Mark v_treeIndex with flat

This uses `flat` to make the GPU not try to interpolate the value.
Interpolation may on some GPUs cause "variance" of the same TreeIndex over a fragment. Even though the 1, 2, and 3 vertex Tree index is equal.

viewer/packages/rendering/src/glsl/sector/instancedMesh.frag

@@ -13,7 +13,7 @@ uniform sampler2D matCapTexture;
 uniform vec2 treeIndexTextureSize;
 uniform int renderMode;
 
-in float v_treeIndex;
+flat in float v_treeIndex;
 in vec3 v_color;
 in vec3 v_viewPosition;
 

viewer/packages/rendering/src/glsl/sector/instancedMesh.vert

@@ -13,17 +13,17 @@ in mat4 a_instanceMatrix;
 in float a_treeIndex;
 in vec3 a_color;
 
-out float v_treeIndex;
+flat out float v_treeIndex;
 out vec3 v_color;
 out vec3 v_viewPosition;
 
 void main()
 {
     mat4 treeIndexWorldTransform = determineMatrixOverride(
-      a_treeIndex, 
-      treeIndexTextureSize, 
-      transformOverrideIndexTexture, 
-      transformOverrideTextureSize, 
+      a_treeIndex,
+      treeIndexTextureSize,
+      transformOverrideIndexTexture,
+      transformOverrideTextureSize,
       transformOverrideTexture
     );
 

viewer/packages/rendering/src/glsl/sector/mesh.frag

@@ -13,7 +13,7 @@ uniform sampler2D matCapTexture;
 uniform vec2 treeIndexTextureSize;
 uniform int renderMode;
 
-in float v_treeIndex;
+flat in float v_treeIndex;
 in vec3 v_color;
 in vec3 v_viewPosition;
 

viewer/packages/rendering/src/glsl/sector/mesh.vert

@@ -10,21 +10,21 @@ uniform sampler2D transformOverrideTexture;
 
 in vec3 position;
 in vec3 color;
-in float treeIndex; 
+in float treeIndex;
 
 out vec3 v_color;
-out float v_treeIndex;
+flat out float v_treeIndex;
 out vec3 v_viewPosition;
 
 void main() {
     v_color = color;
     v_treeIndex = treeIndex;
 
     mat4 treeIndexWorldTransform = determineMatrixOverride(
-      treeIndex, 
-      treeIndexTextureSize, 
-      transformOverrideIndexTexture, 
-      transformOverrideTextureSize, 
+      treeIndex,
+      treeIndexTextureSize,
+      transformOverrideIndexTexture,
+      transformOverrideTextureSize,
       transformOverrideTexture
     );
 

viewer/packages/rendering/src/glsl/sector/primitives/circle.frag

@@ -12,7 +12,7 @@ uniform sampler2D matCapTexture;
 uniform vec2 treeIndexTextureSize;
 uniform int renderMode;
 
-in float v_treeIndex;
+flat in float v_treeIndex;
 in vec2 v_xy;
 in vec3 v_color;
 in vec3 v_normal;
@@ -23,7 +23,7 @@ void main() {
     vec3 normal = normalize( v_normal );
     if (dist > 0.25)
       discard;
-      
+
     NodeAppearance appearance = determineNodeAppearance(colorDataTexture, treeIndexTextureSize, v_treeIndex);
     if (!determineVisibility(appearance, renderMode)) {
         discard;

viewer/packages/rendering/src/glsl/sector/primitives/circle.vert

@@ -19,18 +19,18 @@ in vec3 a_normal;
 out vec2 v_xy;
 out vec3 v_color;
 out vec3 v_normal;
-out float v_treeIndex;
+flat out float v_treeIndex;
 out vec3 vViewPosition;
 
 void main() {
     v_xy = vec2(position.x, position.y);
     v_treeIndex = a_treeIndex;
 
     mat4 treeIndexWorldTransform = determineMatrixOverride(
-      a_treeIndex, 
-      treeIndexTextureSize, 
-      transformOverrideIndexTexture, 
-      transformOverrideTextureSize, 
+      a_treeIndex,
+      treeIndexTextureSize,
+      transformOverrideIndexTexture,
+      transformOverrideTextureSize,
       transformOverrideTexture
     );
 

viewer/packages/rendering/src/glsl/sector/primitives/cone.frag

@@ -24,7 +24,7 @@ in float v_angle;
 in float v_arcAngle;
 in vec4 v_centerA;
 in vec4 v_V;
-in float v_treeIndex;
+flat in float v_treeIndex;
 in vec3 v_color;
 in vec3 v_normal;
 

viewer/packages/rendering/src/glsl/sector/primitives/cone.vert

@@ -25,7 +25,7 @@ in vec3 a_localXAxis;
 in float a_angle;
 in float a_arcAngle;
 
