fixed marker color, fixed read-from-texture

src/mol-gl/shader/chunks/apply-marker-color.glsl

-float marker = vMarker * 256.0;
+float marker = vMarker * 255.0;
 if (marker > 0.1) {
-    if (mod(marker, 2.0) < 0.1) {
+    if (mod(marker, 2.0) > 0.1) {
         gl_FragColor.rgb = mix(uHighlightColor, gl_FragColor.rgb, 0.3);
     } else {
         gl_FragColor.rgb = mix(uSelectColor, gl_FragColor.rgb, 0.3);

src/mol-gl/shader/utils/read-from-texture.glsl

@@ -4,9 +4,12 @@
  * @author Alexander Rose <alexander.rose@weirdbyte.de>
  */
 
+float intDiv(float a, float b) { return float(int(a) / int(b)); }
+float intMod(float a, float b) { return a - b * float(int(a) / int(b)); }
+
 vec4 readFromTexture (const in sampler2D tex, const in float i, const in vec2 dim) {
-    float x = mod(i, dim.x);
-    float y = floor(i / dim.x);
+    float x = intMod(i, dim.x);
+    float y = floor(intDiv(i, dim.x));
     vec2 uv = (vec2(x, y) + 0.5) / dim;
     return texture2D(tex, uv);
 }

src/mol-gl/shader/utils/texture3d-from-2d-linear.glsl

@@ -5,20 +5,19 @@
  * @author Michael Krone <michael.krone@uni-tuebingen.de>
  */
 
-// TODO workaround due to some kind of GPU quirk
-float myMod(float a, float b) { return a - b * float(int(a) / int(b)); }
-float myDiv(float a, float b) { return float(int(a) / int(b)); }
+float intDiv(float a, float b) { return float(int(a) / int(b)); }
+float intMod(float a, float b) { return a - b * float(int(a) / int(b)); }
 
 vec4 texture3dFrom2dLinear(sampler2D tex, vec3 pos, vec3 gridDim, vec2 texDim) {
     float zSlice0 = floor(pos.z * gridDim.z);
-    float column0 = myMod(zSlice0 * gridDim.x, texDim.x) / gridDim.x;
-    float row0 = floor(myDiv(zSlice0 * gridDim.x, texDim.x));
+    float column0 = intMod(zSlice0 * gridDim.x, texDim.x) / gridDim.x;
+    float row0 = floor(intDiv(zSlice0 * gridDim.x, texDim.x));
     vec2 coord0 = (vec2(column0 * gridDim.x, row0 * gridDim.y) + (pos.xy * gridDim.xy)) / texDim;
     vec4 color0 = texture2D(tex, coord0);
 
     float zSlice1 = zSlice0 + 1.0;
-    float column1 = myMod(zSlice1 * gridDim.x, texDim.x) / gridDim.x;
-    float row1 = floor(myDiv(zSlice1 * gridDim.x, texDim.x));
+    float column1 = intMod(zSlice1 * gridDim.x, texDim.x) / gridDim.x;
+    float row1 = floor(intDiv(zSlice1 * gridDim.x, texDim.x));
     vec2 coord1 = (vec2(column1 * gridDim.x, row1 * gridDim.y) + (pos.xy * gridDim.xy)) / texDim;
     vec4 color1 = texture2D(tex, coord1);
 

src/mol-gl/shader/utils/texture3d-from-2d-nearest.glsl

@@ -5,14 +5,13 @@
  * @author Michael Krone <michael.krone@uni-tuebingen.de>
  */
 
-// TODO workaround due to some kind of GPU quirk
-float myMod(float a, float b) { return a - b * float(int(a) / int(b)); }
-float myDiv(float a, float b) { return float(int(a) / int(b)); }
+float intDiv(float a, float b) { return float(int(a) / int(b)); }
+float intMod(float a, float b) { return a - b * float(int(a) / int(b)); }
 
 vec4 texture3dFrom2dNearest(sampler2D tex, vec3 pos, vec3 gridDim, vec2 texDim) {
     float zSlice = floor(pos.z * gridDim.z + 0.5); // round to nearest z-slice
-    float column = myMod(zSlice * gridDim.x, texDim.x) / gridDim.x;
-    float row = floor(myDiv(zSlice * gridDim.x, texDim.x));
+    float column = intMod(zSlice * gridDim.x, texDim.x) / gridDim.x;
+    float row = floor(intDiv(zSlice * gridDim.x, texDim.x));
     vec2 coord = (vec2(column * gridDim.x, row * gridDim.y) + (pos.xy * gridDim.xy)) / texDim;
     return texture2D(tex, coord);
 }