Commit Graph

1043 Commits

Author SHA1 Message Date
Brecht Van Lommel
74caf77361 Cycles: add option to specify OptiX runtime root directory
This allows individual users or Linux distributions to specify a directory
Cycles will automatically look for the OptiX include folder, to compile kernels
at runtime.

It is still possible to override this with the OPTIX_ROOT_DIR environment
variable at runtime.

Based on patch by Sebastian Parborg.

Ref D15792
2022-08-29 19:50:20 +02:00
Sebastian Parborg
8ffc11dbcb Cleanup OpenGL linking and related code after libepoxy merge
This cleans up the OpenGL build flags and linking.
It additionally also removes some dead code.

One of these dead code paths is WITH_X11_ALPHA which actually never was
active even with the build flag on. The call to use this was never
called because the default initializer for GHOST was set to have it off
per default. Nothing called this function with a boolean value to enable it.

These cleanups are needed to support true headless OpenGL rendering.
Without these cleanups libepoxy will fail to load the correct OpenGL
Libraries as we have already linked them to the blender binary.

Reviewed By: Brecht, Campbell, Jeroen

Differential Revision: http://developer.blender.org/D15554
2022-08-15 16:47:20 +02:00
Christian Rauch
a296b8f694 GPU: replace GLEW with libepoxy
With libepoxy we can choose between EGL and GLX at runtime, as well as
dynamically open EGL and GLX libraries without linking to them.

This will make it possible to build with Wayland, EGL, GLVND support while
still running on systems that only have X11, GLX and libGL. It also paves
the way for headless rendering through EGL.

libepoxy is a new library dependency, and is included in the precompiled
libraries. GLEW is no longer a dependency, and WITH_SYSTEM_GLEW was removed.

Includes contributions by Brecht Van Lommel, Ray Molenkamp, Campbell Barton
and Sergey Sharybin.

Ref T76428

Differential Revision: https://developer.blender.org/D15291
2022-08-15 16:10:29 +02:00
Patrick Mours
79787bf8e1 Cycles: Improve denoiser update performance when rendering with multiple GPUs
This patch causes the render buffers to be copied to the denoiser
device only once before denoising and output/display is then fed
from that single buffer on the denoiser device. That way usually all
but one copy (from all the render devices to the denoiser device)
can be eliminated, provided that the denoiser device is also the
display device (in which case interop is used to update the display).
As such this patch also adds some logic that tries to ensure the
chosen denoiser device is the same as the display device.

Differential Revision: https://developer.blender.org/D15657
2022-08-12 16:00:54 +02:00
Xavier Hallade
d706d0460c Cycles oneAPI: simplify num_concurrent_states selection
The number of Execution Units and resident "threads" (simd width * threads
per EUs) are now exposed and used to select the number of states using
a simplified heuristic.
2022-07-27 09:45:33 +02:00
Brecht Van Lommel
f26aa186b2 Cleanup: remove __KERNEL_CPU__
This was tested in some places to check if code was being compiled for the
CPU, however this is only defined in the kernel. Checking __KERNEL_GPU__
always works.
2022-07-25 17:43:35 +02:00
Brecht Van Lommel
011d3c75a7 Cleanup: compiler warning 2022-07-15 15:20:53 +02:00
Brecht Van Lommel
523bbf7065 Cycles: generalize shader sorting / locality heuristic to all GPU devices
This was added for Metal, but also gives good results with CUDA and OptiX.
Also enable it for future Apple GPUs instead of only M1 and M2, since this has
been shown to help across multiple GPUs so the better bet seems to enable
rather than disable it.

Also moves some of the logic outside of the Metal device code, and always
enables the code in the kernel since other devices don't do dynamic compile.

Time per sample with OptiX + RTX A6000:
                                         new                  old
barbershop_interior                      0.0730s              0.0727s
bmw27                                    0.0047s              0.0053s
classroom                                0.0428s              0.0464s
fishy_cat                                0.0102s              0.0108s
junkshop                                 0.0366s              0.0395s
koro                                     0.0567s              0.0578s
monster                                  0.0206s              0.0223s
pabellon                                 0.0158s              0.0174s
sponza                                   0.0088s              0.0100s
spring                                   0.1267s              0.1280s
victor                                   0.0524s              0.0531s
wdas_cloud                               0.0817s              0.0816s

Ref D15331, T87836
2022-07-15 13:42:47 +02:00
Michael Jones
da4ef05e4d Cycles: Apple Silicon optimization to specialize intersection kernels
The Metal backend now compiles and caches a second set of kernels which are
optimized for scene contents, enabled for Apple Silicon.

