Started a simple font text class to do font rendering.

32-text-rendering/shaders/08-frag.glsl

@@ -0,0 +1,43 @@
+#version 330 core
+struct Material {
+  vec3 ambient;
+  vec3 diffuse;
+  vec3 specular;
+  float shininess;
+};
+
+struct Light {
+  vec3 position;
+  vec3 ambient;
+  vec3 diffuse;
+  vec3 specular;
+};
+
+uniform Light light;
+
+uniform Material material;
+out vec4 FragColor;
+in vec3 FragPos;
+in vec3 Normal;
+
+uniform vec3 viewPos;
+
+void main()
+{
+  vec3 ambient = light.ambient * material.ambient;
+
+  vec3 norm = normalize(Normal);
+  vec3 lightDir = normalize(light.position - FragPos);
+  float diff = max(dot(norm, lightDir), 0.0);
+  vec3 diffuse = light.diffuse * (diff * material.diffuse);
+
+  vec3 viewDir = normalize(viewPos - FragPos);
+  vec3 reflectDir = reflect(-lightDir, norm);
+
+  float spec = pow(max(dot(viewDir, reflectDir), 0.0), material.shininess);
+  vec3 specular = light.specular * (material.specular * spec);
+
+  vec3 result = ambient + diffuse + specular;
+
+  FragColor = vec4(result, 1.0);
+}

32-text-rendering/shaders/08-lightsource.frag.glsl

@@ -0,0 +1,16 @@
+#version 330 core
+out vec4 FragColor;
+
+struct Light {
+  vec3 position;
+  vec3 ambient;
+  vec3 diffuse;
+  vec3 specular;
+};
+
+uniform Light light;
+
+void main()
+{
+    FragColor = vec4(light.diffuse, 1.0); // set all 4 vector values to 1.0
+}

32-text-rendering/shaders/08-vert.glsl

@@ -0,0 +1,17 @@
+#version 330 core
+layout (location = 0) in vec3 aPos;
+layout (location = 1) in vec3 aNormal;
+
+out vec3 FragPos;
+out vec3 Normal;
+
+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;
+}

32-text-rendering/shaders/10.1.instancing.fs

@@ -0,0 +1,9 @@
+#version 330 core
+out vec4 FragColor;
+
+in vec3 fColor;
+
+void main()
+{
+    FragColor = vec4(fColor, 1.0);
+}

32-text-rendering/shaders/10.1.instancing.vs

@@ -0,0 +1,12 @@
+#version 330 core
+layout (location = 0) in vec2 aPos;
+layout (location = 1) in vec3 aColor;
+layout (location = 2) in vec2 aOffset;
+
+out vec3 fColor;
+
+void main()
+{
+    fColor = aColor;
+    gl_Position = vec4(aPos + aOffset, 0.0, 1.0);
+}

32-text-rendering/shaders/11-frag.glsl

@@ -0,0 +1,46 @@
+#version 330 core
+struct Material {
+  sampler2D diffuse;
+  sampler2D specular;
+  float shininess;
+};
+
+struct Light {
+  vec3 position;
+  vec3 diffuse;
+  vec3 specular;
+  vec3 ambient;
+};
+
+out vec4 FragColor;
+in vec3 FragPos;
+in vec3 Normal;
+in vec2 TexCoords;
+
+uniform vec3 viewPos;
+uniform Light light;
+uniform Material material;
+
+void main()
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+
+  vec3 ambient = light.ambient * mat_tex;
+
+  vec3 norm = normalize(Normal);
+  vec3 lightDir = normalize(light.position - FragPos);
+  float diff = max(dot(norm, lightDir), 0.0);
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+
+  vec3 viewDir = normalize(viewPos - FragPos);
+  vec3 reflectDir = reflect(-lightDir, norm);
+
+  float spec = pow(max(dot(viewDir, reflectDir), 0.0), material.shininess);
+
+  vec3 specular = light.specular * spec * spec_tex;
+
+  vec3 result = ambient + diffuse + specular;
+
+  FragColor = vec4(result, 1.0);
+}

