From f346e55819777fb3987801a980d624692676aafb Mon Sep 17 00:00:00 2001
From: Vladislav Khorev <mephi1984@gmail.com>
Date: Mon, 10 Jun 2024 22:18:06 +0300
Subject: [PATCH] Now bump mapping works

---
 include/Render/RenderMisc.h       |  6 +++
 src/ModelManager/ModelManager.cpp | 11 +++--
 src/Render/RenderMisc.cpp         | 78 +++++++++++++++++++++++++++++++
 3 files changed, 92 insertions(+), 3 deletions(-)

diff --git a/include/Render/RenderMisc.h b/include/Render/RenderMisc.h
index 402672b..e74a8ec 100644
--- a/include/Render/RenderMisc.h
+++ b/include/Render/RenderMisc.h
@@ -55,12 +55,18 @@ namespace SE
 		std::vector<vec3> PositionData;
 		std::vector<vec2> TexCoordData;
 		std::vector<vec3> NormalData;
+		std::vector<vec3> TangentData;
+		std::vector<vec3> BitangentData;
 
 		std::shared_ptr<VAOHolder> vao;
 		std::shared_ptr<VBOHolder> positionVBO;
 		std::shared_ptr<VBOHolder> texCoordVBO;
 		std::shared_ptr<VBOHolder> normalVBO;
+		std::shared_ptr<VBOHolder> tangentVBO;
+		std::shared_ptr<VBOHolder> bitangentVBO;
 		void RefreshVBO();
+
+		void CalcTangentBitangent();
 	};
 
 struct T2DQuad
diff --git a/src/ModelManager/ModelManager.cpp b/src/ModelManager/ModelManager.cpp
index df605cd..53dbf12 100644
--- a/src/ModelManager/ModelManager.cpp
+++ b/src/ModelManager/ModelManager.cpp
@@ -121,6 +121,8 @@ bool TLiteModel::LoadModel(const std::string& s)
 	vertexDataStruct.TexCoordData = res.TexCoordArr;
 	vertexDataStruct.NormalData = res.NormalArr;
 
+	vertexDataStruct.CalcTangentBitangent();
+
 	vertexDataStruct.RefreshVBO();
 	/*
 	TriangleList.Data.Vec3CoordArr[CONST_STRING_POSITION_ATTRIB] = res.VertexArr;
@@ -239,11 +241,14 @@ void TLiteModel::DrawVBO()
 	EnableVertexAttribArray("vPosition");
 	EnableVertexAttribArray("vTexCoord");
 	EnableVertexAttribArray("vNormal");
-
+	EnableVertexAttribArray("vTangent");
+	EnableVertexAttribArray("vBitangent");
 
 	//Renderer->DrawTriangleList(TriangleList);
 	DrawVertexDataStruct(vertexDataStruct);
 
+	DisableVertexAttribArray("vBitangent");
+	DisableVertexAttribArray("vTangent");
 	DisableVertexAttribArray("vNormal");
 	DisableVertexAttribArray("vTexCoord");
 	DisableVertexAttribArray("vPosition");
@@ -256,8 +261,6 @@ void TLiteModel::DrawVBO()
 }
 
 
-
-
 void TLiteModel::MoveModel(const vec3& v)
 {
 	for (cardinal i = 0; i < TriangleCount * 3; i++)
@@ -274,6 +277,8 @@ void TLiteModel::RotateModel(const mat3& r)
 	{
 		vertexDataStruct.PositionData[i] = r * vertexDataStruct.PositionData[i];
 		vertexDataStruct.NormalData[i] = r * vertexDataStruct.NormalData[i];
+		vertexDataStruct.TangentData[i] = r * vertexDataStruct.TangentData[i];
+		vertexDataStruct.BitangentData[i] = r * vertexDataStruct.BitangentData[i];
 		//TriangleList.Data.Vec3CoordArr[CONST_STRING_POSITION_ATTRIB][i] = r * TriangleList.Data.Vec3CoordArr[CONST_STRING_POSITION_ATTRIB][i];
 		//TriangleList.Data.Vec3CoordArr[CONST_STRING_NORMAL_ATTRIB][i] = r * TriangleList.Data.Vec3CoordArr[CONST_STRING_NORMAL_ATTRIB][i];
 		//TriangleList.Data.Vec3CoordArr[CONST_STRING_TANGENT_ATTRIB][i] = r * TriangleList.Data.Vec3CoordArr[CONST_STRING_TANGENT_ATTRIB][i];
diff --git a/src/Render/RenderMisc.cpp b/src/Render/RenderMisc.cpp
index cfda087..9758cca 100644
--- a/src/Render/RenderMisc.cpp
+++ b/src/Render/RenderMisc.cpp
@@ -79,6 +79,70 @@ namespace SE
 
