defines and alters a series of material features for deferred shading in order to define a fully fleshed out multiple render target gbuffer patterned after the general principles outlined http://www.catalinzima.com/xna/tutorials/deferred-rendering-in-xna/creating-the-g-buffer/ (though I cannot stress enough *not* using the identical layout)
script:
removes dead material features (ie: those that never functioned to begin with)
shader:
bool getFlag(float flags, int num) definition for retreiving data from the 3rd (matinfo) gbuffer slot's red channel (more on that shortly)
purpose:
_A)_ Small primer on how material features function:
When a https://github.com/GarageGames/Torque3D/search?utf8=%E2%9C%93&q=_determineFeatures call is executed, certain conditions trigger a given .addFeature(MFT_SOMEFEATURE) call based upon material definition entries, be it a value, a texture reference, or even the presence or lack thereof for another feature. In general terms, the first to be executed is ProcessedShaderMaterial::_determineFeatures followed by ProcessedPrePassMaterial::_determineFeatures. The next commit will provide the bindings there. For now it's enough to understand that one of those two will trigger the shadergen subsystem, when rendering a material, to check it's associated list of features and spit out a shader if one is not already defined, or reference a pre-existing one that includes codelines determined by that list of features.
Relevant execution of this is as follows:
DeclareFeatureType( MFT_DeferredDiffuseMap ); - Name
ImplementFeatureType( MFT_DeferredDiffuseMap, MFG_Texture, 2.0f, false ); - Codeline Insertion Order
FEATUREMGR->registerFeature( MFT_DeferredDiffuseMap, new DeferredDiffuseMapHLSL ); - Hook to class which actually generates code
alternately FEATUREMGR->registerFeature( MFT_Imposter, new NamedFeatureHLSL( "Imposter" ) ); - a simple feature that serves no purpose further than as a test of it's existence (to modify other features for instance)
class DeferredDiffuseMapHLSL : public ShaderFeatureHLSL - Class definition
{
getName -embeded in the proceedural shader as a remline both up top and before actual code insertions
processPix - pixel shader codeline insertions
getOutputTargets - used to determine which buffer is written to (assumes only one. depending on branched logic, older features that may be run for either forward or deferred rendering depending on circumstance may have a logical switch based on additional feature flags. as an example: TerrainBaseMapFeatHLSL::getOutputTargets)
getResources - associated with the Resources struct, closely aligned with the hardware regestry
getBlendOp - used to determine what blend operation to use if a material requires a second pass (defaults to overwriting)
setTexData - ???
processVert - vertex shader codeline insertions
};
_B)_
The resultant Gbuffer layout defined by the previous commit therefore is as follows:
defaultrendertarget (referred to in shaders as out.col or col depending on GFX plugin) contains either lighting and normal data, or color data depending on if it is used in a deferred or forward lit manner (note for forward lit, this data is replaced as a second step with color. why custommaterials have traditionally had problems with lighting)
color1 (referred to in shaders as out.col1 or col1 depending on GFX plugin) RGB color data and an A for blending operations (including transparency)
color2 (referred to in shaders as out.col2 or col2 depending on GFX plugin) contains:
red channel comprising material flags such as metalness, emissive, ect,
green channel for translucency (light shining through, as oposed to see-through transparency), blue for
blue for specular strength (how much light influences net color)
alpha for specular power (generally how reflective/glossy an object is)
long term purpose:
further down the line, these will be used to condition data for use with a PBR subsystem, with further corrections to the underlying mathematics, strength being replaced by roughness, and power by metalness
Phase 1: buffers
engine:
provides the following hooks and methods
A) render target "color", and "matinfo". these correspond to texture[0] = "#color"; texture[2] = "#matinfo"; entries in scripts
B) utilizes the independentMrtBitDepth method added GarageGames#857 to set color to an 8RGBA if cards support it
C) adds an RenderPrePassMgr::_initShaders() method to support void RenderPrePassMgr::clearBuffers(). This operates as a pseudo-postfx by rendering a veiwspace plane which fills the screen, then calls a shader which fills both the introduced rendertarget buffers and the prepass buffer to relevant defaults (white with full alpha for prepass, black with full alpha for color and material respectively)
script:
\game\tools\worldEditor\main.cs adds additional hooks similar to GarageGames#863 for colorbuffer, specular map, and backbuffer display
\game\core\scripts\client\lighting\advanced\deferredShading.cs adds the clearbuffer shader, visualizers, and the ShaderData( AL_DeferredShader ) + PostEffect( AL_DeferredShading ) which combine the various buffers into the output which reaches the screen under normal conditions, as well as the extended debug visualizers.
again, note the lines
texture[0] = "#color";
texture[1] = "#lightinfo";
texture[2] = "#matinfo";
target = "$backBuffer";
in particular for the core tie-in.
shader:
\game\shaders\common\lighting\advanced\deferredColorShaderP.hlsl
\game\shaders\common\lighting\advanced\gl\deferredClearGBufferP.glsl
the previously mentioned shaders which clear the buffers to specified colors
\game\shaders\common\lighting\advanced\deferredShadingP.hlsl
\game\shaders\common\lighting\advanced\gl\deferredShadingP.glsl
the tie-in shaders
the rest are visualizers
purpose: to expose methodology that allows one to render color, lighting and material information such as specular and gloss which effect the result of both when combined
long term intent: the previous prepass lighting methodology while serviceable, unfortunately had the side effect of throwing out raw color information required by more modern pipelines and methodologies. This preserves that data while also allowing the manipulation to occur only on a screenspace (or reflected speudo-screenspace) basis.
Agreed, it makes sense that the shaders are common, so that people can start with empty and add their own art without worrying about stuff not working as expected.
SPECIAL NOTE: highly suggest https://github.com/GarageGames/Torque3D/pull/1441 or a variation thereof to prevent debug spew and false-postives for occlusion results.
With significant research, development and prototyping assistance from both @andr3wmac (shaders and partial hook work), and @LuisAntonRebollo (additional culling)
System operates as follows:
1) materials are given an additional castDynamicShadows boolean entry. (Default at time of writing is true by request. Personal usage at time of writing defaults to false. value is default-initialized in materialDefinition.cpp. script/gui exposed)
2) lights are given a staticRefreshFreq and dynamicRefreshFreq (in milliseconds). script/gui exposed
3) materials are (effectively) sorted into dynamic and static shadowmap render lists based on flag. (see shadowMapPass.cpp)
4) initial shadowmaps are generated for each light and 'list'.
5) as each refreshFreq times out, the relevant shadowmap for a given light is refreshed.
Special notes:
dynamicRefreshFreq for all lights is set to a (script exposed) 8MS refresh timer.
StaticRefreshFreq for the lions share of lights defaults to 250 MS (1/4 of a second)
scattersky's embedded light, which is intended to operate in a mobile manner, defaults to 8
to reiterate, these are all customizable per-light via script/inspector gui in the case of alternate project needs.
%distscale can actually end up negative. causes miscalculations for applyimpulse and the like (or even healing if you've hacked in the capacity for negative damage)
This resolves menu order, cleanup and close/re-open issues, as well as crashes on close.
It also modifies the look slightly to look closer to the windows menubar to keep a cohesive look regardless of platform.
