This is an effort to be able to use the same GLSL code for both Vulkan
and OpenGL. This is done by first compiling the Vulkan GLSL code to
SPIR-V and then using a custom tool (which uses SPIRV-Cross) to convert
that back into GLSL 1.50 compatible code.
The required tool will be downloaded by CMake when glslc is found in the
path. This is included in the Vulkan SDK. To avoid having a hard
dependency on this, the generated files are included in the VCS and are
only regenerated when glslc is found on the system.
This emulates the "scrolling text" effect that is present in briefings.
It is not exactly the same since it just goes pixel wise and not by
character but it looks good enough.
This elimiates all of the remaining "old style" uniforms from our
shaders. This might not be optimal for all situations but I have
confirmed that it is at least not worse at the moment.
This is a generic way to get matrix data to shaders without using
(old-school) uniforms. This is another step towards more compatibility
with how new APIs (Vulkan) do things to increase the odds for a Vulkan
port at some point.
Persistent buffer mapping is an OpenGL technique where the contents of a
buffer object are mapped to a persistent pointer instead of having to
map and unmap a buffer every time it is modified.
This decreases the overhead for updating data in a uniform buffer object
which now only consists of a memcpy and a flush call.
This is in preparation for using persistently mapped buffers for uniform
buffers. Since that functionality is not available in the OpenGL version
we are targetting I implemented a fall-back which simply uses
glBufferSubData.
I did a benchmark with these changes and there was no change in
performance to the current master version.
This can be used for mark parts of the code which should be unreachable
in normal execution. In debug mode, if such a statement is reached an
Error dialog is shown which aborts the execution. In release mode the
macro is replaced with a compiler specific expression that lets the
compiler know that this part is unreachable which allows it to optimize
the code better.
This adds support for rendering models using thick lines (that means
lines wider than 1 pixel) which is required by the hardpoint HUD gauge.
This feature was present before the switch to OpenGL code and had to be
removed since the core profile does not support rendering lines wider
than 1 pixel.
This uses a geometry shader for converting all the triangles from a
model to 3 quads along the triangle lines which are as thick as set by
the model renderer. Geometry shaders are quite slow if they generate a
lot of geometry (and this generates 4 times the usual amount of geometry
in the shader) so it's probably not a very fast rendering operation but
it is only needed once per frame so it shouldn't be too bad.
I also added support for the RenderDoc API since I needed that for
debugging and it might be useful in the future. It will only become
active if RenderDoc is actually attached to the process so in most cases
the new code will do nothing.
This changes the decal system so that it is able to modify the normal
map of the scene. I tested this with some existing normal maps but I am
not entirely sure if the tangent matrix I construct uses the right
values so some additional testing with normal maps made specifically for
decals would be good.
This also fixed the issues introduced by the changes to how directional
lighting was handled. Now a decal can have a diffuse and a glow map. The
diffuse map is used to change the values of the color buffer and also
supports ambient lighting. The glow map renders into the emissive buffer
and should be used for effects that should not receive lighting.
This moves all lighting operations into the deferred shading phase of
the rendering pipeline. Previously, directional lights were applied to
all objects while they were being rendered. This was probably done to
avoid doing multiple full screen passes later but caused some problems
since the color information in the G-buffers was not correct for doing
later lighting operations.
This was especially noticable in dark scenes where point lights would
appear to ignore the color of the rendered objects. This should be fixed
with these changes.
I did some performance testing and to my surprise this actually improves
performance in very demanding scenes. My guess would be that applying
the shadows while rendering the objects caused a lot of overdraw which
is not the case anymore since shadows are only computed for visible
pixels. In simple scenes the opposite happens which leads to decreased
performance in those cases but in my opinion the improvement in
demanding scenes outweights this performance decrease.
This changes the model loading code such that all index and vertex data
is packed in a single GPU buffer for each data type (index and vertex
data are still in separate buffers). This reduces the amount of buffer
rebinding needed when rendering a scene which will reduce the CPU
overhead. Furthermore, this opens up possibilities of future
improvements for which it is beneficial if all data is in the same
buffer (e.g. MultiDrawIndirect rendering).
To manage where to put the data in the GPU buffer I implemented a
custom HeapAllocator which manages where data can be put. It uses a very
primitive first-fit algorithm but that is sufficient for this usage
type. This does add quite a lot of overhead while allocating GPU model
data (I did some tracing and some allocation calls took as long as
130ms).
This fixes#1457.
This allows to render screen space decals into the deferred lighting
buffers no matter how complex the underlying geometry is.
Currently there is only limited support for using this in the engine.
Only weapon impact decals are supported at the moment for testing
purposes.
One of the main points of contention when adding the NanoVG based
TrueType text rendering was that it required an external Opengl
renderer which may interfere with our rendering engine by changing
OpenGL state without telling the rest of the engine. Since the rendering
interface for NanoVG is abstract and can be easily replaced, I did just
that and replaced it with an implementation that uses only generic
graphics functions without relying on the specific graphics API.
This will improve the interoperability of NanoVG with our engine and
should make later changes to the rendering engine easier since there is
no external rendering code which may interfere with our own code.
This uses UBOs for building a buffer object of uniform data before
using that data to draw objects. This should reduce the CPU overhead by
reducing the amount of glUniform calls required for executing a single
draw call. This is especially useful if rendering is limited by the CPU
which should help performance for people with slower CPUs.
This fixes#910.
Since the system already tracks if a buffer is still in use by the GPU
the buffer updates can assume that there will be no synchronization
issues if the buffer is mapped into memory.
This converts the deferred lighting shader to use uniform buffers for
the dynamic data sent to the GPU while rendering the lighting effects.
This doesn't affect performance but the deferred lighting code is a
nicely isolated piece of rendering code where I could test how the
rendering code could use the uniform buffers.
This is related to #910.
asarium