lab2 Yi Liu

README.md

@@ -1,19 +1,60 @@
 # lab02-debugging
 
+Yi Liu 
+
 # Setup 
 
 Create a [Shadertoy account](https://www.shadertoy.com/). Either fork this shadertoy, or create a new shadertoy and copy the code from the [Debugging Puzzle](https://www.shadertoy.com/view/flGfRc).
 
-Let's practice debugging! We have a broken shader. It should produce output that looks like this:
-[Unbelievably beautiful shader](https://user-images.githubusercontent.com/1758825/200729570-8e10a37a-345d-4aff-8eff-6baf54a32a40.webm)
 
-It don't do that. Correct THREE of the FIVE bugs that are messing up the output. You are STRONGLY ENCOURAGED to work with a partner and pair program to force you to talk about your debugging thought process out loud.
+# Shader Link 
+https://www.shadertoy.com/view/M3fcD2
+
+
+<p align="center">
+  <img src="https://github.com/yiliu1237/lab02-debugging/blob/main/shader_result.gif?raw=true"/>
+</p>
+
+
+
+## Bug1: Syntax Error 
+- Issue: The variable uv2 was declared as vec instead of vec2.
+- Fix: Change the type of uv2 to vec2.
+- How It Was Found: The Shadertoy editor highlighted this as a syntax error upon running the shader.
+
+## Bug2: Incorrect Input to raycast Function
+- Issue: The uv variable was incorrectly used when calling the raycast function.
+- Fix: Use uv2 instead of uv when calling raycast to ensure proper coordinates are passed.
+- How It Was Found: The rendered output was distorted, leading to inspection of how coordinates were handled.
+
+## Bug3: Reflection Calculation Error
+- Issue: The reflection was not computed correctly due to the misuse of the reflect function.
+- Fix: Update the reflect function call to use the correct vector inputs:
+
+```
+dir = reflect(dir, nor);
+```
+
+- How It Was Found: The reflection on objects appeared incorrect, leading a deeper look into the reflection calculation. 
+
+## Bug4: Scene Aspect Ratio Distortion
+- Issue: The rendered scene was stretched along the x-axis, showing ellipsoids instead of spheres.
+- Fix: Adjust the scene's aspect ratio to prevent distortion.
+
+```
+uv2.x *= iResolution.x; 
+uv2.x /= iResolution.y;
+```
+
+- How It Was Found: Comparing the reference Shadertoy to the current output revealed the ratio issue.
+
+
+## Bug5: Insufficient Iterations in march Function
+- Issue: The march function was not iterating through enough steps, causing the scene to render incorrectly.
+- Fix: Increase the number of iterations in the march function to allow sufficient steps for ray marching:
 
-Extra credit if you can find all FIVE bugs.
+```
+for (int i = 0; i < 300; ++i) { ... }
+```
 
-# Submission
-- Create a pull request to this repository
-- In the README, include the names of both your team members
-- In the README, create a link to your shader toy solution with the bugs corrected
-- In the README, describe each bug you found and include a sentence about HOW you found it.
-- Make sure all three of your shadertoys are set to UNLISTED or PUBLIC (so we can see them!)
+- How It Was Found: Visual artifacts and incomplete rendering prompted the inspection of the march funtion.