Implemented basic normal-dot product shading, preparing for more complex methods such as Blinn-Phong and PBR

assets/models/UVSphere.mtl

@@ -0,0 +1,2 @@
+# Blender 4.2.3 LTS MTL File: 'None'
+# www.blender.org

assets/models/untitled.mtl

@@ -1,12 +1,2 @@
 # Blender 4.2.3 LTS MTL File: 'None'
 # www.blender.org
-
-newmtl Material
-Ns 250.000000
-Ka 1.000000 1.000000 1.000000
-Ks 0.500000 0.500000 0.500000
-Ke 0.000000 0.000000 0.000000
-Ni 1.450000
-d 1.000000
-illum 2
-map_Kd /home/lillian/Downloads/d41777258e68c9d7046fc03c4d1d1e89.png

assets/models/untitled.obj

@@ -0,0 +1,39 @@
+# Blender 4.2.3 LTS
+# www.blender.org
+mtllib untitled.mtl
+o Cube
+v -6.996062 0.060240 6.002291
+v -6.996062 0.123414 6.002291
+v -6.996062 0.060240 -6.002291
+v -6.996062 0.123414 -6.002291
+v 6.996062 0.060240 6.002291
+v 6.996062 0.123414 6.002291
+v 6.996062 0.060240 -6.002291
+v 6.996062 0.123414 -6.002291
+vn -1.0000 -0.0000 -0.0000
+vn -0.0000 -0.0000 -1.0000
+vn 1.0000 -0.0000 -0.0000
+vn -0.0000 -0.0000 1.0000
+vn -0.0000 -1.0000 -0.0000
+vn -0.0000 1.0000 -0.0000
+vt 0.561014 0.000000
+vt 0.625000 0.000000
+vt 0.625000 0.250000
+vt 0.561014 0.250000
+vt 0.625000 0.500000
+vt 0.561014 0.500000
+vt 0.625000 0.750000
+vt 0.561014 0.750000
+vt 0.625000 1.000000
+vt 0.561014 1.000000
+vt 0.125000 0.500000
+vt 0.125000 0.750000
+vt 0.875000 0.500000
+vt 0.875000 0.750000
+s 0
+f 1/1/1 2/2/1 4/3/1 3/4/1
+f 3/4/2 4/3/2 8/5/2 7/6/2
+f 7/6/3 8/5/3 6/7/3 5/8/3
+f 5/8/4 6/7/4 2/9/4 1/10/4
+f 3/11/5 7/6/5 5/8/5 1/12/5
+f 8/5/6 4/13/6 2/14/6 6/7/6

imgui.ini

@@ -3,6 +3,6 @@ Pos=60,60
 Size=400,400
 
 [Window][Agnosia Debug]
-Pos=59,322
+Pos=57,392
 Size=623,438
 

src/agnosiaimgui.cpp

@@ -23,8 +23,8 @@ void initImGuiWindow() {
   }
 
   ImGui::DragFloat3("Camera Position", Graphics::getCamPos());
+  ImGui::DragFloat3("Light Position", Graphics::getLightPos());
   ImGui::DragFloat3("Center Position", Graphics::getCenterPos());
-  ImGui::DragFloat3("Up Direction", Graphics::getUpDir());
   ImGui::DragFloat("Depth of Field", &Graphics::getDepthField(), 0.1f, 1.0f,
                    180.0f, NULL, ImGuiSliderFlags_AlwaysClamp);
   ImGui::DragFloat2("Near and Far fields", Graphics::getDistanceField());

src/entrypoint.cpp

@@ -88,15 +88,15 @@ void createInstance() {
   }
 }
 void initAgnosia() {
-  Material *vikingRoomMaterial =
-      new Material("vikingRoomMaterial", "assets/textures/viking_room.png");
+  Material *sphereMaterial =
+      new Material("sphereMaterial", "assets/textures/checkermap.png");
   Material *stanfordDragonMaterial =
       new Material("stanfordDragonMaterial", "assets/textures/checkermap.png");
   Material *teapotMaterial =
       new Material("teapotMaterial", "assets/textures/checkermap.png");
-  Model *vikingRoom =
-      new Model("vikingRoom", *vikingRoomMaterial,
-                "assets/models/viking_room.obj", glm::vec3(0.0f, 0.0f, 0.0f));
+  Model *uvSphere =
+      new Model("uvSphere", *sphereMaterial, "assets/models/UVSphere.obj",
+                glm::vec3(0.0f, 0.0f, 0.0f));
   Model *stanfordDragon = new Model("stanfordDragon", *stanfordDragonMaterial,
                                     "assets/models/StanfordDragon800k.obj",
                                     glm::vec3(0.0f, 2.0f, 0.0f));

