Special: Collision makes disappear the object
18 January 2015 04:00
Hello,
I recently upgraded to Blender 2.72 and Blend4Web 14.12 and I am facing a problem I have never met before.
I made a very simple scene, a plane for the ground and a cube. And for the code I copied and simplified the one from "making_a_game_p1-3".
Following the manual for the physics engine, the plane is static and its material has "Special: Collision" enabled. The cube is set to rigid body.
When I open it in Firefox, the ground has disappeared however the cube which was somehow in the air falls as expected and is stopped by the ground.
So it works as expected physically speaking but visually the ground is invisible. If I disable "Special: Collision" the ground is viewable but of course the cube falls through it. Any hint ?
I can pack you the whole repository if needed.
I recently upgraded to Blender 2.72 and Blend4Web 14.12 and I am facing a problem I have never met before.
I made a very simple scene, a plane for the ground and a cube. And for the code I copied and simplified the one from "making_a_game_p1-3".
Following the manual for the physics engine, the plane is static and its material has "Special: Collision" enabled. The cube is set to rigid body.
When I open it in Firefox, the ground has disappeared however the cube which was somehow in the air falls as expected and is stopped by the ground.
So it works as expected physically speaking but visually the ground is invisible. If I disable "Special: Collision" the ground is viewable but of course the cube falls through it. Any hint ?
I can pack you the whole repository if needed.
18 January 2015 09:03
So you need to make a copy of your ground plane and assign a generic non-collision material to it. 
20 January 2015 02:40
It is indeed a little puzzling, specially from a BGE user perspective. I would like to understand.
This is a "recent" requirement to force a static object to have an explicit collision material to be taken in account by the physics system, isn't it ? I have another B4W project made with Blender 2.70 and version 14.05 of the SDK and I had not the need to set "Special: Collision" for the ground material, the objects were yet able to rebound on it.
What is the reason for this change, and why not let the exporter create automatically this copied object for instance ?
This is a "recent" requirement to force a static object to have an explicit collision material to be taken in account by the physics system, isn't it ? I have another B4W project made with Blender 2.70 and version 14.05 of the SDK and I had not the need to set "Special: Collision" for the ground material, the objects were yet able to rebound on it.
What is the reason for this change, and why not let the exporter create automatically this copied object for instance ?
20 January 2015 10:24
Hi,
Static collisions are really a subject to debate and recently we have made a decision to move to a Blender-like system when you don't need to copy original mesh and define special-collision material. So you can expect such a behavior in February with Blend4Web 15.02 release.
Static collisions are really a subject to debate and recently we have made a decision to move to a Blender-like system when you don't need to copy original mesh and define special-collision material. So you can expect such a behavior in February with Blend4Web 15.02 release.
I have another B4W project made with Blender 2.70 and version 14.05 of the SDK and I had not the need to set "Special: Collision" for the ground material, the objects were yet able to rebound on itProbably there was some kind of bug or a hidden material as we haven't been changing this behavior from the first release.
21 January 2015 10:31
This feature appeared to be more easy to realize. Thus it will appear in Blend4Web 15.01 next week.