godot/modules/bmp/image_loader_bmp.cpp
2023-10-04 19:55:11 +09:00

380 lines
16 KiB
C++

/**************************************************************************/
/* image_loader_bmp.cpp */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#include "image_loader_bmp.h"
#include "core/io/file_access_memory.h"
static uint8_t get_mask_width(uint16_t mask) {
// Returns number of ones in the binary value of the parameter: mask.
// Uses a Simple pop_count.
uint8_t c = 0u;
for (; mask != 0u; mask &= mask - 1u) {
c++;
}
return c;
}
Error ImageLoaderBMP::convert_to_image(Ref<Image> p_image,
const uint8_t *p_buffer,
const uint8_t *p_color_buffer,
const uint32_t color_table_size,
const bmp_header_s &p_header) {
Error err = OK;
if (p_buffer == nullptr) {
err = FAILED;
}
if (err == OK) {
size_t index = 0;
size_t width = (size_t)p_header.bmp_info_header.bmp_width;
size_t height = (size_t)p_header.bmp_info_header.bmp_height;
size_t bits_per_pixel = (size_t)p_header.bmp_info_header.bmp_bit_count;
// Check whether we can load it
if (bits_per_pixel == 1) {
// Requires bit unpacking...
ERR_FAIL_COND_V_MSG(width % 8 != 0, ERR_UNAVAILABLE,
vformat("1-bpp BMP images must have a width that is a multiple of 8, but the imported BMP is %d pixels wide.", int(width)));
ERR_FAIL_COND_V_MSG(height % 8 != 0, ERR_UNAVAILABLE,
vformat("1-bpp BMP images must have a height that is a multiple of 8, but the imported BMP is %d pixels tall.", int(height)));
} else if (bits_per_pixel == 2) {
// Requires bit unpacking...
ERR_FAIL_COND_V_MSG(width % 4 != 0, ERR_UNAVAILABLE,
vformat("2-bpp BMP images must have a width that is a multiple of 4, but the imported BMP is %d pixels wide.", int(width)));
ERR_FAIL_COND_V_MSG(height % 4 != 0, ERR_UNAVAILABLE,
vformat("2-bpp BMP images must have a height that is a multiple of 4, but the imported BMP is %d pixels tall.", int(height)));
} else if (bits_per_pixel == 4) {
// Requires bit unpacking...
ERR_FAIL_COND_V_MSG(width % 2 != 0, ERR_UNAVAILABLE,
vformat("4-bpp BMP images must have a width that is a multiple of 2, but the imported BMP is %d pixels wide.", int(width)));
ERR_FAIL_COND_V_MSG(height % 2 != 0, ERR_UNAVAILABLE,
vformat("4-bpp BMP images must have a height that is a multiple of 2, but the imported BMP is %d pixels tall.", int(height)));
}
// Image data (might be indexed)
Vector<uint8_t> data;
int data_len = 0;
if (bits_per_pixel <= 8) { // indexed
data_len = width * height;
} else { // color
data_len = width * height * 4;
}
ERR_FAIL_COND_V_MSG(data_len == 0, ERR_BUG, "Couldn't parse the BMP image data.");
err = data.resize(data_len);
uint8_t *data_w = data.ptrw();
uint8_t *write_buffer = data_w;
const uint32_t width_bytes = width * bits_per_pixel / 8;
const uint32_t line_width = (width_bytes + 3) & ~3;
// The actual data traversal is determined by
// the data width in case of 8/4/2/1 bit images
const uint32_t w = bits_per_pixel >= 16 ? width : width_bytes;
