Meshroom to Blender Low-Poly - Clean up photogrammetry Tutorial

good day to you today we're going to be exploring how to convert a messy high poly photogrammetry mushroom model into a clean but detailed low poly game ready asset for blender objects scan straight into meshroom present three major issues for 3d modelers they can be extremely dense and therefore high in file size and no good as game assets secondly these meshes are normally messy and inconsistent in density and quite often have gaping holes thirdly mushroom scans produce very disorganized texture maps making the process of editing the photo texture near on impossible during this tutorial i will show you how to get around each of these hurdles and produce clean low poly models as good as any top game development studio before we start make sure you have mushroom instant mesh and blender installed links for each of these can be found in the description below the process is quite straightforward let's walk through it now we will be compiling the model in mushroom importing and straightening it up in blender exporting it to instant mesh importing the low poly version back into blender repairing the low poly version unwrapping the low poly version and finally baking the textures and normal maps from the high to the low poly version [Music] [Applause] start by compiling your model in mushroom once it is finished processing import the newly generated obj model into blender by going to file import wavefront obj and navigate to where you've saved your meshroom project now go to meshroom cache texturing open the folder within texturing and import textured mesh obj the model is now in blender but you will need to straighten it up click three on the numeric pad for right view now press r and use your mouse to rotate the model until it is squared up click 1 for front view and rotate your model again until it is sitting flat click 7 for top view and rotate again if needed you may also want to repeat this process but this time using g to grab and reposition your object now that your model is positioned correctly let's take a look at it in wireframe view as you can see the mesh is a mess in areas there are holes with a mixture of large and small faces and there are regions that should be removed from this model let's keep things organized rename your object by double clicking here and typing in high res next ensure that we have the model selected let's export it by going to file export wavefront obj make sure you have limit 2 selected only checked export your obj model now load up instant mesh import your obj model for 2k models suitable for gaming bring this number down to 2k click on solve under orientation field and use the orientation comb to cause the mesh to curve around your object this will help later when unwrapping it for texturing click on solve beneath position field then click on export mesh under mesh settings check pure quad mesh with smoothing iterations of one then click extract mesh and then save your model i will rename it as low res import your low res obj back into blender and rename it i will call mine low-res for now i will hide the hi-res version go into solid viewport shading and press the tab key to take you into edit mode with edge select selected ensure that all of the mesh is selected by pressing the a key until the mesh turns orange right click and choose clear sharp now tab out of edit mode right click and choose shade smooth if you haven't already done so enable the high res and make sure that that model has also shade smooth enabled go back to your low res mesh and remove any parts of the model that you don't wish to use don't change its shape scale or add to the mesh just yet we can do that at the end of the process next we need to unwrap the mesh ready for texturing in order to do this we need to mark seams for an optimized unwrapping mark your seams mostly in areas that are not easily seen some seams will have to be in prominent areas tab into edit mode and using the edge select select where you want your seams to go and then right click and choose mark seams now in face select mode press a to select all and then u to bring up the unwrap options select unwrap now click on the uv editing tab to see the unwrapped uvs they should look clean like these we will now need to generate a texture for our low res model tapping out of edit mode as you can see from the material preview the high res has a photographic shader texture but the low res hasn't with the low res model selected click on the material property to ensure that the shader is already in place for this model if not add one rename your material now go over to the shading tab and click on the shading editor screen and hold down the shift key and press a and then s and type in image select image texture and hit return and then click to drop it here click new and type in 10 24 for 1k 2048 for 2k and 1496 for 4k textures click ok and connect your image texture to the base color your model should now look black as there is no image texture currently in place before you move on to the next stage double check that your image texture box is currently selected now enable your hi-res model select your hi-res mesh first and holding down the control key select your low res mesh now both are selected you must do it in this order open the render properties and select cycles as your render engine under sampling reduce your render to 8. under light paths maximum bounce the total should be 2 under light paths caustics switch off reflective and refractive under performance tiles select an x and y tile size that is the same as your image texture size now go down to bake and check selected to active with an extrusion of 0.1 we are going to bake the image texture first so select diffuse and then uncheck contributions direct and indirect click bake before moving on ensure your new image texture is saved now let's bake the details from the high res model as a normal map for our low poly model click anywhere in the shader editor and press shift a s and type in image select the image texture node new and ensure it has the same dimensions as the diffuse texture click on ok with the new image texture node selected change your bake type to normal and click bake save your new image texture now go to the shader editor and press shift a s and normal to find a normal map put it between your normal image texture and your principal shader connect the color of your image texture to the color of your normal map node and the normal to the normal ensure that your image texture has a color space of non color now hide the high res model all done as you can see if i disconnect both the normal map and the diffuse map and reintroduce the normal map the normal map has retained all of the detail from the high res version i can now further improve the mesh cleaning up any parts that i don't want fill in holes and tweak the model i then recommend using the clone tool on both the diffuse and normal maps that you have just generated to fix any missing regions within your photographic material [Music] [Applause] if you enjoyed this video don't forget to hit the like subscribe and if you've already subscribed hit the notification bell for more videos like this and i'd love to have a natter with you in the comments section thanks for joining me and i'll see you on the next one

Channel: Blender Bones

Views: 3,508

Keywords: import meshroom to blender, meshroom export to blender, photogrammetry, clean up photogrammetry, clean up photogrammetry blender, clean up scan blender, clean up 3d scan in blender, meshroom, blender

Id: -dc4KN2bdrw

Length: 8min 45sec (525 seconds)

Published: Thu Jul 01 2021