src/graphics/graphicspipeline.cpp

@@ -13,6 +13,7 @@
 #include <iostream>
 #include <vulkan/vulkan_core.h>
 
+float lightPos[4] = {5.0f, 5.0f, 5.0f, 0.44f};
 float camPos[4] = {3.0f, 3.0f, 3.0f, 0.44f};
 float centerPos[4] = {0.0f, 0.0f, 0.0f, 0.44f};
 float upDir[4] = {0.0f, 0.0f, 1.0f, 0.44f};
@@ -363,6 +364,7 @@ void Graphics::recordCommandBuffer(VkCommandBuffer commandBuffer,
     Agnosia_T::GPUPushConstants pushConsts;
     pushConsts.vertexBuffer = model->getBuffers().vertexBufferAddress;
     pushConsts.objPosition = model->getPos();
+    pushConsts.lightPos = glm::vec3(lightPos[0], lightPos[1], lightPos[2]);
     pushConsts.textureID = texID;
 
     pushConsts.model =
@@ -433,6 +435,7 @@ void Graphics::recordCommandBuffer(VkCommandBuffer commandBuffer,
 }
 
 float *Graphics::getCamPos() { return camPos; }
+float *Graphics::getLightPos() { return lightPos; }
 float *Graphics::getCenterPos() { return centerPos; }
 float *Graphics::getUpDir() { return upDir; }
 float &Graphics::getDepthField() { return depthField; }

src/graphics/graphicspipeline.h

@@ -15,6 +15,7 @@ public:
                                   uint32_t imageIndex);
 
   static float *getCamPos();
+  static float *getLightPos();
   static float *getCenterPos();
   static float *getUpDir();
   static float &getDepthField();

src/shaders/common.glsl

@@ -15,6 +15,7 @@ layout(buffer_reference, scalar) readonly buffer VertexBuffer{
 layout( push_constant, scalar ) uniform constants {
     VertexBuffer vertBuffer;
     vec3 objPos;
+    vec3 lightPos;
     int textureID;
     mat4 model;
     mat4 view;

src/shaders/fragment.frag

@@ -5,11 +5,18 @@
 layout(binding = 1) uniform sampler2D texSampler[];
 
 
-layout(location = 0) in vec3 fragColor;
-layout(location = 1) in vec2 fragTexCoord;
+layout(location = 0) in vec3 v_norm;
+layout(location = 1) in vec3 v_pos;
+layout(location = 2) in vec2 texCoord;
 
 layout(location = 0) out vec4 outColor;
 
 void main() {
-  outColor = texture(texSampler[PushConstants.textureID], fragTexCoord) * vec4(fragColor, 1.0f);
+  vec3 diffuseColor = texture(texSampler[PushConstants.textureID], texCoord).rgb;
+  vec3 ambientColor = vec3(0.05f,0.05f, 0.05f) * diffuseColor;
+  float lightPower = 5;
+  vec3 lightColor = vec3(1.0f, 1.0f, 1.0f);
+  float cosTheta = dot(PushConstants.lightPos, v_norm);
+  float sqrDist = distance(v_pos, PushConstants.lightPos)*distance(v_pos, PushConstants.lightPos);
+  outColor = vec4(ambientColor + clamp(diffuseColor * lightColor * lightPower * cosTheta / sqrDist, vec3(0,0,0), vec3(1,1,1)), 1.0f);
 }

src/shaders/vertex.vert

@@ -2,14 +2,16 @@
 #extension GL_GOOGLE_include_directive : enable
 #include "common.glsl"
 
-layout(location = 0) out vec3 fragColor;
-layout(location = 1) out vec2 fragTexCoord;
+layout(location = 0) out vec3 v_norm;
+layout(location = 1) out vec3 v_pos;
+layout(location = 2) out vec2 texCoord;
 
 void main() {
     Vertex vertex = PushConstants.vertBuffer.vertices[gl_VertexIndex];
     
     gl_Position = PushConstants.proj * PushConstants.view * PushConstants.model * 
                     vec4(vertex.pos + PushConstants.objPos, 1.0f);
-    fragColor = vertex.color.rgb;
-    fragTexCoord = vertex.texCoord;
+    v_norm = vertex.normal;
+    v_pos = vertex.pos;
+    texCoord = vertex.texCoord;
 }

src/types.h

@@ -32,6 +32,7 @@ public:
   struct GPUPushConstants {
     VkDeviceAddress vertexBuffer;
     glm::vec3 objPosition;
+    glm::vec3 lightPos;
     int textureID;
     glm::mat4 model;
     glm::mat4 view;