const uint8_t *line = p_buffer + (line_width * (height - 1));
const uint8_t *end_buffer = p_buffer + p_header.bmp_file_header.bmp_file_size - p_header.bmp_file_header.bmp_file_offset;
for (uint64_t i = 0; i < height; i++) {
const uint8_t *line_ptr = line;
for (unsigned int j = 0; j < w; j++) {
ERR_FAIL_COND_V(line_ptr >= end_buffer, ERR_FILE_CORRUPT);
switch (bits_per_pixel) {
case 1: {
uint8_t color_index = *line_ptr;
write_buffer[index + 0] = (color_index >> 7) & 1;
write_buffer[index + 1] = (color_index >> 6) & 1;
write_buffer[index + 2] = (color_index >> 5) & 1;
write_buffer[index + 3] = (color_index >> 4) & 1;
write_buffer[index + 4] = (color_index >> 3) & 1;
write_buffer[index + 5] = (color_index >> 2) & 1;
write_buffer[index + 6] = (color_index >> 1) & 1;
write_buffer[index + 7] = (color_index >> 0) & 1;
index += 8;
line_ptr += 1;
} break;
case 2: {
uint8_t color_index = *line_ptr;
write_buffer[index + 0] = (color_index >> 6) & 3;
write_buffer[index + 1] = (color_index >> 4) & 3;
write_buffer[index + 2] = (color_index >> 2) & 3;
write_buffer[index + 3] = color_index & 3;
index += 4;
line_ptr += 1;
} break;
case 4: {
uint8_t color_index = *line_ptr;
write_buffer[index + 0] = (color_index >> 4) & 0x0f;
write_buffer[index + 1] = color_index & 0x0f;
index += 2;
line_ptr += 1;
} break;
case 8: {
uint8_t color_index = *line_ptr;
write_buffer[index] = color_index;
index += 1;
line_ptr += 1;
} break;
case 16: {
uint16_t rgb = (static_cast<uint16_t>(line_ptr[1]) << 8) | line_ptr[0];
// A1R5G5B5/X1R5G5B5 => uint16_t
// [A/X]1R5G2 | G3B5 => uint8_t | uint8_t
uint8_t ba = (rgb & p_header.bmp_bitfield.alpha_mask) >> p_header.bmp_bitfield.alpha_offset; // Alpha 0b 1000 ...
uint8_t b0 = (rgb & p_header.bmp_bitfield.red_mask) >> p_header.bmp_bitfield.red_offset; // Red 0b 0111 1100 ...
uint8_t b1 = (rgb & p_header.bmp_bitfield.green_mask) >> p_header.bmp_bitfield.green_offset; // Green 0b 0000 0011 1110 ...
uint8_t b2 = (rgb & p_header.bmp_bitfield.blue_mask); // >> p_header.bmp_bitfield.blue_offset; // Blue 0b ... 0001 1111
// Next we apply some color scaling going from a variable value space to a 256 value space.
// This may be simplified some but left as is for legibility.
// float scaled_value = unscaled_value * byte_max_value / color_channel_maximum_value + rounding_offset;
float f0 = b0 * 255.0f / static_cast<float>(p_header.bmp_bitfield.red_max) + 0.5f;
float f1 = b1 * 255.0f / static_cast<float>(p_header.bmp_bitfield.green_max) + 0.5f;
float f2 = b2 * 255.0f / static_cast<float>(p_header.bmp_bitfield.blue_max) + 0.5f;
write_buffer[index + 0] = static_cast<uint8_t>(f0); // R
write_buffer[index + 1] = static_cast<uint8_t>(f1); // G
write_buffer[index + 2] = static_cast<uint8_t>(f2); // B
if (p_header.bmp_bitfield.alpha_mask_width > 0) {
write_buffer[index + 3] = ba * 0xFF; // Alpha value(Always true or false so no scaling)
} else {
write_buffer[index + 3] = 0xFF; // No Alpha channel, Show everything.