-out float v_treeIndex;
+flat out float v_treeIndex;
 // We pack the radii into w-components
 out vec4 v_centerB;
 // U, V, axis represent the 3x3 cone basis.
@@ -42,10 +42,10 @@ out vec3 v_normal;
 
 void main() {
     mat4 treeIndexWorldTransform = determineMatrixOverride(
-      a_treeIndex, 
-      treeIndexTextureSize, 
-      transformOverrideIndexTexture, 
-      transformOverrideTextureSize, 
+      a_treeIndex,
+      treeIndexTextureSize,
+      transformOverrideIndexTexture,
+      transformOverrideTextureSize,
       transformOverrideTexture
     );
 

viewer/packages/rendering/src/glsl/sector/primitives/eccentricCone.frag

@@ -23,7 +23,7 @@ in vec4 axis;
 in vec4 v_centerA;
 in vec4 v_centerB;
 in float height;
-in float v_treeIndex;
+flat in float v_treeIndex;
 in vec3 v_color;
 in vec3 v_normal;
 

viewer/packages/rendering/src/glsl/sector/primitives/eccentricCone.vert

@@ -22,7 +22,7 @@ in float a_radiusB;
 in vec3 a_normal;
 in vec3 a_color;
 
-out float v_treeIndex;
+flat out float v_treeIndex;
 // We pack the radii into w-components
 out vec4 v_centerA;
 out vec4 v_centerB;
@@ -39,10 +39,10 @@ out vec3 v_normal;
 void main() {
 
   mat4 treeIndexWorldTransform = determineMatrixOverride(
-      a_treeIndex, 
-      treeIndexTextureSize, 
-      transformOverrideIndexTexture, 
-      transformOverrideTextureSize, 
+      a_treeIndex,
+      treeIndexTextureSize,
+      transformOverrideIndexTexture,
+      transformOverrideTextureSize,
       transformOverrideTexture
     );
 

viewer/packages/rendering/src/glsl/sector/primitives/ellipsoidSegment.frag

@@ -22,7 +22,7 @@ in float height;
 in vec4 U;
 in vec4 V;
 in vec4 sphereNormal;
-in float v_treeIndex;
+flat in float v_treeIndex;
 in vec3 v_color;
 in vec3 v_normal;
 

viewer/packages/rendering/src/glsl/sector/primitives/ellipsoidSegment.vert

@@ -22,7 +22,7 @@ in float a_horizontalRadius;
 in float a_verticalRadius;
 in float a_height;
 
-out float v_treeIndex;
+flat out float v_treeIndex;
 // We pack vRadius as w-component of center
 out vec4 center;
 out float hRadius;
@@ -39,10 +39,10 @@ out vec3 v_normal;
 void main() {
 
     mat4 treeIndexWorldTransform = determineMatrixOverride(
-      a_treeIndex, 
-      treeIndexTextureSize, 
-      transformOverrideIndexTexture, 
-      transformOverrideTextureSize, 
+      a_treeIndex,
+      treeIndexTextureSize,
+      transformOverrideIndexTexture,
+      transformOverrideTextureSize,
       transformOverrideTexture
     );
 

viewer/packages/rendering/src/glsl/sector/primitives/generalCylinder.frag

@@ -29,7 +29,7 @@ in float v_arcAngle;
 in float v_surfacePointY;
 in vec4 v_planeA;
 in vec4 v_planeB;
-in float v_treeIndex;
+flat in float v_treeIndex;
 in vec3 v_color;
 in vec3 v_normal;
 
@@ -39,7 +39,7 @@ void main() {
         discard;
     }
 
-    vec4 color = determineColor(v_color, appearance);    
+    vec4 color = determineColor(v_color, appearance);
     vec3 normal = normalize( v_normal );
 
     float R1 = v_centerB.w;

viewer/packages/rendering/src/glsl/sector/primitives/generalCylinder.vert

@@ -27,7 +27,7 @@ in vec3 a_localXAxis;
 in float a_angle;
 in float a_arcAngle;
 
-out float v_treeIndex;
+flat out float v_treeIndex;
 // We pack the radii into w-components
 out vec4 v_centerB;
 // U, V, axis represent the 3x3 cone basis.
@@ -48,13 +48,13 @@ void main() {
     mat4 modelViewMatrix = viewMatrix * modelMatrix;
 
     mat4 treeIndexWorldTransform = determineMatrixOverride(
-      a_treeIndex, 
-      treeIndexTextureSize, 
-      transformOverrideIndexTexture, 
-      transformOverrideTextureSize, 
+      a_treeIndex,
+      treeIndexTextureSize,
+      transformOverrideIndexTexture,
+      transformOverrideTextureSize,
       transformOverrideTexture
     );
-    
+
     mat4 modelTransformOffset = inverseModelMatrix * treeIndexWorldTransform * modelMatrix;
 
     vec3 centerA = mul3(modelTransformOffset, a_centerA);

viewer/packages/rendering/src/glsl/sector/primitives/generalring.frag

@@ -17,7 +17,7 @@ in float v_oneMinusThicknessSqr;
 in vec2 v_xy;
 in float v_angle;
 in float v_arcAngle;
-in float v_treeIndex;
+flat in float v_treeIndex;
 in vec3 v_color;
 in vec3 v_normal;
 in vec3 vViewPosition;

viewer/packages/rendering/src/glsl/sector/primitives/generalring.vert

@@ -19,7 +19,7 @@ in float a_arcAngle;
 in float a_thickness;
 in vec3 a_normal;
 
