diff --git a/modules/bmp/image_loader_bmp.cpp b/modules/bmp/image_loader_bmp.cpp index 5b451fbf6b8..56052553672 100644 --- a/modules/bmp/image_loader_bmp.cpp +++ b/modules/bmp/image_loader_bmp.cpp @@ -32,6 +32,16 @@ #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 p_image, const uint8_t *p_buffer, const uint8_t *p_color_buffer, @@ -71,9 +81,6 @@ Error ImageLoaderBMP::convert_to_image(Ref p_image, 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))); - - } else if (bits_per_pixel == 16) { - ERR_FAIL_V_MSG(ERR_UNAVAILABLE, "16-bpp BMP images are not supported."); } // Image data (might be indexed) @@ -96,7 +103,7 @@ Error ImageLoaderBMP::convert_to_image(Ref p_image, // 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 >= 24 ? width : width_bytes; + 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; @@ -149,6 +156,34 @@ Error ImageLoaderBMP::convert_to_image(Ref p_image, index += 1; line_ptr += 1; } break; + case 16: { + uint16_t rgb = (static_cast(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_maxium_value + rounding_offset; + float f0 = b0 * 255.0f / static_cast(p_header.bmp_bitfield.red_max) + 0.5f; + float f1 = b1 * 255.0f / static_cast(p_header.bmp_bitfield.green_max) + 0.5f; + float f2 = b2 * 255.0f / static_cast(p_header.bmp_bitfield.blue_max) + 0.5f; + write_buffer[index + 0] = static_cast(f0); // R + write_buffer[index + 1] = static_cast(f1); // G + write_buffer[index + 2] = static_cast(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]; @@ -253,13 +288,32 @@ Error ImageLoaderBMP::load_image(Ref p_image, Ref f, BitField 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("Compressed BMP files are not supported: %s", f->get_path())); + 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 diff --git a/modules/bmp/image_loader_bmp.h b/modules/bmp/image_loader_bmp.h index 08b9115c87a..cb51d7f0de1 100644 --- a/modules/bmp/image_loader_bmp.h +++ b/modules/bmp/image_loader_bmp.h @@ -74,6 +74,25 @@ protected: uint32_t bmp_colors_used = 0; uint32_t bmp_important_colors = 0; } bmp_info_header; + + struct bmp_bitfield_s { + uint16_t alpha_mask = 0x8000; + uint16_t red_mask = 0x7C00; + uint16_t green_mask = 0x03E0; + uint16_t blue_mask = 0x001F; + uint16_t alpha_mask_width = 1u; + uint16_t red_mask_width = 5u; + uint16_t green_mask_width = 5u; + uint16_t blue_mask_width = 5u; + uint8_t alpha_offset = 15u; // Used for bit shifting. + uint8_t red_offset = 10u; // Used for bit shifting. + uint8_t green_offset = 5u; // Used for bit shifting. + //uint8_t blue_offset = 0u; // Always LSB aligned no shifting needed. + //uint8_t alpha_max = 1u; // Always boolean or on, so no scaling needed. + uint8_t red_max = 32u; // Used for color space scaling. + uint8_t green_max = 32u; // Used for color space scaling. + uint8_t blue_max = 32u; // Used for color space scaling. + } bmp_bitfield; }; static Error convert_to_image(Ref p_image,