The implementation supports doing this both for intersection and shading
kernels. However this is currently only enabled for intersection kernels that
are quick to compile, and already give a good speedup. Enabling this for
shading kernels would be faster still, however this also causes a long wait
times and would need a good user interface to control this.

M1 Max samples per minute (macOS 13.0):

                    PSO_GENERIC  PSO_SPECIALIZED_INTERSECT  PSO_SPECIALIZED_SHADE

barbershop_interior       83.4	            89.5                   93.7
bmw27                   1486.1	          1671.0                 1825.8
classroom                175.2	           196.8                  206.3
fishy_cat                674.2	           704.3                  719.3
junkshop                 205.4	           212.0                  257.7
koro                     310.1	           336.1                  342.8
monster                  376.7	           418.6                  424.1
pabellon                 273.5	           325.4                  339.8
sponza                   830.6	           929.6                 1142.4
victor                    86.7              96.4                   96.3
wdas_cloud               111.8	           112.7                  183.1

Code contributed by Jason Fielder, Morteza Mostajabodaveh and Michael Jones

Differential Revision: https://developer.blender.org/D14645
2022-07-15 13:40:04 +02:00
Brecht Van Lommel
79da7f2a8f Cycles: refactor to move part of KernelData definition to template header
To be used for specialization on Metal in a following commit, turning these
members into compile time constants.

Ref D14645
2022-07-15 13:40:04 +02:00
Michael Jones
4b1d315017 Cycles: Improve cache usage on Apple GPUs by chunking active indices
This patch partitions the active indices into chunks prior to sorting by material in order to tradeoff some material coherence for better locality. On Apple Silicon GPUs (particularly higher end M1-family GPUs), we observe overall render time speedups of up to 15%. The partitioning is implemented by repeating the range of `shader_sort_key` for each partition, and encoding a "locator" key which distributes the indices into sorted chunks.

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D15331
2022-07-14 14:26:18 +01:00
Xavier Hallade
41c10ac84a Cycles: fix support for multiple Intel GPUs
Identical Intel GPUs ended up with the same id.
Added PCI BDF to the id to make it unique.
2022-07-01 11:20:00 +02:00
Campbell Barton
b6c28002ac Cleanup: spelling in comments 2022-06-30 12:14:22 +10:00
Xavier Hallade
a02992f131 Cycles: Add support for rendering on Intel GPUs using oneAPI
This patch adds a new Cycles device with similar functionality to the
existing GPU devices.  Kernel compilation and runtime interaction happen
via oneAPI DPC++ compiler and SYCL API.

This implementation is primarly focusing on Intel® Arc™ GPUs and other
future Intel GPUs.  The first supported drivers are 101.1660 on Windows
and 22.10.22597 on Linux.

The necessary tools for compilation are:
- A SYCL compiler such as oneAPI DPC++ compiler or
  https://github.com/intel/llvm
- Intel® oneAPI Level Zero which is used for low level device queries:
  https://github.com/oneapi-src/level-zero
- To optionally generate prebuilt graphics binaries: Intel® Graphics
  Compiler All are included in Linux precompiled libraries on svn:
  https://svn.blender.org/svnroot/bf-blender/trunk/lib The same goes for
  Windows precompiled binaries but for the graphics compiler, available
  as "Intel® Graphics Offline Compiler for OpenCL™ Code" from
  https://www.intel.com/content/www/us/en/developer/articles/tool/oneapi-standalone-components.html,
  for which path can be set as OCLOC_INSTALL_DIR.

Being based on the open SYCL standard, this implementation could also be
extended to run on other compatible non-Intel hardware in the future.

Reviewed By: sergey, brecht

Differential Revision: https://developer.blender.org/D15254

Co-authored-by: Nikita Sirgienko <nikita.sirgienko@intel.com>
Co-authored-by: Stefan Werner <stefan.werner@intel.com>
2022-06-29 12:58:04 +02:00
Sayak Biswas
abfa09752f Cycles: enable Vega GPU/APU support
Enables Vega and Vega II GPUs as well as Vega APU, using changes in HIP code
to support 64-bit waves and a new HIP SDK version.

