tessalation started

HydraEngine/source/ShaderFiles/landscape_shader.tese

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+// tessellation evaluation shader
+#version 450 core
+
+layout (quads, equal_spacing, ccw) in;
+
+layout(std430, binding = 1) readonly buffer positions_buffer 
+{
+	mat4 model_matrix[];
+};
+
+layout(binding = 0) uniform uniform_per_frame
+{	
+	mat4 view;
+	mat4 proj;	
+	vec3 viewer_pos;	
+	uint light_count;
+} ubo_per_frame;
+
+// received from Tessellation Control Shader - all texture coordinates for the patch vertices
+// varying input from vertex shader
+
+layout (location=0) in TC_OUT
+{
+	vec2 vsUV;
+	vec4 vsWorldPos;
+	vec3 vsNormal;
+	vec3 vsBiTangent;
+	vec3 vsTangent;
+	mat3 vsTBN;
+	flat uint vsChunkID;
+	flat uint vsMaterialID;
+}te_in[];
+
+layout (location=0) out TE_OUT
+{
+	vec2 vsUV;
+	vec4 vsWorldPos;
+	vec3 vsNormal;
+	vec3 vsBiTangent;
+	vec3 vsTangent;
+	mat3 vsTBN;
+	flat uint vsChunkID;
+	flat uint vsMaterialID;
+}te_out;
+
+void main()
+{
+    // get patch coordinate
+    te_out.vsUV.x = gl_TessCoord.x;
+    te_out.vsUV.y = gl_TessCoord.y;
+
+    // ----------------------------------------------------------------------
+    // retrieve control point texture coordinates
+    vec2 t00 = te_in[0].vsUV;
+    vec2 t01 = te_in[1].vsUV;
+    vec2 t10 = te_in[2].vsUV;
+    vec2 t11 = te_in[3].vsUV;
+
+//    t00|t10
+//    -------
+//    t10|t11
+
+    // ----------------------------------------------------------------------
+    // retrieve control point position coordinates
+    vec4 p00 = gl_in[0].gl_Position;
+    vec4 p01 = gl_in[1].gl_Position;
+    vec4 p10 = gl_in[2].gl_Position;
+    vec4 p11 = gl_in[3].gl_Position;
+
+    // compute patch surface normal
+    vec4 uVec = p01 - p00;
+    vec4 vVec = p10 - p00;
+    vec4 normal = normalize( vec4(cross(uVec.xyz, vVec.xyz), 1));
+
+    te_out.vsNormal = normal.xyz;
+    // bilinearly interpolate position coordinate across patch
+    vec4 p0 = (p01 - p00) *  te_out.vsUV.x + p00;
+    vec4 p1 = (p11 - p10) *  te_out.vsUV.x + p10;
+    vec4 p = (p1 - p0) *  te_out.vsUV.y + p0;
+    
+    // displace point along normal
+   // p += -normal * height;
+   //height = 0;
+    
+    //p[3] = 1;
+    // ----------------------------------------------------------------------
+    // output patch point position in clip space
+
+    mat4 model = model_matrix[te_in[0].vsChunkID];
+	mat4 view = ubo_per_frame.view;
+	mat4 proj = ubo_per_frame.proj;
+    gl_Position = proj * view * model * p;
+}