Hah this took a while, as there was no texture scaffolding in place at
all. Thus all this had to be added and tested for the first time:
* 2D textures
* 2D texture arrays
* Texture transformation uniforms
* Texture transformation UBOs
* Instanced texture offset
This also means that MeshVisualizer can be used to visualize arbitrary
(single-channel) integer textures now, not just render meshes with
object ID textures. Yay for feature parity!
Mainly to have feature parity with Flat and Phong -- otherwise switching
to draw a wireframe on an instanced mesh would be too annoying. Also, if
we have multidraw there already, why not instancing as well.
Originally the uniform wasn't present with the assumption that users
could easily adjust color map offset to achieve the same effect. That
was however unnecessarily annoying and error-prone in cases where it's
essential to have the same object IDs from multiple draws have a
matching color, and it was complicating multidraw workflows as the color
map offset was not a part of per-draw data, but rather material data.
This is always true in the single-draw case, since setDrawOffset()
asserts on this. In the multi-draw case this optimization doesn't make
sense, because it doesn't make sense to create a multidraw shader with
just one draw.
On an Intel 630 GPU this resulted in single-draw single-material Phong
to go from 550 ms to 440, which is roughly a 20% improvement. For the
simpler shaders the difference is even higher. The multidraw numbers
stayed the same as before, obviously.
WebGL mandates that array subscription is done with constant expression,
ANGLE too (but I think that has also something to do with D3D9
limitations). This is however allowed by OpenGL ES 2.0 specification, so
enabling the workaround only for WebGL and ANGLE (i.e., this won't apply
to Native Client using native GL drivers).
Everything what was in src/ is now in src/Corrade, everything from
src/Plugins is now in src/MagnumPlugins, everything from external/ is in
src/MagnumExternal. Added new CMakeLists.txt file and updated the other
ones for the moves, no other change was made. If MAGNUM_BUILD_DEPRECATED
is set, everything compiles and installs like previously except for the
plugins, which are now in MagnumPlugins and not in Magnum/Plugins.
Rudely written to work only with fairly recent extensions and nothing
less than GLSL 3.30. It requires geometry shaders for wireframe
rendering, without it it behaves the same as Shaders::Flat.