32-text-rendering/shaders/11-lightsource.frag.glsl

@@ -0,0 +1,16 @@
+#version 330 core
+out vec4 FragColor;
+
+struct Light {
+  vec3 position;
+  vec3 ambient;
+  vec3 diffuse;
+  vec3 specular;
+};
+
+uniform Light light;
+
+void main()
+{
+    FragColor = vec4(light.diffuse, 1.0); // set all 4 vector values to 1.0
+}

32-text-rendering/shaders/11-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;
+}

32-text-rendering/shaders/12-frag.glsl

@@ -0,0 +1,67 @@
+#version 330 core
+struct Material {
+  sampler2D diffuse;
+  sampler2D specular;
+  float shininess;
+};
+
+struct Light {
+  vec3 direction;
+  vec3 position;
+  vec3 diffuse;
+  vec3 specular;
+  vec3 ambient;
+
+  float constant;
+  float linear;
+  float quadratic;
+  float cutOff;
+  float outerCutOff;
+};
+
+out vec4 FragColor;
+in vec3 FragPos;
+in vec3 Normal;
+in vec2 TexCoords;
+
+uniform vec3 viewPos;
+uniform Light light;
+uniform Material material;
+
+void main()
+{
+  vec3 lightDir = normalize(light.position - FragPos);
+
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+  vec3 ambient = light.ambient * mat_tex;
+
+  vec3 norm = normalize(Normal);
+  float diff = max(dot(norm, lightDir), 0.0);
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+
+  vec3 viewDir = normalize(viewPos - FragPos);
+  vec3 reflectDir = reflect(-lightDir, norm);
+
+  float spec = pow(max(dot(viewDir, reflectDir), 0.0), material.shininess);
+
+  vec3 specular = light.specular * spec * spec_tex;
+
+  // splotlight
+  float theta = dot(lightDir, normalize(-light.direction));
+  float epsilon = light.cutOff - light.outerCutOff;
+  float intensity = clamp((theta - light.outerCutOff) / epsilon, 0.0, 1.0);
+  diffuse *= intensity;
+  specular *= intensity;
+
+  // determine attenuation based on light distance
+  float distance = length(light.position - FragPos);
+  float attenuation = 1.0 / (light.constant + light.linear * distance + light.quadratic * (distance * distance));
+
+  ambient *= attenuation;
+  diffuse *= attenuation;
+  specular *= attenuation;
+
+  vec3 result = ambient + diffuse + specular;
+  FragColor = vec4(result, 1.0);
+}

32-text-rendering/shaders/12-lightsource.frag.glsl

@@ -0,0 +1,16 @@
+#version 330 core
+out vec4 FragColor;
+
+struct Light {
+  vec3 position;
+  vec3 ambient;
+  vec3 diffuse;
+  vec3 specular;
+};
+
+uniform Light light;
+
+void main()
+{
+    FragColor = vec4(light.diffuse, 1.0); // set all 4 vector values to 1.0
+}

32-text-rendering/shaders/12-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;
+}

32-text-rendering/shaders/13-frag.glsl

@@ -0,0 +1,150 @@
+#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 cutOff;
+  float outerCutOff;
+};
+
+
+#define NR_POINT_LIGHTS 4
+uniform int pointLightCount;
+uniform PointLight pointLights[NR_POINT_LIGHTS];
+uniform DirLight dirLight;
+uniform SpotLight spotLight;
+
+vec3 CalcDirLight(DirLight light, vec3 normal, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+
+  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);
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * spec * spec_tex;
+
+  return ambient + diffuse + specular;
+}
+
+vec3 CalcPointLight(PointLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+  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));
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * spec * spec_tex;
+
+  ambient *= attenuation;
+  diffuse *= attenuation;
+  specular *= attenuation;
+
+  return ambient + diffuse + specular;
+}
+
+vec3 CalcSpotLight(SpotLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+  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));
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * spec * spec_tex;
+
+  float theta = dot(lightDir, normalize(-light.direction));
+  float epsilon = light.cutOff - light.outerCutOff;
+  float intensity = clamp((theta - light.outerCutOff) / epsilon, 0.0, 1.0);
+  diffuse *= intensity;
+  specular *= intensity;
+
+  ambient *= attenuation;
+  diffuse *= attenuation;
+  specular *= attenuation;
+
+  return ambient + diffuse + specular;
+}
+
+void main()
+{
+  vec3 norm = normalize(Normal);
+  vec3 viewDir = normalize(viewPos - FragPos);
+
+  vec3 result = CalcDirLight(dirLight, norm, viewDir);
+
+  for(int i = 0; i < pointLightCount; i++) {
+    result += CalcPointLight(pointLights[i], norm, FragPos, viewDir);
+  }
+
+  result += CalcSpotLight(spotLight, norm, FragPos, viewDir);
+
+  FragColor = vec4(result, 1.0);
+}