Tested with Radeon WX9100, Radeon VII GPUs and Ryzen 7 PRO 5850U with Radeon
Graphics APU.

Ref T96740, T91571

Differential Revision: https://developer.blender.org/D15242
2022-06-28 18:35:43 +02:00
Brecht Van Lommel
9b6e86ace1 Cycles: stop Metal rendering on command buffer error
If there is an error we should stop rendering, instead of finishing with a
wrong render result or reporting a wrong benchmark time.

Ref T96519

Differential Revision: https://developer.blender.org/D15287
2022-06-24 16:51:56 +02:00
Brecht Van Lommel
a5ff46e0fc Cleanup: make format 2022-06-23 19:28:39 +02:00
Michael Jones
d8e9647ae2 Cycles: Add diagnostic tracing of MTLLibrary compilation time
Reviewed By: sergey

Differential Revision: https://developer.blender.org/D15268
2022-06-23 10:06:20 +01:00
Michael Jones
532b33973b Cycles: Tidy of KernelData patchup code
Reviewed By: sergey

Differential Revision: https://developer.blender.org/D15267
2022-06-22 22:38:00 +01:00
Michael Jones
328a911379 Cycles: Distinguish Apple GPUs by core count
This patch suffixes Apple GPU device names with `(GPU - # cores)` so that variant GPUs with the same chipset can be distinguished. Currently benchmark scores for these M1 family GPUs are being incorrectly merged:

- M1: 7 or 8 cores
- M1 Pro: 14 or 16 cores
- M1 Max: 24 or 32 cores
- M1 Ultra: 48 or 64 cores

Reviewed By: brecht, sergey

Differential Revision: https://developer.blender.org/D15257
2022-06-22 22:32:56 +01:00
Brecht Van Lommel
ff1883307f Cleanup: renaming and consistency for kernel data
* Rename "texture" to "data array". This has not used textures for a long time,
  there are just global memory arrays now. (On old CUDA GPUs there was a cache
  for textures but not global memory, so we used to put all data in textures.)
* For CUDA and HIP, put globals in KernelParams struct like other devices.
* Drop __ prefix for data array names, no possibility for naming conflict now that
  these are in a struct.
2022-06-20 12:30:48 +02:00
Brecht Van Lommel
2c1bffa286 Cleanup: add verbose logging category names instead of numbers
And use them more consistently than before.
2022-06-17 14:08:14 +02:00
Michael Jones
19e0b60f3e Cycles: MetalDeviceQueue - capture of multiple dispatches, and some tidying
This patch adds a new mode of gpu capture (env var `CYCLES_DEBUG_METAL_CAPTURE_SAMPLES`) to capture a block of dispatches between "reset" calls. It also fixes member data naming inconsistencies and adds some missing OS version checks.

Screenshot showing .gputrace capture in Xcode 14.0 beta (using `CYCLES_DEBUG_METAL_CAPTURE_SAMPLES="1"` and `CYCLES_DEBUG_METAL_CAPTURE_LIMIT="10"`):

{F13155703}

Reviewed By: sergey, brecht

Differential Revision: https://developer.blender.org/D15179
2022-06-13 13:42:07 +01:00
Sergey Sharybin
0fddff027e Cleanup: Unused but set variable in Cycles Metal profiler 2022-06-09 10:20:26 +02:00
Michael Jones
4412e14708 Cycles: Useful Metal backend debug & profiling functionality
This patch adds some useful debugging & profiling env vars to the Metal backend:

- `CYCLES_METAL_PROFILING`: output a per-kernel timing report at the end of the render
- `CYCLES_METAL_DEBUG`: enable per-dispatch tracing (very verbose)
- `CYCLES_DEBUG_METAL_CAPTURE_KERNEL`: enable programatic .gputrace capture for a specified kernel index

