Basic alpha blending works but I have no z ordering yet.

19-blending/config.json

@@ -1,12 +1,12 @@
 {
   "scene": {
     "shader": {
-      "vertex_path": "shaders/18-vert.glsl",
-      "frag_path": "shaders/18-frag.glsl"
+      "vertex_path": "shaders/19-vert.glsl",
+      "frag_path": "shaders/19-frag.glsl"
     },
     "light_shader": {
-      "vertex_path": "shaders/18-vert.glsl",
-      "frag_path": "shaders/18-lightsource.frag.glsl"
+      "vertex_path": "shaders/19-vert.glsl",
+      "frag_path": "shaders/19-lightsource.frag.glsl"
     },
     "materials": {
       "default": {
@@ -30,12 +30,29 @@
       "metal_floor": {
         "directory": "assets",
         "model_path": "metal_floor.glb"
+      },
+      "grass": {
+        "directory": "assets",
+        "model_path": "grass.glb"
       }
     },
     "things": [
-      {"model": "marble_cube", "position": [-1.0,  0.0,  -1.0], "material": "default"},
-      {"model": "marble_cube", "position": [2.0,  0.0, 0.0], "material": "default"},
-      {"model": "metal_floor", "position": [0.0, 0.0, 0.0], "material": "shiny"}
+      {"model": "marble_cube", "position": [-1.0,  0.0,  -1.0],
+        "rotation": {"angle": 0.0, "axes": [1.0, 1.0, 1.0]},
+        "scale": 1.0,
+        "material": "default"},
+      {"model": "marble_cube", "position": [2.0,  0.0, 0.0],
+        "rotation": {"angle": 0.0, "axes": [1.0, 1.0, 1.0]},
+        "scale": 1.0,
+        "material": "default"},
+      {"model": "metal_floor", "position": [0.0, 0.0, 0.0],
+        "rotation": {"angle": 0.0, "axes": [1.0, 1.0, 1.0]},
+        "scale": 1.0,
+        "material": "shiny"},
+      {"model": "grass", "position": [0.5,  0.13,  0.0],
+        "rotation": {"angle": 90.0, "axes": [1.0,0.0,0.0]},
+        "scale": 1.0,
+        "material": "default"}
     ],
     "camera": {
       "position": [0.0, 0.1, 3.0],

