add a skeletal animation sample using ozz-animation library

.gitmodules

@@ -4,3 +4,6 @@
 [submodule "ThirdParty/glfw"]
 	path = ThirdParty/glfw
 	url = https://github.com/DiligentGraphics/glfw.git
+[submodule "ThirdParty/ozz-animation"]
+	path = ThirdParty/ozz-animation
+	url = https://github.com/guillaumeblanc/ozz-animation.git

Samples/Animation/Animation00_Playback/CMakeLists.txt

@@ -0,0 +1,35 @@
+cmake_minimum_required (VERSION 3.6)
+
+project(Animation00_Playback CXX)
+
+set(SOURCE
+    src/Animation00_Playback.cpp
+    ../Common/src/AnimationUtilities.cpp
+    ../Common/src/PlaybackController.cpp
+)
+
+set(INCLUDE
+    src/Animation00_Playback.hpp
+    ../Common/src/AnimationUtilities.hpp
+    ../Common/src/PlaybackController.hpp
+)
+
+set(SHADERS
+    assets/skeleton.vsh
+    assets/skeleton.psh
+    assets/plane.vsh
+    assets/plane.psh    
+)
+
+set(ASSETS
+    assets/pab_crossarms.ozz
+    assets/pab_skeleton.ozz
+)
+
+add_sample_app("Animation00_Playback" "DiligentSamples/Samples/Animation" "${SOURCE}" "${INCLUDE}" "${SHADERS}" "${ASSETS}")
+
+target_link_libraries(Animation00_Playback
+PRIVATE
+    ozz_base
+    ozz_animation
+)

Samples/Animation/Animation00_Playback/assets/plane.psh

@@ -0,0 +1,32 @@
+struct PlanePSInput
+{
+    float4 Pos : SV_POSITION;
+    float2 TexCoord : TEXCOORD;
+};
+
+struct PlanePSOutput
+{
+    float4 Color : SV_TARGET;
+};
+
+void main(in  PlanePSInput  PSIn,
+          out PlanePSOutput PSOut)
+{
+    float tol = 0.001000000;
+    float res = 0.05;
+    float4 backgroundColor = float4(0.5, 0.75, 0.85, 1.0f); // blue
+    float4 lineColor       = float4(0.25, 0.25, 0.25, 1.0); // grey
+    float4 originColor     = float4(0.0, 0.0, 0.0, 1.0);   // black
+    if (((abs(((PSIn.TexCoord).x - 0.5)) <= tol) && (abs(((PSIn.TexCoord).y - 0.5)) <= tol)))
+    {
+        PSOut.Color = originColor;
+    }
+    else if (((((fmod((PSIn.TexCoord).x, res) >= (res - tol)) || (fmod((PSIn.TexCoord).x, res) < tol)) || (fmod((PSIn.TexCoord).y, res) >= (res - tol))) || (fmod((PSIn.TexCoord).y, res) < tol)))
+    {
+        PSOut.Color = lineColor;
+    }
+    else
+    {
+        PSOut.Color = backgroundColor;
+    }
+}

Samples/Animation/Animation00_Playback/assets/plane.vsh

@@ -0,0 +1,32 @@
+cbuffer Constants
+{
+    float4x4 g_WorldViewProj;
+}
+
+struct PlanePSInput
+{
+    float4 Pos : SV_POSITION;
+    float2 TexCoord : TEXCOORD;
+};
+
+void main(in  uint    VertId : SV_VertexID,
+          out PlanePSInput PSIn)
+{
+    float PlaneExtent = 5.0;
+    float PlanePos    = 0.0;
+
+    float4 Pos[4];
+    Pos[0] = float4(-PlaneExtent, PlanePos, -PlaneExtent, 1.0);
+    Pos[1] = float4(-PlaneExtent, PlanePos, +PlaneExtent, 1.0);
+    Pos[2] = float4(+PlaneExtent, PlanePos, -PlaneExtent, 1.0);
+    Pos[3] = float4(+PlaneExtent, PlanePos, +PlaneExtent, 1.0);
+
+    float2 Uv[4];
+    Uv[0] = float2(0.0, 0.0);
+    Uv[1] = float2(0.0, 1.0);
+    Uv[2] = float2(1.0, 0.0);
+    Uv[3] = float2(1.0, 1.0);
+
+    PSIn.Pos = mul(Pos[VertId], g_WorldViewProj);
+    PSIn.TexCoord = Uv[VertId];
+}

