septag / Dds Ktx

dds-ktx: Portable single header DDS/KTX reader for C/C++

@septag

• Parses from memory blob. No allocations
• No dependencies
• Single-header for easy integration
• Overridable libc functions

Build Example (ctexview)

ctexview is a tiny ddx-ktx viewer that can be built on linux/mac and windows. To build it just compile the single file with your compiler.

Windows:

cl ctexview.c /O2

Linux:

gcc ctexview.c -O2 -lGL -ldl -lX11 -lXi -lXcursor -lm -o ctexview

to view images just provide the image path as an argument:

ctexview [dds_or_ktx_image_file_path]

Used open-source libraries for app creation/graphics: Sokol

Keys:

• UP/DOWN: change current mipmap
• Apostrophe: change text color
• F: Next cube-map face
• R: Toggle Red channel
• G: Toggle Green channel
• B: Toggle Blue channel
• A: Toggle Alpha channel

Usage

In this example, a simple 2D texture is parsed and created using OpenGL

#define DDSKTX_IMPLEMENT
#include "dds-ktx.h"

int size;
void* dds_data = load_file("test.dds", &size);
assert(dds_data);
ddsktx_texture_info tc = {0};
GLuint tex = 0;
if (ddsktx_parse(&tc, dds_data, size, NULL)) {
    assert(tc.depth == 1);
    assert(!(tc.flags & STC_TEXTURE_FLAG_CUBEMAP));
    assert(tc.num_layers == 1);

    //Create GPU texture from tc data
    glGenTextures(1, &tex);
    glActiveTexture(GL_TEXTURE0);
    glBindTexture(img->gl_target, tex);

    for (int mip = 0; mip < tc->num_mips; mip++) {
        ddsktx_sub_data sub_data;
        ddsktx_get_sub(&tc, &sub_data, dds_data, size, 0, 0, mip);
        // Fill/Set texture sub resource data (mips in this case)
        if (ddsktx_format_compressed(tc.format))
            glCompressedTexImage2D(..);
        else
            glTexImage2D(..);
    }

    // Now we can delete file data
    free(dds_data);
}

Links

• DdsKtxSharp: C# port of dds-ktx by Roman Shapiro

TODO

• Write KTX/DDS
• Read KTX metadata. currently it just stores the offset/size to the metadata block

Others

• stb_image - Single header library that loads images (.png, .jpg, .bmp, etc)
• bimg - Extensive C++ image library

NOTE: Many parts of the code is taken from bimg library.

License (BSD 2-clause)

Copyright 2018 Sepehr Taghdisian. All rights reserved.

https://github.com/septag/dds-ktx

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

   1. Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.

   2. Redistributions in binary form must reproduce the above copyright notice,
      this list of conditions and the following disclaimer in the documentation
      and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY COPYRIGHT HOLDER ``AS IS'' AND ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
EVENT SHALL COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
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