19-blending/shaders/19-frag.glsl

@@ -0,0 +1,168 @@
+#version 330 core
+struct Material {
+  sampler2D diffuse;
+  sampler2D specular;
+  float shininess;
+};
+
+out vec4 FragColor;
+in vec3 FragPos;
+in vec3 Normal;
+in vec2 TexCoords;
+
+uniform vec3 viewPos;
+uniform Material material;
+
+struct DirLight {
+  vec3 direction;
+  vec3 ambient;
+  vec3 diffuse;
+  vec3 specular;
+};
+
+struct PointLight {
+  vec3 position;
+  vec3 ambient;
+  vec3 diffuse;
+  vec3 specular;
+  float constant;
+  float linear;
+  float quadratic;
+};
+
+struct SpotLight {
+  vec3 direction;
+  vec3 position;
+  vec3 diffuse;
+  vec3 specular;
+  vec3 ambient;
+
+  float constant;
+  float linear;
+  float quadratic;
+  float cut_off;
+  float outer_cut_off;
+};
+
+
+#define MAX_LIGHTS 4
+uniform int pointLightCount = 0;
+uniform PointLight pointLights[MAX_LIGHTS];
+
+uniform int dirLightCount = 0;
+uniform DirLight dirLights[MAX_LIGHTS];
+
+uniform int spotLightCount = 0;
+uniform SpotLight spotLights[MAX_LIGHTS];
+
+
+float near = 0.1;
+float far = 100.0;
+
+vec4 CalcDirLight(vec4 mat_tex, vec4 spec_tex, DirLight light, vec3 normal, vec3 viewDir)
+{
+  vec3 lightDir = normalize(-light.direction);
+  // diffuse shading
+  float diff = max(dot(normal, lightDir), 0.0);
+
+  // specular shading
+  vec3 reflectDir = reflect(-lightDir, normal);
+  float spec = pow(max(dot(viewDir, reflectDir), 0.0), material.shininess);
+
+  vec4 ambient = vec4(light.ambient, 1.0) * mat_tex;
+  vec4 diffuse = vec4(light.diffuse, 1.0) * diff * mat_tex;
+  vec4 specular = vec4(light.specular, 1.0) * spec * spec_tex;
+
+  return ambient + diffuse + specular;
+}
+
+vec4 CalcPointLight(vec4 mat_tex, vec4 spec_tex, PointLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
+{
+  vec3 lightDir = normalize(light.position - fragPos);
+
+  // diffuse shading
+  float diff = max(dot(normal, lightDir), 0.0);
+
+  // specular shading
+  vec3 reflectDir = reflect(-lightDir, normal);
+  float spec = pow(max(dot(viewDir, reflectDir), 0.0), material.shininess);
+
+  // attenuation
+  float distance = length(light.position - fragPos);
+  float attenuation = 1.0 / (light.constant + light.linear * distance + light.quadratic * (distance * distance));
+
+  vec4 ambient = vec4(light.ambient, 1.0) * mat_tex;
+  vec4 diffuse = vec4(light.diffuse, 1.0) * diff * mat_tex;
+  vec4 specular = vec4(light.specular, 1.0) * spec * spec_tex;
+
+  ambient *= attenuation;
+  diffuse *= attenuation;
+  specular *= attenuation;
+
+  return ambient + diffuse + specular;
+}
+
+vec4 CalcSpotLight(vec4 mat_tex, vec4 spec_tex, SpotLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
+{
+  vec3 lightDir = normalize(light.position - fragPos);
+
+  // diffuse shading
+  float diff = max(dot(normal, lightDir), 0.0);
+
+  // specular shading
+  vec3 reflectDir = reflect(-lightDir, normal);
+  float spec = pow(max(dot(viewDir, reflectDir), 0.0), material.shininess);
+
+  // attenuation
+  float distance = length(light.position - fragPos);
+  float attenuation = 1.0 / (light.constant + light.linear * distance + light.quadratic * (distance * distance));
+
+  vec4 ambient = vec4(light.ambient, 1.0) * mat_tex;
+  vec4 diffuse = vec4(light.diffuse, 1.0) * diff * mat_tex;
+  vec4 specular = vec4(light.specular, 1.0) * spec * spec_tex;
+
+  float theta = dot(lightDir, normalize(-light.direction));
+  float epsilon = light.cut_off - light.outer_cut_off;
+  float intensity = clamp((theta - light.outer_cut_off) / epsilon, 0.0, 1.0);
+  diffuse *= intensity;
+  specular *= intensity;
+
+  ambient *= attenuation;
+  diffuse *= attenuation;
+  specular *= attenuation;
+
+  return ambient + diffuse + specular;
+}
+
+float LinearizeDepth(float depth)
+{
+  float ndc = depth * 2.0 - 1.0;
+  return (2.0 * near * far) / (far + near - ndc * (far - near));
+}
+
+void main()
+{
+  vec4 mat_tex = texture(material.diffuse, TexCoords);
+  vec4 spec_tex = texture(material.specular, TexCoords);
+
+  vec3 norm = normalize(Normal);
+  vec3 viewDir = normalize(viewPos - FragPos);
+
+  // kick it off with the first dirlight
+  vec4 result = CalcDirLight(mat_tex, spec_tex, dirLights[0], norm, viewDir);
+
+  // then augment with more (off by one)
+  for(int i = 1; i < dirLightCount; i++) {
+    result += CalcDirLight(mat_tex, spec_tex, dirLights[i], norm, viewDir);
+  }
+
+  for(int i = 0; i < pointLightCount; i++) {
+    result += CalcPointLight(mat_tex, spec_tex, pointLights[i], norm, FragPos, viewDir);
+  }
+
+  for(int i = 0; i < spotLightCount; i++) {
+    result += CalcSpotLight(mat_tex, spec_tex, spotLights[i], norm, FragPos, viewDir);
+  }
+
+  FragColor = result;
+}

19-blending/shaders/19-lightsource.frag.glsl

@@ -0,0 +1,9 @@
+#version 330 core
+out vec4 FragColor;
+
+uniform vec3 diffuse;
+
+void main()
+{
+    FragColor = vec4(diffuse, 1.0); // set all 4 vector values to 1.0
+}

19-blending/shaders/19-vert.glsl

@@ -0,0 +1,20 @@
+#version 330 core
+layout (location = 0) in vec3 aPos;
+layout (location = 1) in vec3 aNormal;
+layout (location = 2) in vec2 aTexCoords;
+
+out vec3 FragPos;
+out vec3 Normal;
+out vec2 TexCoords;
+
+uniform mat4 model;
+uniform mat4 view;
+uniform mat4 projection;
+
+void main()
+{
+    gl_Position = projection * view * model * vec4(aPos, 1.0f);
+    FragPos = vec3(model * vec4(aPos, 1.0));
+    Normal = mat3(transpose(inverse(model))) * aNormal;
+    TexCoords = aTexCoords;
+}

19-blending/src/components.hpp

@@ -75,14 +75,22 @@ namespace components {
   ENROLL_COMPONENT(Model, directory, model_path);
 
   using Position = glm::vec3;
+  struct Rotation {
+    float angle = 0;
+    glm::vec3 axes{1.0f, 0.0f, 0.0f};
+  };
+
+  ENROLL_COMPONENT(Rotation, angle, axes);
 
   struct Thing {
     std::string model;
-    Position position;
     std::string material;
+    Position position;
+    Rotation rotation;
+    float scale;
   };
 