}
index += 4;
line_ptr += 2;
} break;
case 24: {
write_buffer[index + 2] = line_ptr[0];
write_buffer[index + 1] = line_ptr[1];
write_buffer[index + 0] = line_ptr[2];
write_buffer[index + 3] = 0xff;
index += 4;
line_ptr += 3;
} break;
case 32: {
write_buffer[index + 2] = line_ptr[0];
write_buffer[index + 1] = line_ptr[1];
write_buffer[index + 0] = line_ptr[2];
write_buffer[index + 3] = line_ptr[3];
index += 4;
line_ptr += 4;
} break;
}
}
line -= line_width;
}
if (p_color_buffer == nullptr || color_table_size == 0) { // regular pixels
p_image->set_data(width, height, false, Image::FORMAT_RGBA8, data);
} else { // data is in indexed format, extend it
// Palette data
Vector<uint8_t> palette_data;
palette_data.resize(color_table_size * 4);
uint8_t *palette_data_w = palette_data.ptrw();
uint8_t *pal = palette_data_w;
const uint8_t *cb = p_color_buffer;
for (unsigned int i = 0; i < color_table_size; ++i) {
pal[i * 4 + 0] = cb[2];
pal[i * 4 + 1] = cb[1];
pal[i * 4 + 2] = cb[0];
pal[i * 4 + 3] = 0xff;
cb += 4;
}
// Extend palette to image
Vector<uint8_t> extended_data;
extended_data.resize(data.size() * 4);
uint8_t *ex_w = extended_data.ptrw();
uint8_t *dest = ex_w;
const int num_pixels = width * height;
for (int i = 0; i < num_pixels; i++) {
dest[0] = pal[write_buffer[i] * 4 + 0];
dest[1] = pal[write_buffer[i] * 4 + 1];
dest[2] = pal[write_buffer[i] * 4 + 2];
dest[3] = pal[write_buffer[i] * 4 + 3];
dest += 4;
}
p_image->set_data(width, height, false, Image::FORMAT_RGBA8, extended_data);
}
}
return err;
}
Error ImageLoaderBMP::load_image(Ref<Image> p_image, Ref<FileAccess> f, BitField<ImageFormatLoader::LoaderFlags> p_flags, float p_scale) {
bmp_header_s bmp_header;
Error err = ERR_INVALID_DATA;
// A valid bmp file should always at least have a
// file header and a minimal info header
if (f->get_length() > BITMAP_FILE_HEADER_SIZE + BITMAP_INFO_HEADER_MIN_SIZE) {
// File Header
bmp_header.bmp_file_header.bmp_signature = f->get_16();
if (bmp_header.bmp_file_header.bmp_signature == BITMAP_SIGNATURE) {
bmp_header.bmp_file_header.bmp_file_size = f->get_32();
bmp_header.bmp_file_header.bmp_file_padding = f->get_32();
bmp_header.bmp_file_header.bmp_file_offset = f->get_32();
// Info Header
bmp_header.bmp_info_header.bmp_header_size = f->get_32();
ERR_FAIL_COND_V_MSG(bmp_header.bmp_info_header.bmp_header_size < BITMAP_INFO_HEADER_MIN_SIZE, ERR_FILE_CORRUPT,
vformat("Couldn't parse the BMP info header. The file is likely corrupt: %s", f->get_path()));
bmp_header.bmp_info_header.bmp_width = f->get_32();
bmp_header.bmp_info_header.bmp_height = f->get_32();
bmp_header.bmp_info_header.bmp_planes = f->get_16();
ERR_FAIL_COND_V_MSG(bmp_header.bmp_info_header.bmp_planes != 1, ERR_FILE_CORRUPT,
vformat("Couldn't parse the BMP planes. The file is likely corrupt: %s", f->get_path()));
bmp_header.bmp_info_header.bmp_bit_count = f->get_16();
bmp_header.bmp_info_header.bmp_compression = f->get_32();
bmp_header.bmp_info_header.bmp_size_image = f->get_32();
bmp_header.bmp_info_header.bmp_pixels_per_meter_x = f->get_32();
bmp_header.bmp_info_header.bmp_pixels_per_meter_y = f->get_32();
bmp_header.bmp_info_header.bmp_colors_used = f->get_32();
bmp_header.bmp_info_header.bmp_important_colors = f->get_32();
switch (bmp_header.bmp_info_header.bmp_compression) {
case BI_BITFIELDS: {
bmp_header.bmp_bitfield.red_mask = f->get_32();
bmp_header.bmp_bitfield.green_mask = f->get_32();
bmp_header.bmp_bitfield.blue_mask = f->get_32();
bmp_header.bmp_bitfield.alpha_mask = f->get_32();
bmp_header.bmp_bitfield.red_mask_width = get_mask_width(bmp_header.bmp_bitfield.red_mask);
bmp_header.bmp_bitfield.green_mask_width = get_mask_width(bmp_header.bmp_bitfield.green_mask);
bmp_header.bmp_bitfield.blue_mask_width = get_mask_width(bmp_header.bmp_bitfield.blue_mask);
bmp_header.bmp_bitfield.alpha_mask_width = get_mask_width(bmp_header.bmp_bitfield.alpha_mask);
bmp_header.bmp_bitfield.alpha_offset = bmp_header.bmp_bitfield.red_mask_width + bmp_header.bmp_bitfield.green_mask_width + bmp_header.bmp_bitfield.blue_mask_width;
bmp_header.bmp_bitfield.red_offset = bmp_header.bmp_bitfield.green_mask_width + bmp_header.bmp_bitfield.blue_mask_width;
bmp_header.bmp_bitfield.green_offset = bmp_header.bmp_bitfield.blue_mask_width;
bmp_header.bmp_bitfield.red_max = (1 << bmp_header.bmp_bitfield.red_mask_width) - 1;
bmp_header.bmp_bitfield.green_max = (1 << bmp_header.bmp_bitfield.green_mask_width) - 1;
bmp_header.bmp_bitfield.blue_max = (1 << bmp_header.bmp_bitfield.blue_mask_width) - 1;
} break;
case BI_RLE8:
case BI_RLE4:
case BI_CMYKRLE8:
case BI_CMYKRLE4: {
// Stop parsing.