32-text-rendering/shaders/13-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
+}

32-text-rendering/shaders/13-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;
+}

32-text-rendering/shaders/14-frag.glsl

@@ -0,0 +1,150 @@
+#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 cutOff;
+  float outerCutOff;
+};
+
+
+#define NR_POINT_LIGHTS 4
+uniform int pointLightCount;
+uniform PointLight pointLights[NR_POINT_LIGHTS];
+uniform DirLight dirLight;
+uniform SpotLight spotLight;
+
+vec3 CalcDirLight(DirLight light, vec3 normal, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+
+  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);
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * spec * spec_tex;
+
+  return ambient + diffuse + specular;
+}
+
+vec3 CalcPointLight(PointLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+  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));
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * spec * spec_tex;
+
+  ambient *= attenuation;
+  diffuse *= attenuation;
+  specular *= attenuation;
+
+  return ambient + diffuse + specular;
+}
+
+vec3 CalcSpotLight(SpotLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+  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));
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * spec * spec_tex;
+
+  float theta = dot(lightDir, normalize(-light.direction));
+  float epsilon = light.cutOff - light.outerCutOff;
+  float intensity = clamp((theta - light.outerCutOff) / epsilon, 0.0, 1.0);
+  diffuse *= intensity;
+  specular *= intensity;
+
+  ambient *= attenuation;
+  diffuse *= attenuation;
+  specular *= attenuation;
+
+  return ambient + diffuse + specular;
+}
+
+void main()
+{
+  vec3 norm = normalize(Normal);
+  vec3 viewDir = normalize(viewPos - FragPos);
+
+  vec3 result = CalcDirLight(dirLight, norm, viewDir);
+
+  for(int i = 0; i < pointLightCount; i++) {
+    result += CalcPointLight(pointLights[i], norm, FragPos, viewDir);
+  }
+
+  result += CalcSpotLight(spotLight, norm, FragPos, viewDir);
+
+  FragColor = vec4(result, 1.0);
+}

32-text-rendering/shaders/14-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
+}

32-text-rendering/shaders/14-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;
+}

32-text-rendering/shaders/16-frag.glsl

@@ -0,0 +1,162 @@
+#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];
+
+vec3 CalcDirLight(DirLight light, vec3 normal, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+
+  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);
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * spec * spec_tex;
+
+  return ambient + diffuse + specular;
+}
+
+vec3 CalcPointLight(PointLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+  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));
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * spec * spec_tex;
+
+  ambient *= attenuation;
+  diffuse *= attenuation;
+  specular *= attenuation;
+
+  return ambient + diffuse + specular;
+}
+
+vec3 CalcSpotLight(SpotLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+  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));
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * 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;
+}
+
+void main()
+{
+  vec3 norm = normalize(Normal);
+  vec3 viewDir = normalize(viewPos - FragPos);
+
+  // kick it off with the first dirlight
+  vec3 result = CalcDirLight(dirLights[0], norm, viewDir);
+
+  // then augment with more (off by one)
+  for(int i = 1; i < dirLightCount; i++) {
+    result += CalcDirLight(dirLights[i], norm, viewDir);
+  }
+
+  for(int i = 0; i < pointLightCount; i++) {
+    result += CalcPointLight(pointLights[i], norm, FragPos, viewDir);
+  }
+
+  for(int i = 0; i < spotLightCount; i++) {
+    result += CalcSpotLight(spotLights[i], norm, FragPos, viewDir);
+  }
+
+  FragColor = vec4(result, 1.0);
+}

32-text-rendering/shaders/16-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
+}

32-text-rendering/shaders/16-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;
+}

