In most places this is simply replaced by `std::string_view`.
We also change a few internal/private headers so they accept
`std::string_view` instead of `utils::CString`.
mipgen can now emit basis-encoded KTX2 files. Both the desktop and
web "suzanne" samples use this as a test for compressed textures.
This PR does not add KTX2 support to glTF, but it's on the way.
`BasisEncoder` has a builder style API that calls the basis encoder to
create KTX2 files. This hides some low-level BasisU features that we are
not using, like file I/O and mipmap generation.
`Ktx2Reader` is an easy-to-use API for creating Filament textures from
KTX2 files. Its API primarily consists of these two methods:
bool requestFormat(Texture::InternalFormat format);
Filament::Texture* load(const uint8_t* data, size_t size);
The first method is used to build an ordered list of formats that are
supported by your hardware. The second method consumes the contents of a
basis-encoded KTX2 file and attempts to produce a Filament texture with
a preferred format.
IMPORTANT: Our tools still let you use KTX1 for non-compressed images
because it is useful for HDR, but you can no longer use KTX1 for
block-compressed data.
Partial fix for #4771.
Changes:
- Remove the strange header-only variant of libs/image
- Rename KtxBundle => Ktx1Bundle
- Move image/KtxUtility => ktxreader/Ktx1Reader
- Add unit test for Ktx1Reader and test stub for KTX2.
Notes:
- Ktx1Bundle does not depend on Filament and is used by cmgen
and mipgen to generate KTX files.
- Ktx1Reader has a dependency on Filament and should therefore live in
a separate library, which it now does.
* Use locale-independent string->float conversion
strtof and friends are locale aware and won't parse decimal numbers
with a period ("12.6" for instance) in locales that use another
character for the decimal period ("," in French for instance).
This change introduces a new function called strtof_c that forces
the use of a specific locale (called "C") to make sure we always
parse floats in the desired "C" format ("12.6").
With C++17 we should be able to use std::from_chars but this API
is not implemented in clang for floats at the moment.
* Fix Linux
These constants are not part of the standard. We instead use our own
constexpr definitions in the filament::math namespace, as part of
the scalar.h include.
This uses strtof rather than stringstream and provides a common location
that can be leveraged by the upcoming JNI bindings.
Note that this new method lives in KtxBundle rather than KtxUtility. The
latter creates Filament textures and therefore does not get built into
libimage.
This adds some new functions to libimage for computing distance fields
and coordinate fields. This runs on the CPU but uses an efficient
algorithm. This will initially be leveraged by the baking pipeline to
dilate charts, but could be useful in other applications.
Background: with the Vulkan backend, RGB8 textures do
not work (at least not on my hadrware). This makes me unable to run some
examples, because they use normal maps in RGB8 format.
It appears that the following commit addresses the problem by adding a
special command line option to mipgen:
https://github.com/google/filament/commit/8dda07bf2c19f9ebd8ab499ca2c3849d7b1f031f
However, processing normal maps with this option does not work: certain
assertions in the image library fail.
This PR changes these functions in the image library to handle 4-channel
images instead of failing.
In a lot of case the StaticString hash can be computed a compile time,
so we now take advantage of that.
Removed StaticString(const char*) ctor, and replaced it with a
StaticString::make() method.
Fixed a couple wrong uses of the old StaticString(const char*) ctor.
When using GAUSSIAN_NORMALS, image::resampleImage automatically unitizes
its output. This means that clients (e.g. mipgen) need to ensure that
the source image is in [-1,+1] rather than [0,+1].
KtxBundle is basically an in-memory representation of a KTX file.
Our primary motivation for introducing this class is to have a
structured container for block-compressed textures.
Note that this class is defined in libimage rather than libimageio.
There are several reasons for this:
1. The texel data in a KtxBundle is not meant to be decoded by the CPU.
2. It has no dependendencies on any libraries (stb_image tinyexr etc).
3. We wish to use it with WebGL, which needs to avoid using imageio.
* Introduce mipgen frontend.
For now this is fairly simple although it does let you choose a filter.
Another cool feature is that an HTML file is generated which makes it
easy to review the generated miplevels.
This does not expose the Boundary enum to users because it has not yet
been implemented in the core Image library.
* Fix up mipgen per code review.
* Overhaul the image library, Phase I.
The preps for our upcoming mipgen command line tool by adding filtering
capabilities and unit tests for a new LinearImage class, which will
subsume Image (deprecated).
Filament's new image library is composed of three components:
- LinearImage....simple 3D tensor of floats
- ImageOps.......free functions for simple transforms
- ImageSampler...high quality filtering
The old Image class was a simple untyped data blob and is now
deprecated. The new LinearImage class is always float32, and always
stores pixels in packed scanline order. This makes it easier to
implement image-based algorithms because they can be agnostic of the
underlying format.
Remaining refactorings:
- Phase II will migrate imageio to LinearImage
- Phase III will migrate all downstream tools to LinearImage
- Phase IV will remove old the Image class
* Image library code review feedback.
When compiling with clang on Linux, the following warning is generated:
../../libs/image/src/ImageDecoder.cpp:487:13: warning: unterminated '#pragma pack (push, ...)' at end of file [-Wpragma-pack]
#pragma pack(push, 1)
^
According to [1], the correct pragma to pop the packing state from the
internal stack is "#pragma pack(pop)" rather than "#pragma pop()" which
is used currently. This commit replaces "#pragma pop()" with "#pragma
pack(pop)".
[1] http://gcc.gnu.org/onlinedocs/gcc-4.2.3/gcc/Structure_002dPacking-Pragmas.html
Ben Doherty
Mathias Agopian
Pei Jia
Philip Rideout
Romain Guy
nicebyte
gstanlo
Ben Doherty
Rich Wareham
Romain Guy