Here's an example of the timing report with `CYCLES_METAL_PROFILING` enabled:

```
---------------------------------------------------------------------------------------------------
Kernel name                                 Total threads   Dispatches     Avg. T/D    Time   Time%
---------------------------------------------------------------------------------------------------
integrator_init_from_camera                   657,407,232          161    4,083,274   0.24s   0.51%
integrator_intersect_closest                1,629,288,440          681    2,392,494  15.18s  32.12%
integrator_intersect_shadow                   751,652,291          470    1,599,260   5.80s  12.28%
integrator_shade_background                   304,612,074          263    1,158,220   1.16s   2.45%
integrator_shade_surface                    1,159,764,041          676    1,715,627  20.57s  43.52%
integrator_shade_shadow                       598,885,847          418    1,432,741   1.27s   2.69%
integrator_queued_paths_array               2,969,650,130          805    3,689,006   0.35s   0.74%
integrator_queued_shadow_paths_array          593,936,619          379    1,567,115   0.14s   0.29%
integrator_terminated_paths_array              22,205,417          155      143,260   0.05s   0.10%
integrator_sorted_paths_array               2,517,140,043          676    3,723,579   1.65s   3.50%
integrator_compact_paths_array                648,912,748          155    4,186,533   0.03s   0.07%
integrator_compact_states                      20,872,687          155      134,662   0.14s   0.29%
integrator_terminated_shadow_paths_array      374,100,675          438      854,111   0.16s   0.33%
integrator_compact_shadow_paths_array         503,768,657          438    1,150,156   0.05s   0.10%
integrator_compact_shadow_states               37,664,941          202      186,460   0.23s   0.50%
integrator_reset                               25,165,824            6    4,194,304   0.06s   0.12%
film_convert_combined_half_rgba                 3,110,400            6      518,400   0.00s   0.01%
prefix_sum                                            676          676            1   0.19s   0.40%
---------------------------------------------------------------------------------------------------
                                                                 6,760               47.27s 100.00%
---------------------------------------------------------------------------------------------------
```

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D15044
2022-06-07 11:08:39 +01:00
Patrick Mours
5c6053ccb1 Fix misaligned address error when rendering 3D curves in the viewport with Cycles and OptiX 7.4
Acceleration structures in the viewport default to building with the fast
build flag, but the intersection program used for curves was queried with
the fast trace flag. The resulting mismatch caused an exception in the
intersection kernel. Since it's difficult to predict whether dynamic or static
acceleration structures are going to be built at the time of kernel loading,
this fixes the mismatch by always using the fast trace flag for curves.
2022-06-03 12:24:13 +02:00
Campbell Barton
61a7e5be18 Cleanup: '*' prefix C-comment blocks 2022-06-01 15:38:48 +10:00
Brecht Van Lommel
610619c203 Merge branch 'blender-v3.2-release' 2022-05-31 17:35:16 +02:00
Brecht Van Lommel
f2cd7e08fe Fix Cycles MNEE not working for Metal
Move MNEE to own kernel, separate from shader ray-tracing. This does introduce
the limitation that a shader can't use both MNEE and AO/bevel, but that seems
like the better trade-off for now.

We can experiment with bigger kernel organization changes later.

Differential Revision: https://developer.blender.org/D15070
2022-05-31 17:24:43 +02:00
Patrick Mours
a8c81ffa83 Cycles: Add half precision float support for volumes with NanoVDB
This patch makes it possible to change the precision with which to
store volume data in the NanoVDB data structure (as float, half, or
using variable bit quantization) via the previously unused precision
field in the volume data block.
It makes it possible to further reduce memory usage during
rendering, at a slight cost to the visual detail of a volume.

