From b4dd3be584e886af4190bf7992befe0798ff27c3 Mon Sep 17 00:00:00 2001
From: EmaMaker <emamaker0@gmail.com>
Date: Sun, 26 Mar 2023 19:57:39 +0200
Subject: [PATCH] chunkmesher: push vertices normals to GPU

---
 include/chunkmesher.hpp |  3 ++-
 shaders/shader.fs       |  4 +++-
 shaders/shader.vs       |  9 +++++++--
 src/chunkmesher.cpp     | 34 ++++++++++++++++++++++++++++------
 4 files changed, 40 insertions(+), 10 deletions(-)

diff --git a/include/chunkmesher.hpp b/include/chunkmesher.hpp
index 3f985e9..5f50b98 100644
--- a/include/chunkmesher.hpp
+++ b/include/chunkmesher.hpp
@@ -16,7 +16,8 @@ namespace chunkmesher{
     void sendtogpu(Chunk::Chunk* chunk);
     void draw(Chunk::Chunk* chunk, glm::mat4 model);
 
-    void quad(Chunk::Chunk* chunk, glm::vec3 bottomLeft, glm::vec3 topLeft, glm::vec3 topRight, glm::vec3 bottomRight, Block block, bool backFace);
+    void quad(Chunk::Chunk* chunk, glm::vec3 bottomLeft, glm::vec3 topLeft, glm::vec3 topRight,
+	    glm::vec3 bottomRight, glm::vec3 normal, Block block, bool backFace);
 }
 
 
diff --git a/shaders/shader.fs b/shaders/shader.fs
index 8e6a06a..6b13a29 100644
--- a/shaders/shader.fs
+++ b/shaders/shader.fs
@@ -1,10 +1,12 @@
 #version 330 core
 
 in vec4 vColor;
+in vec3 vNormal;
+
 out vec4 FragColor;
 
 void main()
 {
     FragColor = vColor;
     // FragColor=  vec4(1.0f, 1.0f, 1.0f, 1.0f);
-}
\ No newline at end of file
+}
diff --git a/shaders/shader.vs b/shaders/shader.vs
index af49fa5..ae918f5 100644
--- a/shaders/shader.vs
+++ b/shaders/shader.vs
@@ -1,15 +1,20 @@
 #version 330 core
+
 layout (location = 0) in vec3 aPos;
-layout (location = 1) in vec3 aColor;
+layout (location = 1) in vec3 aNormal;
+layout (location = 2) in vec3 aColor;
 
 uniform mat4 model;
 uniform mat4 view;
 uniform mat4 projection;
 
 out vec4 vColor;
+out vec3 vNormal;
 
 void main()
 {
     vColor = vec4(aColor, 1.0f);
+    vNormal = aNormal;
+
     gl_Position = projection * view * model * vec4(aPos, 1.0);
-}
\ No newline at end of file
+}
diff --git a/src/chunkmesher.cpp b/src/chunkmesher.cpp
index 800bf1e..623fab2 100755
--- a/src/chunkmesher.cpp
+++ b/src/chunkmesher.cpp
@@ -151,6 +151,7 @@ void mesh(Chunk::Chunk* chunk)
                                      glm::vec3(x[0] + du[0] + dv[0], x[1] + du[1] + dv[1],
                                                x[2] + du[2] + dv[2]),
                                      glm::vec3(x[0] + dv[0], x[1] + dv[1], x[2] + dv[2]),
+				     glm::vec3(backFace ? q[0] : -q[0], backFace ? q[1] : -q[1], backFace ? q[2] : -q[2] ),
                                      mask[n], backFace);
                             }
 
@@ -192,17 +193,24 @@ void sendtogpu(Chunk::Chunk* chunk)
 	glBindBuffer(GL_ARRAY_BUFFER, chunk->VBO);
 	glBufferData(GL_ARRAY_BUFFER, chunk->vertices.size() * sizeof(GLfloat), &(chunk->vertices[0]), GL_STATIC_DRAW);
 
+	// position attribute
+	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void *)0);
+	glEnableVertexAttribArray(0);
+
+	// normal attribute
+	glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void *)(3*
+		    sizeof(float)));
+	glEnableVertexAttribArray(1);
+
 	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, chunk->EBO);
 	glBufferData(GL_ELEMENT_ARRAY_BUFFER, chunk->indices.size() * sizeof(GLuint), &(chunk->indices[0]), GL_STATIC_DRAW);
 
-	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void *)0);
-	glEnableVertexAttribArray(0);
-
+	// color attribute
 	glBindBuffer(GL_ARRAY_BUFFER, chunk->colorBuffer);
 	glBufferData(GL_ARRAY_BUFFER, chunk->colors.size() * sizeof(GLfloat), &(chunk->colors[0]), GL_STATIC_DRAW);
 
-	glEnableVertexAttribArray(1);
-	glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void *)0);
+	glEnableVertexAttribArray(2);
+	glVertexAttribPointer(2, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void *)0);
 
 	glBindVertexArray(0);
 
@@ -236,24 +244,38 @@ void draw(Chunk::Chunk* chunk, glm::mat4 model)
     }
 }
 
-void quad(Chunk::Chunk* chunk, glm::vec3 bottomLeft, glm::vec3 topLeft, glm::vec3 topRight, glm::vec3 bottomRight, Block block, bool backFace)
+void quad(Chunk::Chunk* chunk, glm::vec3 bottomLeft, glm::vec3 topLeft, glm::vec3 topRight,
+	glm::vec3 bottomRight, glm::vec3 normal, Block block, bool backFace)
 {
 
     chunk->vertices.push_back(bottomLeft.x);
     chunk->vertices.push_back(bottomLeft.y);
     chunk->vertices.push_back(bottomLeft.z);
+    chunk->vertices.push_back(normal.x);
+    chunk->vertices.push_back(normal.y);
+    chunk->vertices.push_back(normal.z);
 
     chunk->vertices.push_back(bottomRight.x);
     chunk->vertices.push_back(bottomRight.y);
     chunk->vertices.push_back(bottomRight.z);
+    chunk->vertices.push_back(normal.x);
+    chunk->vertices.push_back(normal.y);
+    chunk->vertices.push_back(normal.z);
 
     chunk->vertices.push_back(topLeft.x);
     chunk->vertices.push_back(topLeft.y);
     chunk->vertices.push_back(topLeft.z);
+    chunk->vertices.push_back(normal.x);
+    chunk->vertices.push_back(normal.y);
+    chunk->vertices.push_back(normal.z);
 
     chunk->vertices.push_back(topRight.x);
     chunk->vertices.push_back(topRight.y);
     chunk->vertices.push_back(topRight.z);
+    chunk->vertices.push_back(normal.x);
+    chunk->vertices.push_back(normal.y);
+    chunk->vertices.push_back(normal.z);
+
 
     if (backFace)
     {