-  ENROLL_COMPONENT(Thing, model, position, material);
+  ENROLL_COMPONENT(Thing, model, material, position, rotation, scale);
 
   struct Shader {
     std::string vertex_path;

19-blending/src/main.cpp

@@ -66,24 +66,33 @@ void process_input(GLFWwindow *window, Scene& scene) {
   }
 
   if(glfwGetKey(window, GLFW_KEY_M) == GLFW_PRESS) {
-    scene.spawn("marble_cube", scene.camera.position);
+    components::Rotation rotation{90.0f, {1.0f, 0.0f, 0.0f}};
+    scene.spawn("grass", scene.camera.position, rotation);
   }
 
   if(glfwGetKey(window, GLFW_KEY_L) == GLFW_PRESS) {
     for(auto& light : scene.light.directional) {
       light.adjust(-0.01f);
     }
+
+    scene.shader.apply_lighting(scene.light);
   }
 
   if(glfwGetKey(window, GLFW_KEY_P) == GLFW_PRESS) {
     for(auto& light : scene.light.directional) {
       light.adjust(0.01f);
     }
+
+    scene.shader.apply_lighting(scene.light);
   }
 }
 
 Scene setup() {
   glEnable(GL_DEPTH_TEST);
+  glEnable(GL_BLEND);
+
+  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
   glDepthFunc(GL_LESS);
 
   components::Scene config = utils::load_scene_config("config.json");

19-blending/src/model.cpp

@@ -31,6 +31,8 @@ unsigned int image_to_texture(unsigned char *data, int width, int height, int nr
 
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+  glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+  glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 

19-blending/src/scene.cpp

@@ -10,17 +10,18 @@ void Scene::update() {
   camera.update(deltaTime);
 }
 
-void Scene::draw_model(Shader& with_shader, Model& scene_model, Material& material, glm::vec3& position, float scale)
+void Scene::draw_thing(Shader& with_shader, Thing& thing)
 {
-  with_shader.apply_material(material);
+  with_shader.apply_material(thing.material);
 
   glm::mat4 model = glm::mat4(1.0f);
-  model = glm::translate(model, position);
-  model = glm::scale(model, glm::vec3(scale, scale, scale));
+  model = glm::translate(model, thing.position);
+  model = glm::rotate(model, glm::radians(thing.rotation.angle), thing.rotation.axes);
+  model = glm::scale(model, glm::vec3(thing.scale));
 
   with_shader.setMat4("model", model);
 
-  scene_model.draw(with_shader);
+  thing.model.draw(with_shader);
 }
 
 void Scene::render(GLFWwindow* window) {
@@ -47,7 +48,7 @@ void Scene::render(GLFWwindow* window) {
   }
 
   for(auto& thing : things) {
-    draw_model(shader, thing.model, thing.material, thing.position);
+    draw_thing(shader, thing);
   }
 }
 
@@ -55,13 +56,15 @@ void Scene::cleanup() {
   shader.cleanup();
 }
 
-void Scene::spawn(const std::string& name, components::Position& position) {
+void Scene::spawn(const std::string& name, components::Position& position, components::Rotation& rotation) {
   if(models.contains(name)) {
     things.emplace_back(
           name,
           models.at(name),
+          materials.at("default"),
           position,
-        materials.at("default"));
+          rotation,
+          1.0f);
   } else {
     dbc::log($F("No model named: {}", name));
   }

19-blending/src/scene.hpp

@@ -16,8 +16,10 @@
 struct Thing {
   std::string name;
   Model& model;
-  components::Position position;
   Material& material;
+  components::Position position;
+  components::Rotation rotation;
+  float scale;
 };
 
 struct Scene {
@@ -54,8 +56,10 @@ struct Scene {
       things.emplace_back(
           thing.model,
           models.at(thing.model),
+          materials.at(thing.material),
           thing.position,
-          materials.at(thing.material));
+          thing.rotation,
+          thing.scale);
     }
 
     shader.use();
@@ -63,8 +67,8 @@ struct Scene {
   }
 
   void update();
-  void draw_model(Shader& with_shader, Model& scene_model, Material& material, glm::vec3& position, float scale=1.0f);
+  void draw_thing(Shader& with_shader, Thing& thing);
   void render(GLFWwindow* window);
   void cleanup();
-  void spawn(const std::string& name, components::Position& position);
+  void spawn(const std::string& name, components::Position& position, components::Rotation& rotation);
 };

19-blending/tests/config.json

@@ -62,10 +62,11 @@
     "directory": "assets",
     "model_path": "create.obj"
   },
-  "thing_test": {
-    "model": "crate",
-    "position": [0.0, 0.0, 0.0],
-    "material": "crate"
+  "thing_test":
+      {"model": "grass", "position": [2.5,  0.0,  0.0],
+        "rotation": {"angle": 90.0, "axes": [0.0,1.0,0.0,0.0]},
+        "scale": 1.0,
+        "material": "default"
       },
   "shader_test": {
     "vertex_path": "shaders/16-vert.glsl",