Fix logz on lego plots in v7

Author: linev

scripts/JSRoot.v7gpad.js

@@ -513,6 +513,16 @@ JSROOT.define(['d3', 'painter'], (d3, jsrp) => {
       }
    }
 
+   /** @summary Return scale min */
+   RAxisPainter.prototype.getScaleMin = function() {
+      return this.func ? this.func.domain()[0] : 0;
+   }
+
+   /** @summary Return scale max */
+   RAxisPainter.prototype.getScaleMax = function() {
+      return this.func ? this.func.domain()[1] : 0;
+   }
+
    /** @summary Provide label for axis value */
    RAxisPainter.prototype.formatLabels = function(d) {
       let indx = Math.round(d);

scripts/JSRoot.v7hist3d.js

@@ -1001,8 +1001,8 @@ JSROOT.define(['d3', 'base3d', 'painter', 'latex', 'v7hist'], (d3, THREE, jsrp,
           // reduced vertices
           rvertices = [ new THREE.Vector3(0, 0, 0), new THREE.Vector3(0, 1, 0), new THREE.Vector3(1, 1, 0), new THREE.Vector3(1, 0, 0) ],
           main = this.getFramePainter(),
-          axis_zmin = main.z_handle.gr.domain()[0],
-          axis_zmax = main.z_handle.gr.domain()[1],
+          axis_zmin = main.z_handle.getScaleMin(),
+          axis_zmax = main.z_handle.getScaleMax(),
           zmin, zmax,
           handle = this.prepareDraw({ rounding: false, use3d: true, extra: 1 }),
           i1 = handle.i1, i2 = handle.i2, j1 = handle.j1, j2 = handle.j2, di = handle.stepi, dj = handle.stepj,
@@ -1524,7 +1524,7 @@ JSROOT.define(['d3', 'base3d', 'painter', 'latex', 'v7hist'], (d3, THREE, jsrp,
           i, j, x1, y1, x2, y2, z11, z12, z21, z22,
           di = handle.stepi, dj = handle.stepj,
           numstepi = handle.i2 - handle.i1, numstepj = handle.j2 - handle.j1,
-          axis_zmin = main.z_handle.gr.domain()[0];
+          axis_zmin = main.z_handle.getScaleMin();
 
       if (di > 1) {
          numstepi = Math.round(numstepi/di);
@@ -1945,8 +1945,8 @@ JSROOT.define(['d3', 'base3d', 'painter', 'latex', 'v7hist'], (d3, THREE, jsrp,
       let main = this.getFramePainter(),
           histo = this.getHisto(),
           handle = this.prepareDraw({ rounding: false, use3d: true, extra: 1 }),
-          zmin = main.z_handle.gr.domain()[0],
-          zmax = main.z_handle.gr.domain()[1],
+          zmin = main.z_handle.getScaleMin(),
+          zmax = main.z_handle.getScaleMax(),
           i, j, binz, binerr, x1, y1, x2, y2, z1, z2,
           nsegments = 0, lpos = null, binindx = null, lindx = 0,
           di = handle.stepi, dj = handle.stepj;
@@ -2054,8 +2054,8 @@ JSROOT.define(['d3', 'base3d', 'painter', 'latex', 'v7hist'], (d3, THREE, jsrp,
       let histo = this.getHisto(),
           palette = this.getHistPalette(),
           pmain = this.getFramePainter(),
-          axis_zmin = pmain.z_handle.gr.domain()[0],
-          axis_zmax = pmain.z_handle.gr.domain()[1],
+          axis_zmin = pmain.z_handle.getScaleMin(),
+          axis_zmax = pmain.z_handle.getScaleMax(),
           colindx, bin, i, len = histo.fBins.arr.length,
           z0 = pmain.grz(axis_zmin), z1;