glb -> PNG works, next is exercise for creating links to all glbs

exercises/create_png_from_glb/README.md

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+# Goal
+Create a PNG file from a glb (= glTF binary = Graphics Library Transmission Format https://en.wikipedia.org/wiki/GlTF).
+## Introduction
+This exercise will walk thorugh the creation of a PNG from the included glb.  The purpose is to show the steps taken to create the PNG which can be duplicated in a mass conversion script.
+
+You will be using the command console.
+
+The scripts run will create a small server; however, it will automatically select a port needed for the process so you do not have to be concerned of a port conflict, e.g. 3001, if you have another server running elsewhere on the system.  The kernel selects a currently unused high-numbered port (typically in the 32768–60999 range on Linux).
+
+## Prerequisites
+Node package: puppeteer
+
+## Steps
+Open a command console and change to the following subdirectory:
+
+     cd web/batch_glb_png/glbs
+
+for this exercise, create a soft link within glbs to just one file, we're only goint to perform a single PNG to demonstrate the scripts.  Normally, directory glbs will have links to the actual glbs staged (how those links are created is another exercise)
+
+     ln -s ../../'[o]_stealthburner_LED_carrier.stl.glb' .
+
+Example:
+
+     ~/work/Voron/voronstl/web/batch_glb_png/glbs $ ln -s ../../'[o]_stealthburner_LED_carrier.stl.glb' .
+
+Change to to the upper directory from within ```web/batch_glb_png``` and then launch the conversion script.  Note the run will use the job.json I created, when time comes when you want to use yours, then specify the path and filename to your PNG profile:
+
+    cd ../batch_glb_png
+    date;time node batch_render.js job.json
+
+Example:
+
+    jlpoole@jp ~/work/Voron/voronstl/web/batch_glb_png $ date;time node batch_render.js job.json
+    Wed Mar  4 18:17:13 PST 2026
+    PAGE console: error Failed to load resource: the server responded with a status of 404 (Not Found)
+    PAGE console: warn [.WebGL-0x7a40014ea00]GL Driver Message (OpenGL, Performance, GL_CLOSE_PATH_NV, High): GPU stall due to ReadPixels
+    PAGE console: warn [.WebGL-0x7a40014ea00]GL Driver Message (OpenGL, Performance, GL_CLOSE_PATH_NV, High): GPU stall due to ReadPixels
+    PAGE console: warn [.WebGL-0x7a40014ea00]GL Driver Message (OpenGL, Performance, GL_CLOSE_PATH_NV, High): GPU stall due to ReadPixels
+    WROTE   /home/jlpoole/work/Voron/voronstl/web/batch_glb_png/pngs/[o]_stealthburner_LED_carrier.stl.png
+
+    real    0m1.667s
+    user    0m1.327s
+    sys     0m0.423s
+    jlpoole@jp ~/work/Voron/voronstl/web/batch_glb_png $ 
+
+Result: a PNG 1227 × 994:
+![]([o]_stealthburner_LED_carrier.stl.png)
+
+# Conclusion
+Using the steps above, you created a single PNG from a glb.  
+
+The next step is to fill the glbs directory with links to the glbs perviously generated by Blender and then execute the same/similar command from within the '''web/batch_glb_png ''' directory:
+
+      node batch_render.js [your PNG specification, if you want]
+
+that will create a PNG for every glb.