Samples/Animation/Animation00_Playback/assets/skeleton.psh

@@ -0,0 +1,31 @@
+struct PSInput 
+{ 
+    float4 Pos   : SV_POSITION; 
+    float3 Normal : NORMAL; 
+    float4 Color : COLOR0; 
+};
+
+struct PSOutput
+{ 
+    float4 Color : SV_TARGET; 
+};
+
+float4 GetAmbient(float3 WorldNormal)
+{
+    float3 Normal = normalize(WorldNormal);
+    float3 Alpha = (Normal + 1.0) * 0.5;
+    float2 Bt = lerp(float2(0.3, 0.7), float2(0.4, 0.8), Alpha.xz);
+    float3 Ambine = lerp(float3(Bt.x, 0.3, Bt.x), float3(Bt.y, 0.8, Bt.y), Alpha.y);
+
+    return float4(Ambine, 1.0);
+}
+
+// Note that if separate shader objects are not supported (this is only the case for old GLES3.0 devices), vertex
+// shader output variable name must match exactly the name of the pixel shader input variable.
+// If the variable has structure type (like in this example), the structure declarations must also be indentical.
+void main(in  PSInput  PSIn,
+          out PSOutput PSOut)
+{
+    float4 Ambine = GetAmbient(PSIn.Normal);
+    PSOut.Color   = Ambine * PSIn.Color;
+}

Samples/Animation/Animation00_Playback/assets/skeleton.vsh

@@ -0,0 +1,53 @@
+cbuffer Constants
+{
+    float4x4 g_WorldViewProj;
+};
+
+// Vertex shader takes two inputs: vertex position and color.
+// By convention, Diligent Engine expects vertex shader inputs to be 
+// labeled 'ATTRIBn', where n is the attribute number.
+struct VSInput
+{
+    // Vertex attributes
+    float3 Pos   :  ATTRIB0;
+    float3 Normal : ATTRIB1;
+    float4 Color :  ATTRIB2;
+
+    // Instance attributes
+    float4 MtrxRow0 : ATTRIB3;
+    float4 MtrxRow1 : ATTRIB4;
+    float4 MtrxRow2 : ATTRIB5;
+    float4 MtrxRow3 : ATTRIB6;
+};
+
+struct PSInput 
+{ 
+    float4 Pos   : SV_POSITION; 
+    float3 Normal : NORMAL; 
+    float4 Color : COLOR0; 
+};
+
+// Note that if separate shader objects are not supported (this is only the case for old GLES3.0 devices), vertex
+// shader output variable name must match exactly the name of the pixel shader input variable.
+// If the variable has structure type (like in this example), the structure declarations must also be indentical.
+void main(in  VSInput VSIn,
+          out PSInput PSIn) 
+{
+    // HLSL matrices are row-major while GLSL matrices are column-major. We will
+    // use convenience function MatrixFromRows() appropriately defined by the engine
+    float4x4 InstanceMatr = MatrixFromRows(VSIn.MtrxRow0, VSIn.MtrxRow1, VSIn.MtrxRow2, VSIn.MtrxRow3);
+    // Apply instance-specific transformation
+    float4 TransformedPos = mul(float4(VSIn.Pos, 1.0), InstanceMatr);
+    // Apply view-projection matrix
+    PSIn.Pos = mul(TransformedPos, g_WorldViewProj);
+
+    float3x3 CrossMatr = float3x3(
+        cross(InstanceMatr[1].xyz, InstanceMatr[2].xyz),
+        cross(InstanceMatr[2].xyz, InstanceMatr[0].xyz),
+        cross(InstanceMatr[0].xyz, InstanceMatr[1].xyz)
+    );
+    float    Invdet     = 1.0 / dot(CrossMatr[2], InstanceMatr[2].xyz);
+    float3x3 NormalMatr = CrossMatr * Invdet;
+    PSIn.Normal         = mul(VSIn.Normal, NormalMatr);
+    PSIn.Color = VSIn.Color;
+}

Samples/Animation/Animation00_Playback/readme.md

@@ -0,0 +1,5 @@
+# Animation Playback Demo
+
+![](Screenshot.png)
+
+This sample demonstrates how to integrate ozz-animation library into an application to play skeletal animation.