright (c) 2022, the SerenityOS developers.
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include "PGMLoader.h"
#include "PortableImageLoaderCommon.h"
#include "Streamer.h"
#include <AK/Endian.h>
#include <string.h>

namespace Gfx {

static void set_adjusted_pixels(PGMLoadingContext& context, Vector<Gfx::Color> const& color_data)
{
    size_t index = 0;
    for (size_t y = 0; y < context.height; ++y) {
        for (size_t x = 0; x < context.width; ++x) {
            Color color = color_data.at(index);
            if (context.format_details.max_val < 255) {
                color = adjust_color(context.format_details.max_val, color);
            }
            context.bitmap->set_pixel(x, y, color);
            ++index;
        }
    }
}

bool read_image_data(PGMLoadingContext& context, Streamer& streamer)
{
    Vector<Gfx::Color> color_data;

    if (context.type == PGMLoadingContext::Type::ASCII) {
        u16 value;

        while (true) {
            if (!read_number(streamer, &value))
                break;

            if (!read_whitespace(context, streamer))
                break;

            color_data.append({ (u8)value, (u8)value, (u8)value });
        }
    } else if (context.type == PGMLoadingContext::Type::RAWBITS) {
        u8 pixel;
        while (streamer.read(pixel)) {
            color_data.append({ pixel, pixel, pixel });
        }
    }

    size_t context_size = (u32)context.width * (u32)context.height;
    if (context_size != color_data.size()) {
        dbgln("Not enough color data in image.");
        return false;
    }

    if (!create_bitmap(context))
        return false;

    set_adjusted_pixels(context, color_data);

    context.state = PGMLoadingContext::State::Bitmap;
    return true;
}
}