-out float v_treeIndex;
+flat out float v_treeIndex;
 out float v_oneMinusThicknessSqr;
 out vec2 v_xy;
 out float v_angle;
@@ -36,10 +36,10 @@ void main() {
     v_arcAngle = a_arcAngle;
 
     mat4 treeIndexWorldTransform = determineMatrixOverride(
-      a_treeIndex, 
-      treeIndexTextureSize, 
-      transformOverrideIndexTexture, 
-      transformOverrideTextureSize, 
+      a_treeIndex,
+      treeIndexTextureSize,
+      transformOverrideIndexTexture,
+      transformOverrideTextureSize,
       transformOverrideTexture
     );
 

viewer/packages/rendering/src/glsl/sector/primitives/sphericalSegment.frag

@@ -22,7 +22,7 @@ in float height;
 in vec4 U;
 in vec4 V;
 in vec4 sphereNormal;
-in float v_treeIndex;
+flat in float v_treeIndex;
 in vec3 v_color;
 in vec3 v_normal;
 
@@ -32,7 +32,7 @@ void main() {
         discard;
     }
 
-    vec4 color = determineColor(v_color, appearance);    
+    vec4 color = determineColor(v_color, appearance);
     vec3 normal = normalize(sphereNormal.xyz);
 
     float vRadius = center.w;

viewer/packages/rendering/src/glsl/sector/primitives/sphericalSegment.vert

@@ -17,7 +17,7 @@ in float a_horizontalRadius;
 in float a_verticalRadius;
 in float a_height;
 
-out float v_treeIndex;
+flat out float v_treeIndex;
 // We pack vRadius as w-component of center
 out vec4 center;
 out float hRadius;

viewer/packages/rendering/src/glsl/sector/primitives/torusSegment.frag

@@ -12,7 +12,7 @@ uniform sampler2D matCapTexture;
 uniform vec2 treeIndexTextureSize;
 uniform int renderMode;
 
-in float v_treeIndex;
+flat in float v_treeIndex;
 in vec3 v_color;
 in vec3 v_normal;
 in vec3 vViewPosition;
@@ -26,7 +26,7 @@ void main() {
         discard;
     }
 
-    vec4 color = determineColor(v_color, appearance);    
+    vec4 color = determineColor(v_color, appearance);
     vec3 normal = normalize(v_normal);
     updateFragmentColor(renderMode, color, v_treeIndex, normal, gl_FragCoord.z, matCapTexture, GeometryType.Primitive);
 }

viewer/packages/rendering/src/glsl/sector/primitives/torusSegment.vert

@@ -18,7 +18,7 @@ in float a_arcAngle;
 in float a_radius;
 in float a_tubeRadius;
 
-out float v_treeIndex;
+flat out float v_treeIndex;
 out vec3 v_color;
 out vec3 v_normal;
 out vec3 vViewPosition;
@@ -36,13 +36,13 @@ void main() {
     pos3.z = a_tubeRadius * sin(phi);
 
     mat4 treeIndexWorldTransform = determineMatrixOverride(
-      a_treeIndex, 
-      treeIndexTextureSize, 
-      transformOverrideIndexTexture, 
-      transformOverrideTextureSize, 
+      a_treeIndex,
+      treeIndexTextureSize,
+      transformOverrideIndexTexture,
+      transformOverrideTextureSize,
       transformOverrideTexture
     );
-    
+
     vec3 transformed = (a_instanceMatrix * vec4(pos3, 1.0)).xyz;
 
     // Calculate normal vectors if we're not picking

viewer/packages/rendering/src/glsl/sector/primitives/trapezium.frag

@@ -12,7 +12,7 @@ uniform sampler2D matCapTexture;
 uniform vec2 treeIndexTextureSize;
 uniform int renderMode;
 
-in float v_treeIndex;
+flat in float v_treeIndex;
 in vec3 v_color;
 in vec3 v_normal;
 in vec3 vViewPosition;
@@ -26,7 +26,7 @@ void main() {
         discard;
     }
 
-    vec4 color = determineColor(v_color, appearance);    
+    vec4 color = determineColor(v_color, appearance);
     vec3 normal = normalize(v_normal);
     updateFragmentColor(renderMode, color, v_treeIndex, normal, gl_FragCoord.z, matCapTexture, GeometryType.Primitive);
 }