Differential Revision: https://developer.blender.org/D10023
2022-05-23 19:08:01 +02:00
Campbell Barton
427a2c920a Cleanup: spelling in comments, capitalize tags
Also add missing task-ID reference & remove colon after \note as it
doesn't render properly in doxygen.
2022-05-13 09:29:25 +10:00
Michael Jones
007184bcf2 Enable inlining on Apple Silicon. Use new process-wide ShaderCache in order to safely re-enable binary archives
This patch is the same as D14763, but with a fix for unit test failures caused by ShaderCache fetch logic not working in the non-MetalRT case:

```
diff --git a/intern/cycles/device/metal/kernel.mm b/intern/cycles/device/metal/kernel.mm
index ad268ae7057..6aa1a56056e 100644
--- a/intern/cycles/device/metal/kernel.mm
+++ b/intern/cycles/device/metal/kernel.mm
@@ -203,9 +203,12 @@ bool kernel_has_intersection(DeviceKernel device_kernel)

   /* metalrt options */
   request.pipeline->use_metalrt = device->use_metalrt;
-  request.pipeline->metalrt_hair = device->kernel_features & KERNEL_FEATURE_HAIR;
-  request.pipeline->metalrt_hair_thick = device->kernel_features & KERNEL_FEATURE_HAIR_THICK;
-  request.pipeline->metalrt_pointcloud = device->kernel_features & KERNEL_FEATURE_POINTCLOUD;
+  request.pipeline->metalrt_hair = device->use_metalrt &&
+                                   (device->kernel_features & KERNEL_FEATURE_HAIR);
+  request.pipeline->metalrt_hair_thick = device->use_metalrt &&
+                                         (device->kernel_features & KERNEL_FEATURE_HAIR_THICK);
+  request.pipeline->metalrt_pointcloud = device->use_metalrt &&
+                                         (device->kernel_features & KERNEL_FEATURE_POINTCLOUD);

   {
     thread_scoped_lock lock(cache_mutex);
@@ -225,9 +228,9 @@ bool kernel_has_intersection(DeviceKernel device_kernel)

   /* metalrt options */
   bool use_metalrt = device->use_metalrt;
-  bool metalrt_hair = device->kernel_features & KERNEL_FEATURE_HAIR;
-  bool metalrt_hair_thick = device->kernel_features & KERNEL_FEATURE_HAIR_THICK;
-  bool metalrt_pointcloud = device->kernel_features & KERNEL_FEATURE_POINTCLOUD;
+  bool metalrt_hair = use_metalrt && (device->kernel_features & KERNEL_FEATURE_HAIR);
+  bool metalrt_hair_thick = use_metalrt && (device->kernel_features & KERNEL_FEATURE_HAIR_THICK);
+  bool metalrt_pointcloud = use_metalrt && (device->kernel_features & KERNEL_FEATURE_POINTCLOUD);

   MetalKernelPipeline *best_pipeline = nullptr;
   for (auto &pipeline : collection) {

```

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D14923
2022-05-11 16:20:59 +01:00
Campbell Barton
12a1fa9cf4 Cleanup: format 2022-05-06 18:27:44 +10:00
Patrick Mours
6fa5d520b8 Cycles: Add support for parallel compilation of OptiX module
OptiX 7.4 adds support for splitting the costly creation of an OptiX
module into smaller tasks that can be executed in parallel on a
thread pool.
This is only really relevant for the "shader_raytrace" kernel variant
as the main one is small and compiles fast either way. It sheds of
a few seconds there (total gain is not massive currently, since it is
difficult for the compiler to split up the huge shading entry point
that is the primary one taking up time, but it is still measurable).

Differential Revision: https://developer.blender.org/D14845
2022-05-05 14:35:41 +02:00
Brecht Van Lommel
52a5f68562 Revert "Cycles: Enable inlining on Apple Silicon for 1.1x speedup"
This reverts commit b82de02e7c. It is causing
crashes in various regression tests.

Ref D14763
2022-04-28 00:46:43 +02:00
Michael Jones
b82de02e7c Cycles: Enable inlining on Apple Silicon for 1.1x speedup
This is a stripped down version of D14645 without the scene specialisation optimisations.

The two major changes in this patch are:

- Enables more aggressive inlining on Apple Silicon resulting in a 1.1x speedup and 10% reduction in spill, at the cost of longer pipeline build times
- Revival of shader binary archives through a new ShaderCache which is shared between MetalDevice instances using the same physical MTLDevice. This mitigates the extra compile times via explicit caching (rather than, as before, relying on the implicit system shader cache which can be purged without notice)

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D14763
2022-04-26 22:17:16 +01:00
Sergey Sharybin
eccc9d8eba Cleanup: Remove unused function in Cycles queue
Noticed while looking into oneAPI patch.

Seems to be unused, without clear indication why/when it might be
needed. Removing the function simplifies adding the new backend.

Differential Revision: https://developer.blender.org/D14652
2022-04-19 10:32:07 +02:00
Brecht Van Lommel
2cb76a6c8d Cleanup: consistently use parallel_for without tbb namespace in Cycles 2022-04-18 19:14:36 +02:00
Brecht Van Lommel
2d472b70e5 Revert "Cycles: enable HIP for Vega and Vega II (Radeon 7) GPUs on Windows"
This is not currently working, reverting until the driver/compiler has a fix.

This reverts commit c46e58817c.
2022-04-12 19:18:58 +02:00
Brecht Van Lommel
0de0950ad5 Cycles: various Linux build fixes related to Hydra render delegate
* Add missing GLEW and hgiGL libraries for Hydra
* Fix wrong case sensitive include
* Fix link errors by adding external libs to static Hydra lib
* Work around weird Hydra link error with MAX_SAMPLES
* Use Embree by default for Hydra
* Sync external libs code with standalone
* Update version number to match Blender
* Remove unneeded CLEW/GLEW from test executable

None of this should affect Cycles in Blender.

