From 8ec8b16a88fad7c99de61e73480643450c30fa02 Mon Sep 17 00:00:00 2001
From: Lightling <contactlightling@gmail.com>
Date: Sat, 19 Mar 2022 17:39:52 -0400
Subject: [PATCH] support 3 directional lights

---
 DX11Starter.vcxproj    | 12 ++++++++++++
 Game.cpp               | 27 +++++++++++++++++++++------
 Game.h                 |  3 ++-
 SimplePixelShader.hlsl | 20 +++++++++++++++-----
 4 files changed, 50 insertions(+), 12 deletions(-)

diff --git a/DX11Starter.vcxproj b/DX11Starter.vcxproj
index bfb095b..9a57e96 100644
--- a/DX11Starter.vcxproj
+++ b/DX11Starter.vcxproj
@@ -80,6 +80,9 @@
     <Link>
       <SubSystem>Windows</SubSystem>
     </Link>
+    <FxCompile>
+      <ShaderModel>5.0</ShaderModel>
+    </FxCompile>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
     <ClCompile>
@@ -91,6 +94,9 @@
     <Link>
       <SubSystem>Windows</SubSystem>
     </Link>
+    <FxCompile>
+      <ShaderModel>5.0</ShaderModel>
+    </FxCompile>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <ClCompile>
@@ -106,6 +112,9 @@
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
     </Link>
+    <FxCompile>
+      <ShaderModel>5.0</ShaderModel>
+    </FxCompile>
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
     <ClCompile>
@@ -121,6 +130,9 @@
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
     </Link>
+    <FxCompile>
+      <ShaderModel>5.0</ShaderModel>
+    </FxCompile>
   </ItemDefinitionGroup>
   <ItemGroup>
     <ClCompile Include="Camera.cpp" />
diff --git a/Game.cpp b/Game.cpp
index ff5aed4..49c6853 100644
--- a/Game.cpp
+++ b/Game.cpp
@@ -98,11 +98,27 @@ void Game::LoadShaders()
 
 void Game::LoadLighting()
 {
-	directionalLight1 = {};
+	ambient = XMFLOAT3(0.05f, 0.05f, 0.20f);
+	Light directionalLight0 = {};
+	directionalLight0.Type = LIGHT_TYPE_DIRECTIONAL;
+	directionalLight0.Direction = XMFLOAT3(1, 0, 0);
+	directionalLight0.Color = XMFLOAT3(1, 0, 0);
+	directionalLight0.Intensity = 1;
+	Light directionalLight1 = {};
 	directionalLight1.Type = LIGHT_TYPE_DIRECTIONAL;
-	directionalLight1.Direction = XMFLOAT3(1, 0, 0);
-	directionalLight1.Color = XMFLOAT3(1.0f, 0, 0);
-	directionalLight1.Intensity = 1.0f;
+	directionalLight1.Direction = XMFLOAT3(0, -1, 0);
+	directionalLight1.Color = XMFLOAT3(0, 1, 0);
+	directionalLight1.Intensity = 1;
+	Light directionalLight2 = {};
+	directionalLight2.Type = LIGHT_TYPE_DIRECTIONAL;
+	directionalLight2.Direction = XMFLOAT3(-1, 1, -0.5f);
+	directionalLight2.Color = XMFLOAT3(0, 0, 1);
+	directionalLight2.Intensity = 1;
+	lights = {
+		directionalLight0,
+		directionalLight1,
+		directionalLight2,
+	};
 }
 
 // --------------------------------------------------------
@@ -190,7 +206,6 @@ void Game::Draw(float deltaTime, float totalTime)
 {
 	// Background color (Cornflower Blue in this case) for clearing
 	static const float color[4] = { 0.4f, 0.6f, 0.75f, 0.0f };
-	static const DirectX::XMFLOAT3 ambient = XMFLOAT3(0.1f, 0.1f, 0.25f);
 
 	// Clear the render target and depth buffer (erases what's on the screen)
 	//  - Do this ONCE PER FRAME
@@ -216,7 +231,7 @@ void Game::Draw(float deltaTime, float totalTime)
 		ps->SetFloat("roughness", entity->GetMaterial()->GetRoughness());
 		ps->SetFloat3("tint", entity->GetMaterial()->GetTint());
 		ps->SetFloat3("ambient", ambient);
-		ps->SetData("directionalLight1", &directionalLight1, sizeof(Light));
+		ps->SetData("lights", &lights[0], sizeof(Light) * (int)lights.size());
 		ps->CopyAllBufferData();
 
 		entity->GetMaterial()->GetVertexShader()->SetShader();
diff --git a/Game.h b/Game.h
index 5c5b510..7a58050 100644
--- a/Game.h
+++ b/Game.h
@@ -55,7 +55,8 @@ private:
 	// A6 Materials
 	std::vector<std::shared_ptr<Material>> materials;
 	// A7 Lights
-	Light directionalLight1;
+	std::vector<Light> lights;
+	DirectX::XMFLOAT3 ambient;
 
 	Microsoft::WRL::ComPtr<ID3D11Buffer> constantBufferVS;
 };
diff --git a/SimplePixelShader.hlsl b/SimplePixelShader.hlsl
index f95df1a..d986fcb 100644
--- a/SimplePixelShader.hlsl
+++ b/SimplePixelShader.hlsl
@@ -2,13 +2,16 @@
 #include "Helpers.hlsli"
 #include "Lights.hlsli"
 
+// temporary
+#define LIGHT_COUNT 3
+
 cbuffer ExternalData : register(b0)
 {
 	float3 cameraPosition;
 	float roughness;
 	float3 ambient;
 	float3 tint;
-	Light directionalLight1;
+	Light lights[LIGHT_COUNT];
 }
 
 float calculateSpecular(float3 normal, float3 direction, float3 worldPosition, float3 cameraPosition, float roughness)
@@ -33,9 +36,16 @@ float4 main(VertexToPixel input) : SV_TARGET
 {
 	input.normal = normalize(input.normal);
 
-	float3 light = calculateDirectionalLight(directionalLight1, input.normal, input.worldPosition, cameraPosition, roughness, tint);
-	float3 ambientTint = ambient * tint;
-	float3 final = light + ambientTint;
+	float3 light = ambient * tint;
+	for (int i = 0; i < LIGHT_COUNT; i++)
+	{
+		switch (lights[i].Type)
+		{
+		case LIGHT_TYPE_DIRECTIONAL:
+			light += calculateDirectionalLight(lights[i], input.normal, input.worldPosition, cameraPosition, roughness, tint);
+			break;
+		}
+	}
 
-	return float4(final, 1);
+	return float4(light, 1);
 }