cleanup and refactoring

raytracer/ray_tracing_gltf/shaders/frag_shader.frag

@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2019-2021, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-FileCopyrightText: Copyright (c) 2019-2021 NVIDIA CORPORATION
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#version 450
+#extension GL_ARB_separate_shader_objects : enable
+#extension GL_EXT_nonuniform_qualifier : enable
+#extension GL_GOOGLE_include_directive : enable
+#extension GL_EXT_scalar_block_layout : enable
+
+#extension GL_EXT_shader_explicit_arithmetic_types_int64 : require
+#extension GL_EXT_buffer_reference2 : require
+
+#include "gltf.glsl"
+#include "host_device.h"
+
+layout(push_constant) uniform _PushConstantRaster
+{
+  PushConstantRaster pcRaster;
+};
+
+// clang-format off
+// Incoming 
+layout(location = 1) in vec3 i_worldPos;
+layout(location = 2) in vec3 i_worldNrm;
+layout(location = 3) in vec3 i_viewDir;
+layout(location = 4) in vec2 i_texCoord;
+// Outgoing
+layout(location = 0) out vec4 o_color;
+// Buffers
+layout(buffer_reference, scalar) buffer  GltfMaterial { GltfShadeMaterial m[]; };
+layout(set = 0, binding = eSceneDesc ) readonly buffer SceneDesc_ { SceneDesc sceneDesc; } ;
+layout(set = 0, binding = eTextures) uniform sampler2D[] textureSamplers;
+// clang-format on
+
+
+void main()
+{
+  // Material of the object
+  GltfMaterial      gltfMat = GltfMaterial(sceneDesc.materialAddress);
+  GltfShadeMaterial mat     = gltfMat.m[pcRaster.materialId];
+
+  vec3 N = normalize(i_worldNrm);
+
+  // Vector toward light
+  vec3  L;
+  float lightIntensity = pcRaster.lightIntensity;
+  if(pcRaster.lightType == 0)
+  {
+    vec3  lDir     = pcRaster.lightPosition - i_worldPos;
+    float d        = length(lDir);
+    lightIntensity = pcRaster.lightIntensity / (d * d);
+    L              = normalize(lDir);
+  }
+  else
+  {
+    L = normalize(pcRaster.lightPosition);
+  }
+
+
+  // Diffuse
+  vec3 diffuse = computeDiffuse(mat, L, N);
+  if(mat.pbrBaseColorTexture > -1)
+  {
+    uint txtId      = mat.pbrBaseColorTexture;
+    vec3 diffuseTxt = texture(textureSamplers[nonuniformEXT(txtId)], i_texCoord).xyz;
+    diffuse *= diffuseTxt;
+  }
+
+  // Specular
+  vec3 specular = computeSpecular(mat, i_viewDir, L, N);
+
+  // Result
+  o_color = vec4(lightIntensity * (diffuse + specular), 1);
+}