Ref T96731
2022-04-07 19:52:53 +02:00
Brian Savery
c46e58817c Cycles: enable HIP for Vega and Vega II (Radeon 7) GPUs on Windows
Basic testing on windows only so far. Will need some testing on Linux as well
when the Linux enablement patch is ready.

Does not enable Vega APUs yet (which would be gfx902 or gfx90c).

Differential Revision: https://developer.blender.org/D14432
2022-03-24 01:12:45 +01:00
Patrick Mours
d350976ba0 Cycles: Add Hydra render delegate
This patch adds a Hydra render delegate to Cycles, allowing Cycles to be used for rendering
in applications that provide a Hydra viewport. The implementation was written from scratch
against Cycles X, for integration into the Blender repository to make it possible to continue
developing it in step with the rest of Cycles. For this purpose it follows the style of the rest of
the Cycles code and can be built with a CMake option
(`WITH_CYCLES_HYDRA_RENDER_DELEGATE=1`) similar to the existing standalone version
of Cycles.

Since Hydra render delegates need to be built against the exact USD version and other
dependencies as the target application is using, this is intended to be built separate from
Blender (`WITH_BLENDER=0` CMake option) and with support for library versions different
from what Blender is using. As such the CMake build scripts for Windows had to be modified
slightly, so that the Cycles Hydra render delegate can e.g. be built with MSVC 2017 again
even though Blender requires MSVC 2019 now, and it's possible to specify custom paths to
the USD SDK etc. The codebase supports building against the latest USD release 22.03 and all
the way back to USD 20.08 (with some limitations).

Reviewed By: brecht, LazyDodo

Differential Revision: https://developer.blender.org/D14398
2022-03-23 16:39:05 +01:00
Sergey Sharybin
8cdee3a6d4 Fix T93710: Artifacts denoising hi-res images using OPtiX
Caused by an integer overflow in the tiling utilities of OptiX SDK.

Seems for now it's easier to copy and modify code to our sources so
that we don't need to bump SDK version requirement (which might lead
to an increased driver requirement as well).

There are still some fixes needed from a newer driver to have such
denoising to work properly: Windows requires 511.79, Linux 510.54.

Thanks Patrick for investigation!

Differential Revision: https://developer.blender.org/D14300
2022-03-10 16:17:59 +01:00
Brecht Van Lommel
f130d4f211 Cleanup: fix various typos
Contributed by luzpaz.

Differential Revision: https://developer.blender.org/D14203
2022-03-07 17:28:39 +01:00
Germano Cavalcante
e1ec2d0251 Merge branch 'blender-v3.1-release' 2022-03-01 16:31:18 -03:00
Michael Jones
952a613d38 Cycles: Hide MetalRT checkbox for AMD GPUs
This patch hides the MetalRT checkbox for AMD GPUs, pending fixes for MetalRT argument encoding on AMD.

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D14175
2022-03-01 16:05:47 +00:00
Jacques Lucke
472ddc6e27 Merge branch 'blender-v3.1-release' 2022-02-22 15:13:27 +01:00
Brecht Van Lommel
66f3545a0b Cleanup: compiler warning 2022-02-22 14:03:11 +01:00
Brecht Van Lommel
259f4e50ef Merge branch 'blender-v3.1-release' 2022-02-16 15:35:18 +01:00
Brecht Van Lommel
f059bdc823 Cycles: restore basic standalone GUI, now using SDL
GLUT does not support offscreen contexts, which is required for the new
display driver. So we use SDL instead. Note that this requires using a
system SDL package, the Blender precompiled SDL does not include the video
subsystem.

There is currently no text display support, instead info is printed to
the terminal. This would require adding an embedded font and GLSL shaders,
or using GUI library.

Another improvement to be made is supporting OpenColorIO display transforms,
right now we assume Rec.709 scene linear and display.

All OpenGL, GLEW and SDL code was move out of core cycles and into
app/opengl. This serves as a template for apps that want to integrate
Cycles interactive rendering, with a simple OpenGLDisplayDriver example.
In general this would be adapted to the graphics API and color management
used by the app.

Ref T91846
2022-02-16 15:30:43 +01:00