32-text-rendering/shaders/17-frag.glsl

@@ -0,0 +1,162 @@
+#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];
+
+vec3 CalcDirLight(DirLight light, vec3 normal, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+
+  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);
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * spec * spec_tex;
+
+  return ambient + diffuse + specular;
+}
+
+vec3 CalcPointLight(PointLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+  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));
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * spec * spec_tex;
+
+  ambient *= attenuation;
+  diffuse *= attenuation;
+  specular *= attenuation;
+
+  return ambient + diffuse + specular;
+}
+
+vec3 CalcSpotLight(SpotLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+  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));
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * 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;
+}
+
+void main()
+{
+  vec3 norm = normalize(Normal);
+  vec3 viewDir = normalize(viewPos - FragPos);
+
+  // kick it off with the first dirlight
+  vec3 result = CalcDirLight(dirLights[0], norm, viewDir);
+
+  // then augment with more (off by one)
+  for(int i = 1; i < dirLightCount; i++) {
+    result += CalcDirLight(dirLights[i], norm, viewDir);
+  }
+
+  for(int i = 0; i < pointLightCount; i++) {
+    result += CalcPointLight(pointLights[i], norm, FragPos, viewDir);
+  }
+
+  for(int i = 0; i < spotLightCount; i++) {
+    result += CalcSpotLight(spotLights[i], norm, FragPos, viewDir);
+  }
+
+  FragColor = vec4(result, 1.0);
+}

32-text-rendering/shaders/17-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
+}

32-text-rendering/shaders/17-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;
+}

32-text-rendering/shaders/18-frag.glsl

@@ -0,0 +1,176 @@
+#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;
+
+vec3 CalcDirLight(DirLight light, vec3 normal, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+
+  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);
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * spec * spec_tex;
+
+  return ambient + diffuse + specular;
+}
+
+vec3 CalcPointLight(PointLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+  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));
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * spec * spec_tex;
+
+  ambient *= attenuation;
+  diffuse *= attenuation;
+  specular *= attenuation;
+
+  return ambient + diffuse + specular;
+}
+
+vec3 CalcSpotLight(SpotLight light, vec3 normal, vec3 fragPos, vec3 viewDir)
+{
+  vec3 mat_tex = vec3(texture(material.diffuse, TexCoords));
+  vec3 spec_tex = vec3(texture(material.specular, TexCoords));
+  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));
+
+  vec3 ambient = light.ambient * mat_tex;
+  vec3 diffuse = light.diffuse * diff * mat_tex;
+  vec3 specular = light.specular * 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()
+{
+  vec3 norm = normalize(Normal);
+  vec3 viewDir = normalize(viewPos - FragPos);
+
+  // kick it off with the first dirlight
+  vec3 result = CalcDirLight(dirLights[0], norm, viewDir);
+
+  // then augment with more (off by one)
+  for(int i = 1; i < dirLightCount; i++) {
+    result += CalcDirLight(dirLights[i], norm, viewDir);
+  }
+
+  for(int i = 0; i < pointLightCount; i++) {
+    result += CalcPointLight(pointLights[i], norm, FragPos, viewDir);
+  }
+
+  for(int i = 0; i < spotLightCount; i++) {
+    result += CalcSpotLight(spotLights[i], norm, FragPos, viewDir);
+  }
+
+  FragColor = vec4(result, 1.0);
+
+  // float depth = LinearizeDepth(gl_FragCoord.z) / far;
+  // FragColor = vec4(vec3(depth), 1.0);
+}

32-text-rendering/shaders/18-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
+}

32-text-rendering/shaders/18-outline.glsl

@@ -0,0 +1,6 @@
+#version 330 core
+out vec4 FragColor;
+
+void main() {
+  FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+}

32-text-rendering/shaders/18-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;
+}

32-text-rendering/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;
+}

32-text-rendering/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
+}

32-text-rendering/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;
+}

32-text-rendering/shaders/21-framebuffers.frag.glsl

@@ -0,0 +1,11 @@
+#version 330 core
+out vec4 FragColor;
+
+in vec2 TexCoords;
+
+uniform sampler2D texture1;
+
+void main()
+{
+    FragColor = texture(texture1, TexCoords);
+}