 		}
 
+		if (TangentData.size() > 0)
+		{
+			if (!tangentVBO)
+			{
+				tangentVBO = std::make_shared<VBOHolder>();
+			}
+
+			glBindBuffer(GL_ARRAY_BUFFER, tangentVBO->getBuffer());
+
+			glBufferData(GL_ARRAY_BUFFER, TangentData.size() * 12, &TangentData[0], GL_STATIC_DRAW);
+
+		}
+
+		if (BitangentData.size() > 0)
+		{
+			if (!bitangentVBO)
+			{
+				bitangentVBO = std::make_shared<VBOHolder>();
+			}
+
+			glBindBuffer(GL_ARRAY_BUFFER, bitangentVBO->getBuffer());
+
+			glBufferData(GL_ARRAY_BUFFER, BitangentData.size() * 12, &BitangentData[0], GL_STATIC_DRAW);
+
+		}
+
+	}
+
+	void VertexDataStruct::CalcTangentBitangent()
+	{
+		TangentData.clear();
+		BitangentData.clear();
+
+		for (int i = 0; i < PositionData.size() / 3; i++)
+		{
+			vec3 v0 = PositionData[i * 3];
+			vec3 v1 = PositionData[i * 3 + 1];
+			vec3 v2 = PositionData[i * 3 + 2];
+
+			vec2 t0 = TexCoordData[i * 3];
+			vec2 t1 = TexCoordData[i * 3 + 1];
+			vec2 t2 = TexCoordData[i * 3 + 2];
+
+			vec3 deltaPos1 = v1 - v0;
+			vec3 deltaPos2 = v2 - v0;
+			vec2 deltaUV1 = t1 - t0;
+			vec2 deltaUV2 = t2 - t0;
+
+			float r = 1.0f / (deltaUV1.v[0] * deltaUV2.v[1] - deltaUV1.v[1] * deltaUV2.v[0]);
+
+			vec3 tangent = (deltaPos1 * deltaUV2.v[1] - deltaPos2 * deltaUV1.v[1]) * r;
+			vec3 bitangent = (deltaPos2 * deltaUV1.v[0] - deltaPos1 * deltaUV2.v[0]) * r;
+
+			TangentData.push_back(tangent);
+			TangentData.push_back(tangent);
+			TangentData.push_back(tangent);
+
+			BitangentData.push_back(bitangent);
+			BitangentData.push_back(bitangent);
+			BitangentData.push_back(bitangent);
+
+		}
+
+		RefreshVBO();
 	}
 
 	void DrawVertexDataStruct(const VertexDataStruct& vertexDataStruct)
@@ -86,6 +150,8 @@ namespace SE
 		static const std::string vTexCoord("vTexCoord");
 		static const std::string vPosition("vPosition");
 		static const std::string vNormal("vNormal");
+		static const std::string vTangent("vTangent");
+		static const std::string vBitangent("vBitangent");
 
 		//Check if main thread, check if data is not empty...
 		glBindBuffer(GL_ARRAY_BUFFER, vertexDataStruct.texCoordVBO->getBuffer());
@@ -97,6 +163,18 @@ namespace SE
 			VertexAttribPointer3fv(vNormal, 0, NULL);
 		}
 
+		if (vertexDataStruct.tangentVBO)
+		{
+			glBindBuffer(GL_ARRAY_BUFFER, vertexDataStruct.tangentVBO->getBuffer());
+			VertexAttribPointer3fv(vTangent, 0, NULL);
+		}
+
+		if (vertexDataStruct.bitangentVBO)
+		{
+			glBindBuffer(GL_ARRAY_BUFFER, vertexDataStruct.bitangentVBO->getBuffer());
+			VertexAttribPointer3fv(vBitangent, 0, NULL);
+		}
+
 		glBindBuffer(GL_ARRAY_BUFFER, vertexDataStruct.positionVBO->getBuffer());
 		VertexAttribPointer3fv(vPosition, 0, NULL);