New Asset iteration

Signed-off-by: Robear Selwans <robear.selwans@outlook.com>

assets/shaders/_builtins/constants.glsl

@@ -0,0 +1,6 @@
+#ifndef EV_GLSL_CONSTANTS_H
+#define EV_GLSL_CONSTANTS_H
+
+#define PI 3.1415926538
+
+#endif

assets/shaders/_builtins/srgb_ops.glsl

@@ -0,0 +1,22 @@
+#ifndef EV_GLSL_SRGB_OPS_H
+#define EV_GLSL_SRGB_OPS_H
+
+vec4 LinearToSRGB(vec4 linearRGB)
+{
+    bvec4 cutoff = lessThan(linearRGB, vec4(0.0031308));
+    vec4 higher = vec4(1.055)*pow(linearRGB, vec4(1.0/2.4)) - vec4(0.055);
+    vec4 lower = linearRGB * vec4(12.92);
+
+    return mix(higher, lower, cutoff);
+}
+
+vec4 SRGBToLinear(vec4 sRGB)
+{
+    bvec4 cutoff = lessThan(sRGB, vec4(0.04045));
+    vec4 higher = pow((sRGB + vec4(0.055))/vec4(1.055), vec4(2.4));
+    vec4 lower = sRGB/vec4(12.92);
+
+    return mix(higher, lower, cutoff);
+}
+
+#endif

assets/shaders/_builtins/types.glsl

@@ -0,0 +1,26 @@
+#ifndef EV_GLSL_TYPES_H
+#define EV_GLSL_TYPES_H
+
+struct Material {
+  vec4 baseColor;
+  uint albedoTexture;
+
+  uint normalTexture;
+
+  float metallicFactor;
+  float roughnessFactor;
+  uint metallicRoughnessTexture;
+
+  vec4 emissiveFactor;
+  uint emissiveTexture;
+};
+
+struct Vertex {
+  vec4 position;
+  vec4 normal;
+  vec2 uv[2];
+  vec4 tangent;
+  vec4 bitangent; // No longer needed. // TODO remove
+};
+
+#endif

assets/shaders/default.frag

@@ -1,16 +1,9 @@
 #version 450
 #extension GL_EXT_nonuniform_qualifier : require
 
-struct Material {
-  vec4 baseColor;
-  uint albedoTexture;
-
-  uint normalTexture;
-
-  float metallicFactor;
-  float roughnessFactor;
-  uint metallicRoughnessTexture;
-};
+#include <shaders://_builtins/types.glsl>
+#include <shaders://_builtins/constants.glsl>
+#include <shaders://_builtins/srgb_ops.glsl>
 
 struct Light {
   vec3 color;
@@ -21,7 +14,7 @@ struct Scene {
   uint lightsCount;
 };
 
-vec3 directional_light = vec3(1.0);
+vec3 pointLightColor = vec3(1.0, 1.0, 1.0);
 
 layout( push_constant ) uniform constants
 {
@@ -45,35 +38,130 @@ layout(set = 2, binding = 3) buffer MaterialBuffer {
 
 layout(set = 2, binding = 4) uniform sampler2D texSampler[];
 
-layout(location = 0) in vec2 uv;
-layout(location = 1) smooth in mat3 TBN;
+layout(location = 0) in vec3 position;
+layout(location = 1) in vec2 uv;
+layout(location = 2) in vec3 cameraPos;
+layout(location = 3) in vec3 pointLightPos;
+layout(location = 4) smooth in mat3 TBN;
 
 layout(location = 0) out vec4 outColor;
 
-void main() {
+float DistributionGGX(vec3 N, vec3 H, float a)
+{
+  float a2 = a*a;
+  float NdotH = max(dot(N,H),0.0);
+  float NdotH2 = NdotH*NdotH;
+
+  float num = a2;
+  float denom = (NdotH2 * (a2 - 1.0) + 1.0);
+  denom = PI * denom * denom;
+
+  return num/denom;
+}
+
+float GeometrySchlickGGX(float NdotV, float k)
+{
+    float nom   = NdotV;
+    float denom = NdotV * (1.0 - k) + k;
+
+    return nom / denom;
+}
+  
+float GeometrySmith(vec3 N, vec3 V, vec3 L, float k)
+{
+    float NdotV = max(dot(N, V), 0.0);
+    float NdotL = max(dot(N, L), 0.0);
+    float ggx1 = GeometrySchlickGGX(NdotV, k);
+    float ggx2 = GeometrySchlickGGX(NdotL, k);
+
+    return ggx1 * ggx2;
+}
+
+vec3 fresnelSchlick(float cosTheta, vec3 F0)
+{
+    return F0 + (1.0 - F0) * pow(1.0 - cosTheta, 5.0);
+}
+
+void main() 
+{
   Material material  = MaterialBuffers.materials[ PushConstants.materialBufferIndex ];
 
+  vec3 albedo;
+  float alpha;
+  if(material.albedoTexture == 0) {
+    albedo = material.baseColor.xyz;
+  } else {
+    vec4 sampledColor = texture(texSampler[material.albedoTexture], uv);
+    if(sampledColor.a < 0.5) {
+      discard;
+    }
+    albedo = sampledColor.rgb;
+    alpha = sampledColor.a;
+  }
+
   vec3 out_normal;
   if(material.normalTexture == 0) {
     out_normal = TBN[2].xyz;
   } else {
-    vec3 sampled_normal = texture(texSampler[material.normalTexture], uv).rgb;
+    vec3 sampled_normal = LinearToSRGB(texture(texSampler[material.normalTexture], uv)).rgb;
     sampled_normal = 2.0 * sampled_normal - vec3(1.0);
     out_normal = normalize(TBN * sampled_normal);
   }
 