32-text-rendering/shaders/21-framebuffers.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;
+}

32-text-rendering/shaders/21-screen-kernel.frag.glsl

@@ -0,0 +1,38 @@
+#version 330 core
+out vec4 FragColor;
+
+in vec2 TexCoords;
+
+uniform sampler2D screenTexture;
+
+const float offset = 1.0 / 300.0;
+
+void main()
+{
+  vec2 offsets[9] = vec2[](
+      vec2(-offset,  offset), // top-left
+      vec2( 0.0f,    offset), // top-center
+      vec2( offset,  offset), // top-right
+      vec2(-offset,  0.0f),   // center-left
+      vec2( 0.0f,    0.0f),   // center-center
+      vec2( offset,  0.0f),   // center-right
+      vec2(-offset, -offset), // bottom-left
+      vec2( 0.0f,   -offset), // bottom-center
+      vec2( offset, -offset)  // bottom-right
+      );
+
+  float kernel[9] = float[](
+      1.0 / 16, 2.0 / 16, 1.0 / 16,
+      2.0 / 16, 4.0 / 16, 2.0 / 16,
+      1.0 / 16, 2.0 / 16, 1.0 / 16
+  );
+
+  vec3 col = vec3(0.0);
+
+  for(int i = 0; i < 9; i++) {
+    vec3 sampleTex = vec3(texture(screenTexture, TexCoords.st + offsets[i]));
+    col += sampleTex * kernel[i];
+  }
+
+  FragColor = vec4(col, 1.0);
+}

32-text-rendering/shaders/21-screen.frag.glsl

@@ -0,0 +1,11 @@
+#version 330 core
+out vec4 FragColor;
+
+in vec2 TexCoords;
+
+uniform sampler2D screenTexture;
+
+void main()
+{
+    FragColor = texture(screenTexture, TexCoords);
+}

32-text-rendering/shaders/21-screen.vert.glsl

@@ -0,0 +1,11 @@
+#version 330 core
+layout (location = 0) in vec2 aPos;
+layout (location = 1) in vec2 aTexCoords;
+
+out vec2 TexCoords;
+
+void main()
+{
+    gl_Position = vec4(aPos.x, aPos.y, 0.0, 1.0);
+    TexCoords = aTexCoords;
+}

32-text-rendering/shaders/24-frag.glsl

@@ -0,0 +1,17 @@
+#version 330 core
+out vec4 FragColor;
+
+in vec3 Normal;
+in vec3 FragPos;
+in vec2 TexCoords;
+
+uniform vec3 cameraPos;
+uniform samplerCube skybox;
+
+void main()
+{
+  float ratio = 1.0/1.52;
+  vec3 I = normalize(FragPos - cameraPos);
+  vec3 R = refract(I, normalize(Normal), ratio);
+  FragColor = vec4(texture(skybox, R).rgb, 1.0);
+}

32-text-rendering/shaders/24-skybox.frag.glsl

@@ -0,0 +1,11 @@
+#version 330 core
+out vec4 FragColor;
+
+in vec3 TexCoords;
+
+uniform samplerCube skybox;
+
+void main()
+{
+    FragColor = texture(skybox, TexCoords);
+}

32-text-rendering/shaders/24-skybox.vert.glsl

@@ -0,0 +1,14 @@
+#version 330 core
+layout (location = 0) in vec3 aPos;
+
+out vec3 TexCoords;
+
+uniform mat4 projection;
+uniform mat4 view;
+
+void main()
+{
+    TexCoords = aPos;
+    vec4 pos = projection * view * vec4(aPos, 1.0);
+    gl_Position = pos.xyww;
+}

32-text-rendering/shaders/24-vert.glsl

@@ -0,0 +1,21 @@
+#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;
+out vec3 Position;
+
+uniform mat4 model;
+uniform mat4 view;
+uniform mat4 projection;
+
+void main()
+{
+  Normal = mat3(transpose(inverse(model))) * aNormal;
+  FragPos = vec3(model * vec4(aPos, 1.0));
+  gl_Position = projection * view * vec4(FragPos, 1.0);
+  TexCoords = aTexCoords;
+}

