Add initial prototype.

3-mid/physics/implement/box2d/contrib/docs/images/tunneling2.svg

@@ -0,0 +1,140 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+
+<svg
+   xmlns:dc="http://purl.org/dc/elements/1.1/"
+   xmlns:cc="http://creativecommons.org/ns#"
+   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   width="234"
+   height="101.75"
+   id="svg2"
+   version="1.1"
+   inkscape:version="0.92.4 (5da689c313, 2019-01-14)"
+   sodipodi:docname="tunneling2.svg"
+   inkscape:export-filename="D:\Development\Box2D\Box2D\Documentation\images\tunneling.png"
+   inkscape:export-xdpi="90"
+   inkscape:export-ydpi="90">
+  <defs
+     id="defs4">
+    <marker
+       inkscape:stockid="Arrow2Mend"
+       orient="auto"
+       refY="0"
+       refX="0"
+       id="Arrow2Mend"
+       style="overflow:visible">
+      <path
+         id="path3648"
+         style="font-size:12px;fill-rule:evenodd;stroke-width:0.625;stroke-linejoin:round"
+         d="M 8.7185878,4.0337352 -2.2072895,0.01601326 8.7185884,-4.0017078 c -1.7454984,2.3720609 -1.7354408,5.6174519 -6e-7,8.035443 z"
+         transform="scale(-0.6)"
+         inkscape:connector-curvature="0" />
+    </marker>
+    <inkscape:perspective
+       sodipodi:type="inkscape:persp3d"
+       inkscape:vp_x="0 : 526.18109 : 1"
+       inkscape:vp_y="0 : 1000 : 0"
+       inkscape:vp_z="744.09448 : 526.18109 : 1"
+       inkscape:persp3d-origin="372.04724 : 350.78739 : 1"
+       id="perspective10" />
+    <inkscape:perspective
+       id="perspective3602"
+       inkscape:persp3d-origin="0.5 : 0.33333333 : 1"
+       inkscape:vp_z="1 : 0.5 : 1"
+       inkscape:vp_y="0 : 1000 : 0"
+       inkscape:vp_x="0 : 0.5 : 1"
+       sodipodi:type="inkscape:persp3d" />
+  </defs>
+  <sodipodi:namedview
+     id="base"
+     pagecolor="#ffffff"
+     bordercolor="#666666"
+     borderopacity="1.0"
+     inkscape:pageopacity="0.0"
+     inkscape:pageshadow="2"
+     inkscape:zoom="2"
+     inkscape:cx="-68"
+     inkscape:cy="83.750001"
+     inkscape:document-units="px"
+     inkscape:current-layer="layer1"
+     showgrid="false"
+     inkscape:window-width="1390"
+     inkscape:window-height="1038"
+     inkscape:window-x="50"
+     inkscape:window-y="50"
+     inkscape:window-maximized="0"
+     fit-margin-top="0"
+     fit-margin-left="0"
+     fit-margin-right="0"
+     fit-margin-bottom="0" />
+  <metadata
+     id="metadata7">
+    <rdf:RDF>
+      <cc:Work
+         rdf:about="">
+        <dc:format>image/svg+xml</dc:format>
+        <dc:type
+           rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
+        <dc:title></dc:title>
+      </cc:Work>
+    </rdf:RDF>
+  </metadata>
+  <g
+     inkscape:label="Layer 1"
+     inkscape:groupmode="layer"
+     id="layer1"
+     transform="translate(-210,-490.36218)">
+    <rect
+       style="fill:none;stroke:#000000;stroke-width:1;stroke-miterlimit:4;stroke-dasharray:none;stroke-dashoffset:0;stroke-opacity:1"
+       id="rect2816"
+       width="233"
+       height="13.5"
+       x="210.5"
+       y="541.86218" />
+    <circle
+       style="fill:none;stroke:#000000;stroke-width:1;stroke-miterlimit:4;stroke-dasharray:none;stroke-dashoffset:0;stroke-opacity:1"
+       id="path3592"
+       transform="translate(7.5,3)"
+       cx="295.25"
+       cy="494.11218"
+       r="6.25" />
+    <circle
+       style="fill:none;stroke:#000000;stroke-width:1;stroke-miterlimit:4;stroke-dasharray:none;stroke-dashoffset:0;stroke-opacity:1"
+       id="path3592-1"
+       transform="translate(7.5,91.25)"
+       cx="295.25"
+       cy="494.11218"
+       r="6.25" />
+    <path
+       style="fill:none;stroke:#000000;stroke-width:0.93691868;stroke-linecap:butt;stroke-linejoin:miter;stroke-miterlimit:4;stroke-dasharray:0.93691866, 1.87383732;stroke-dashoffset:0;stroke-opacity:1;marker-end:url(#Arrow2Mend)"
+       d="M 302.99984,505.33064 V 577.0062"
+       id="path3616"
+       inkscape:connector-curvature="0" />
+    <text
+       xml:space="preserve"
+       style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;line-height:0%;font-family:Calibri;-inkscape-font-specification:Calibri;text-align:start;writing-mode:lr-tb;text-anchor:start;fill:#000000;fill-opacity:1;stroke:none"
+       x="319"
+       y="499.86218"
+       id="text4066"><tspan
+         sodipodi:role="line"
+         id="tspan4068"
+         x="319"
+         y="499.86218"
+         style="font-size:12px;line-height:1.25">t=0</tspan></text>
+    <text
+       id="text4070"
+       y="587.86218"
+       x="319"
+       style="font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;line-height:0%;font-family:Calibri;-inkscape-font-specification:Calibri;text-align:start;writing-mode:lr-tb;text-anchor:start;fill:#000000;fill-opacity:1;stroke:none"
+       xml:space="preserve"><tspan
+         sodipodi:role="line"
+         id="tspan4074"
+         x="319"
+         y="587.86218"
+         style="font-size:12px;line-height:1.25">t=1</tspan></text>
+  </g>
+</svg>