ERR_FAIL_V_MSG(ERR_UNAVAILABLE,
vformat("RLE compressed BMP files are not yet supported: %s", f->get_path()));
} break;
}
// Don't rely on sizeof(bmp_file_header) as structure padding
// adds 2 bytes offset leading to misaligned color table reading
uint32_t ct_offset = BITMAP_FILE_HEADER_SIZE + bmp_header.bmp_info_header.bmp_header_size;
f->seek(ct_offset);
uint32_t color_table_size = 0;
// bmp_colors_used may report 0 despite having a color table
// for 4 and 1 bit images, so don't rely on this information
if (bmp_header.bmp_info_header.bmp_bit_count <= 8) {
// Support 256 colors max
color_table_size = 1 << bmp_header.bmp_info_header.bmp_bit_count;
ERR_FAIL_COND_V_MSG(color_table_size == 0, ERR_BUG,
vformat("Couldn't parse the BMP color table: %s", f->get_path()));
}
Vector<uint8_t> bmp_color_table;
// Color table is usually 4 bytes per color -> [B][G][R][0]
bmp_color_table.resize(color_table_size * 4);
uint8_t *bmp_color_table_w = bmp_color_table.ptrw();
f->get_buffer(bmp_color_table_w, color_table_size * 4);
f->seek(bmp_header.bmp_file_header.bmp_file_offset);
uint32_t bmp_buffer_size = (bmp_header.bmp_file_header.bmp_file_size - bmp_header.bmp_file_header.bmp_file_offset);
Vector<uint8_t> bmp_buffer;
err = bmp_buffer.resize(bmp_buffer_size);
if (err == OK) {
uint8_t *bmp_buffer_w = bmp_buffer.ptrw();
f->get_buffer(bmp_buffer_w, bmp_buffer_size);
const uint8_t *bmp_buffer_r = bmp_buffer.ptr();
const uint8_t *bmp_color_table_r = bmp_color_table.ptr();
err = convert_to_image(p_image, bmp_buffer_r,
bmp_color_table_r, color_table_size, bmp_header);
}
}
}
return err;
}
void ImageLoaderBMP::get_recognized_extensions(List<String> *p_extensions) const {
p_extensions->push_back("bmp");
}
static Ref<Image> _bmp_mem_loader_func(const uint8_t *p_bmp, int p_size) {
Ref<FileAccessMemory> memfile;
memfile.instantiate();
Error open_memfile_error = memfile->open_custom(p_bmp, p_size);
ERR_FAIL_COND_V_MSG(open_memfile_error, Ref<Image>(), "Could not create memfile for BMP image buffer.");
Ref<Image> img;
img.instantiate();
Error load_error = ImageLoaderBMP().load_image(img, memfile, false, 1.0f);
ERR_FAIL_COND_V_MSG(load_error, Ref<Image>(), "Failed to load BMP image.");
return img;
}
ImageLoaderBMP::ImageLoaderBMP() {
Image::_bmp_mem_loader_func = _bmp_mem_loader_func;
}