32-text-rendering/shaders/26-frag.glsl

@@ -0,0 +1,17 @@
+#version 330 core
+out vec4 FragColor;
+
+in vec3 Normal;
+in vec3 FragPos;
+in vec2 TexCoords;
+
+uniform vec3 cameraPos;
+uniform samplerCube skybox;
+
+void main()
+{
+  float ratio = 1.0/1.52;
+  vec3 I = normalize(FragPos - cameraPos);
+  vec3 R = refract(I, normalize(Normal), ratio);
+  FragColor = vec4(texture(skybox, R).rgb, 1.0);
+}

32-text-rendering/shaders/26-framebuffers.frag.glsl

@@ -0,0 +1,11 @@
+#version 330 core
+out vec4 FragColor;
+
+in vec2 TexCoords;
+
+uniform sampler2D texture1;
+
+void main()
+{
+  FragColor = texture(texture1, TexCoords);
+}

32-text-rendering/shaders/26-framebuffers.vert.glsl

@@ -0,0 +1,23 @@
+#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 VS_OUT {
+    vec2 texCoords;
+} vs_out;
+
+uniform mat4 model;
+uniform mat4 view;
+uniform mat4 projection;
+
+void main()
+{
+    gl_Position = projection * view * model * vec4(aPos, 1.0);
+    FragPos = vec3(model * vec4(aPos, 1.0));
+    Normal = mat3(transpose(inverse(model))) * aNormal;
+    vs_out.texCoords = aTexCoords;
+}

32-text-rendering/shaders/26-geometry.glsl

@@ -0,0 +1,40 @@
+#version 330 core
+layout (triangles) in;
+layout (triangle_strip, max_vertices = 3) out;
+
+in VS_OUT {
+    vec2 texCoords;
+} gs_in[];
+
+out vec2 TexCoords;
+
+uniform float time;
+
+vec4 explode(vec4 position, vec3 normal)
+{
+    float magnitude = 2.0;
+    vec3 direction = normal * ((sin(time) + 1.0) / 2.0) * magnitude;
+    return position + vec4(direction, 0.0);
+}
+
+vec3 GetNormal()
+{
+    vec3 a = vec3(gl_in[0].gl_Position) - vec3(gl_in[1].gl_Position);
+    vec3 b = vec3(gl_in[2].gl_Position) - vec3(gl_in[1].gl_Position);
+    return normalize(cross(a, b));
+}
+
+void main() {
+    vec3 normal = GetNormal();
+
+    gl_Position = explode(gl_in[0].gl_Position, normal);
+    TexCoords = gs_in[0].texCoords;
+    EmitVertex();
+    gl_Position = explode(gl_in[1].gl_Position, normal);
+    TexCoords = gs_in[1].texCoords;
+    EmitVertex();
+    gl_Position = explode(gl_in[2].gl_Position, normal);
+    TexCoords = gs_in[2].texCoords;
+    EmitVertex();
+    EndPrimitive();
+}

32-text-rendering/shaders/26-vert.glsl

@@ -0,0 +1,21 @@
+#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;
+out vec3 Position;
+
+uniform mat4 model;
+uniform mat4 view;
+uniform mat4 projection;
+
+void main()
+{
+  Normal = mat3(transpose(inverse(model))) * aNormal;
+  FragPos = vec3(model * vec4(aPos, 1.0));
+  gl_Position = projection * view * vec4(FragPos, 1.0);
+  TexCoords = aTexCoords;
+}

32-text-rendering/shaders/27-framebuffers.frag.glsl

@@ -0,0 +1,11 @@
+#version 330 core
+out vec4 FragColor;
+
+in vec2 TexCoords;
+
+uniform sampler2D texture1;
+
+void main()
+{
+  FragColor = texture(texture1, TexCoords);
+}