-
-  float intensity = dot(out_normal, normalize(directional_light)) + 0.2;
-
-  vec3 inColor;
-  if(material.albedoTexture == 0) {
-    inColor = material.baseColor.xyz;
+  float metallicFactor;
+  float roughnessFactor;
+  float ao;
+  if(material.metallicRoughnessTexture == 0) {
+    metallicFactor = material.metallicFactor;
+    roughnessFactor = material.roughnessFactor;
   } else {
-    inColor = texture(texSampler[material.albedoTexture], uv).xyz;
+    vec4 sampled_mr = LinearToSRGB(texture(texSampler[material.metallicRoughnessTexture], uv));
+    ao = sampled_mr.r;
+    roughnessFactor = sampled_mr.g;
+    metallicFactor = sampled_mr.b;
   }
 
-  outColor = vec4(inColor * intensity, 1.0);
-  // outColor = vec4(inColor, 1.0);
-  // outColor = vec4(vec3(intensity), 1.0);
-  // outColor = vec4(out_normal, 1.0);
+  vec3 emissiveness;
+  if(material.emissiveTexture == 0) {
+    emissiveness = vec3(0.0);
+  } else {
+    emissiveness = texture(texSampler[material.emissiveTexture], uv).rgb;
+    emissiveness *= material.emissiveFactor.xyz;
+  }
+
+  float lightIntensity = 2.0;
+
+  vec3 V = normalize(cameraPos - position);
+  vec3 L = normalize(pointLightPos - position);
+  vec3 H = normalize(V + L);
+  vec3 N = out_normal;
+  float distance    = length(pointLightPos - position);
+  float attenuation = 1.0 / (distance * distance);
+  vec3 radiance     = pointLightColor * attenuation * lightIntensity;
+
+  vec3 F0 = vec3(0.04); 
+  F0      = mix(F0, albedo, metallicFactor);
+
+  vec3 F  = fresnelSchlick(max(dot(H, V), 0.0), F0);
+  float NDF = DistributionGGX(N, H, roughnessFactor);
+  float G   = GeometrySmith(N, V, L, roughnessFactor);
+
+  vec3 numerator    = NDF * G * F;
+  float denominator = 4.0 * max(dot(N, V), 0.0) * max(dot(N, L), 0.0);
+  vec3 specular     = numerator / max(denominator, 0.001);
+
+  vec3 kS = F;
+  vec3 kD = vec3(1.0) - kS;
+  kD *= 1.0 - metallicFactor;
+
+  float NdotL = max(dot(N, L), 0.0);        
+  vec3 Lo = (kD * albedo / PI + specular) * radiance * NdotL;
+
+  vec3 ambient = vec3(0.03) * albedo * ao;
+
+  vec3 color   = ambient + Lo;
+  color += emissiveness;
+  color = color / (color + vec3(1.0));
+
+  outColor = vec4(color, alpha);
 }

assets/shaders/default.vert

@@ -1,24 +1,7 @@
 #version 450
 #extension GL_EXT_nonuniform_qualifier : require
 
-struct Material {
-  vec4 baseColor;
-  uint albedoTexture;
-
-  uint normalTexture;
-
-  float metallicFactor;
-  float roughnessFactor;
-  uint metallicRoughnessTexture;
-};
-
-struct Vertex {
-  vec4 position;
-  vec4 normal;
-  vec2 uv[2];
-  vec4 tangent;
-  vec4 bitangent; // No longer needed. // TODO remove
-};
+#include <shaders://_builtins/types.glsl>
 
 struct Light {
   vec3 color;
@@ -60,8 +43,13 @@ layout(set = 2, binding = 2) buffer IndexBuffer {
 
 layout(set = 2, binding = 4) uniform sampler2D texSampler[];
 
-layout(location = 0) out vec2 uv;
-layout(location = 1) smooth out mat3 TBN;
+layout(location = 0) out vec3 position;
+layout(location = 1) out vec2 uv;
+layout(location = 2) out vec3 cameraPos;
+layout(location = 3) out vec3 lightPos;
+layout(location = 4) smooth out mat3 TBN;
+
+vec4 pointLightPos = vec4(0.0, 2.0, 0.0, 1.0);
 
 void main()
 {
@@ -79,5 +67,11 @@ void main()
   /* vec3 B = normalize(cross(N, T)); */
   TBN = mat3(T, B, N);
 
-  gl_Position = Camera.projection * Camera.view * PushConstants.render_matrix * vec4(vertex.position.xyz, 1.0);
+  mat4 VP = Camera.projection * Camera.view;
+  mat4 MVP =  VP * PushConstants.render_matrix;
+  gl_Position = MVP * vec4(vertex.position.xyz, 1.0);
+  position = (PushConstants.render_matrix * vec4(vertex.position.xyz, 1.0)).xyz;
+  cameraPos = inverse(Camera.view)[3].xyz;
+  /* lightPos = (pointLightPos).xyz; */
+  lightPos = cameraPos;
 }