add xray shading edge fallof parameter

src/mol-gl/renderable/schema.ts

@@ -159,6 +159,8 @@ export const GlobalUniformSchema = {
     uHighlightColor: UniformSpec('v3'),
     uSelectColor: UniformSpec('v3'),
 
+    uXrayEdgeFalloff: UniformSpec('f'),
+
     uRenderWboit: UniformSpec('b'),
 } as const;
 export type GlobalUniformSchema = typeof GlobalUniformSchema

src/mol-gl/renderer.ts

@@ -77,6 +77,8 @@ export const RendererParams = {
     highlightColor: PD.Color(Color.fromNormalizedRgb(1.0, 0.4, 0.6)),
     selectColor: PD.Color(Color.fromNormalizedRgb(0.2, 1.0, 0.1)),
 
+    xrayEdgeFalloff: PD.Numeric(1, { min: 0.0, max: 3.0, step: 0.1 }),
+
     style: PD.MappedStatic('matte', {
         custom: PD.Group({
             lightIntensity: PD.Numeric(0.6, { min: 0.0, max: 1.0, step: 0.01 }),
@@ -257,6 +259,8 @@ namespace Renderer {
 
             uHighlightColor: ValueCell.create(Color.toVec3Normalized(Vec3(), p.highlightColor)),
             uSelectColor: ValueCell.create(Color.toVec3Normalized(Vec3(), p.selectColor)),
+
+            uXrayEdgeFalloff: ValueCell.create(p.xrayEdgeFalloff),
         };
         const globalUniformList = Object.entries(globalUniforms);
 
@@ -607,6 +611,11 @@ namespace Renderer {
                     ValueCell.update(globalUniforms.uSelectColor, Color.toVec3Normalized(globalUniforms.uSelectColor.ref.value, p.selectColor));
                 }
 
+                if (props.xrayEdgeFalloff !== undefined && props.xrayEdgeFalloff !== p.xrayEdgeFalloff) {
+                    p.xrayEdgeFalloff = props.xrayEdgeFalloff;
+                    ValueCell.update(globalUniforms.uXrayEdgeFalloff, p.xrayEdgeFalloff);
+                }
+
                 if (props.style !== undefined) {
                     p.style = props.style;
                     Object.assign(style, getStyle(props.style));

src/mol-gl/shader/chunks/apply-light-color.glsl.ts

@@ -49,6 +49,6 @@ vec3 outgoingLight = reflectedLight.directDiffuse + reflectedLight.indirectDiffu
 gl_FragColor = vec4(outgoingLight, color.a);
 
 #ifdef dXrayShaded
-    gl_FragColor.a *= 1.0 - max(0.001, abs(dot(normal, vec3(0, 0, 1))));
+    gl_FragColor.a *= 1.0 - pow(abs(dot(normal, vec3(0, 0, 1))), uXrayEdgeFalloff);
 #endif
 `;

src/mol-gl/shader/chunks/common-frag-params.glsl.ts

@@ -49,5 +49,7 @@ uniform bool uInteriorColorFlag;
 uniform vec3 uInteriorColor;
 bool interior;
 
+uniform float uXrayEdgeFalloff;
+
 uniform mat4 uProjection;
 `;