32-text-rendering/shaders/27-framebuffers.vert.glsl

@@ -0,0 +1,26 @@
+#version 330 core
+layout (location = 0) in vec3 aPos;
+layout (location = 1) in vec3 aNormal;
+layout (location = 2) in vec2 aTexCoords;
+layout (location = 3) in vec3 aOffset;
+
+out vec3 FragPos;
+out vec3 Normal;
+out vec2 TexCoords;
+
+uniform mat4 model;
+uniform mat4 view;
+uniform mat4 projection;
+
+uniform vec3 offsets[10];
+
+void main()
+{
+  vec3 in_offset = aOffset;
+
+  vec4 offset = vec4(aPos + in_offset, 1.0);
+  gl_Position = projection * view * model * offset;
+  FragPos = vec3(model * offset);
+  Normal = mat3(transpose(inverse(model))) * aNormal;
+  TexCoords = aTexCoords;
+}

32-text-rendering/shaders/3.3.shader.fs

@@ -0,0 +1,8 @@
+#version 330 core
+out vec4 FragColor;
+in vec3 ourColor;
+
+void main()
+{
+    FragColor = vec4(ourColor, 1.0);
+}

32-text-rendering/shaders/3.3.shader.vs

@@ -0,0 +1,11 @@
+#version 330 core
+layout (location = 0) in vec3 aPos; // the position variable has attribute position 0
+layout (location = 1) in vec3 aColor;
+
+out vec3 ourColor;
+
+void main()
+{
+    gl_Position = vec4(aPos, 1.0); // see how we directly give a vec3 to vec4's constructor
+    ourColor = aColor;
+}

32-text-rendering/shaders/30-screen-bw.frag.glsl

@@ -0,0 +1,13 @@
+#version 330 core
+out vec4 FragColor;
+
+in vec2 TexCoords;
+
+uniform sampler2D screenTexture;
+
+void main()
+{
+    vec3 col = texture(screenTexture, TexCoords).rgb;
+    float grayscale = 0.2126 * col.r + 0.7152 * col.g + 0.0722 * col.b;
+    FragColor = vec4(vec3(grayscale), 1.0);
+}

32-text-rendering/shaders/30-screen.frag.glsl

@@ -0,0 +1,11 @@
+#version 330 core
+out vec4 FragColor;
+
+in vec2 TexCoords;
+
+uniform sampler2D screenTexture;
+
+void main()
+{
+    FragColor = texture(screenTexture, TexCoords);
+}

32-text-rendering/shaders/30-screen.vert.glsl

@@ -0,0 +1,11 @@
+#version 330 core
+layout (location = 0) in vec2 aPos;
+layout (location = 1) in vec2 aTexCoords;
+
+out vec2 TexCoords;
+
+void main()
+{
+    gl_Position = vec4(aPos.x, aPos.y, 0.0, 1.0);
+    TexCoords = aTexCoords;
+}

32-text-rendering/shaders/32-text.frag.glsl

@@ -0,0 +1,12 @@
+#version 330 core
+in vec2 TexCoords;
+out vec4 color;
+
+uniform sampler2D text;
+uniform vec3 textColor;
+
+void main()
+{
+    vec4 sampled = vec4(1.0, 1.0, 1.0, texture(text, TexCoords).r);
+    color = vec4(textColor, 1.0) * sampled;
+}

32-text-rendering/shaders/32-text.vert.glsl

@@ -0,0 +1,11 @@
+#version 330 core
+layout (location = 0) in vec4 vertex; // <vec2 pos, vec2 tex>
+out vec2 TexCoords;
+
+uniform mat4 projection;
+
+void main()
+{
+    gl_Position = projection * vec4(vertex.xy, 0.0, 1.0);
+    TexCoords = vertex.zw;
+}

32-text-rendering/shaders/4.2.texture.fs

@@ -0,0 +1,11 @@
+#version 330 core
+
+out vec4 FragColor;
+in vec2 TexCoord;
+
+uniform sampler2D texture1;
+
+void main()
+{
+  FragColor = texture(texture1, TexCoord);
+}

32-text-rendering/shaders/4.2.texture.vs

@@ -0,0 +1,15 @@
+#version 330 core
+layout (location = 0) in vec3 aPos;
+layout (location = 1) in vec2 aTexCoord;
+
+out vec2 TexCoord;
+
+uniform mat4 model;
+uniform mat4 view;
+uniform mat4 projection;
+
+void main()
+{
+    gl_Position = projection * view * model * vec4(aPos, 1.0f);
+    TexCoord = vec2(aTexCoord.x, aTexCoord.y);
+}