feat: add curve inputs and raise uniform limit for GLSL shader node

[jtydhr88]

• Raise MAX_UNIFORMS from 5 to 20 for complex shaders
• Add bool uniform support (u_bool0-9)
• Add curve input support (u_curve0-3) as 256x1 1D LUT textures
• Mark GLSLShader as experimental
• Add Color Balance blueprint (GIMP-compatible shadows/midtones/highlights)

• Add Color Curves blueprint (GIMP-compatible per-channel + master curve)

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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Reviewing files that changed from the base of the PR and between c5c284e and ac4a0a9.

📒 Files selected for processing (1)

• comfy_extras/nodes_glsl.py

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📝 Walkthrough

Walkthrough

Adds two GLSL ES 3.00 fragment shaders: blueprints/.glsl/Color_Balance_15.frag (per-pixel shadows/midtones/highlights adjustments with optional luminosity preservation via RGB↔HSL) and blueprints/.glsl/Color_Curves_8.frag (per-channel + master 256-entry LUT curve mapping using texelFetch). Adds blueprint configurations blueprints/Color Balance.json and blueprints/Color Curves.json that wire those shaders into node graphs. Extends comfy_extras/nodes_glsl.py: increases uniform capacity (MAX_UNIFORMS→20), adds MAX_BOOLS and MAX_CURVES, adds bools and curves support, updates _render_shader_batch and GLSLShader.execute signatures, and implements GL setup/cleanup for curve LUT textures.

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 33.33% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately summarizes the main changes: raising uniform limits and adding curve/bool input support to the GLSL shader node.
Description check	✅ Passed	The description directly relates to the changeset, detailing the new uniforms, inputs, blueprints, and experimental status that are all present in the modifications.

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[coderabbitai]

Actionable comments posted: 2

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@comfy_extras/nodes_glsl.py`:
- Around line 881-885: The loop that builds curve_luts currently filters out
None entries causing sparse inputs to shift slots; in the block that iterates
over curves.values() (building curve_luts) preserve explicit slots by appending
a placeholder for None rather than skipping them — e.g., append None (or an
appropriately sized neutral LUT) when v is None so the indices of curve_luts
align with the original u_curve0/u_curve1/... slots; ensure the later GLSL
upload logic handles these None placeholders accordingly.
- Line 851: The tooltip for the curve input (io.Autogrow.Input with
template=curve_template) is misleading: update it to state that curves are 256×1
LUTs and recommend using texelFetch with manual linear interpolation as in the
built-in Color_Curves_8.frag (e.g., "Curves are available as
u_curve0-{MAX_CURVES-1} (sampler2D, 256×1 LUT). For accurate sampling, use
texelFetch with manual linear interpolation, as shown in the built-in
Color_Curves_8 shader."). In execute() (the curve binding/filtering loop) stop
silently compacting sparse curve lists: preserve original indices by either
padding missing entries with an identity LUT or binding textures explicitly to
their slot index (u_curveN) instead of using the filtered list position so that
curves[2] continues to map to u_curve2 even when curves[1] is None.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: ed94803f-6785-49e3-9e52-9b45a89df3a0

📥 Commits

Reviewing files that changed from the base of the PR and between 6580a6b and 74c021f.

📒 Files selected for processing (5)

• blueprints/.glsl/Color_Balance_15.frag
• blueprints/.glsl/Color_Curves_8.frag
• blueprints/Color Balance.json
• blueprints/Color Curves.json
• comfy_extras/nodes_glsl.py

[coderabbitai]

🧹 Nitpick comments (2)

comfy_extras/nodes_glsl.py (1)

90-92: Extract the curve LUT width into a shared constant.

256 is now part of the public contract in both the tooltip and to_lut(...). Naming it once will make future changes less error-prone.

♻️ Proposed cleanup

 MAX_UNIFORMS = 20   # u_float0-19, u_int0-19
 MAX_BOOLS = 10      # u_bool0-9
 MAX_CURVES = 4      # u_curve0-3 (1D LUT textures)
+CURVE_LUT_WIDTH = 256
 ...
-                io.Autogrow.Input("curves", template=curve_template, tooltip=f"Curves are available as u_curve0-{MAX_CURVES-1} (sampler2D, 256x1 LUT) in the shader code. Sample with texture(u_curve0, vec2(x, 0.5)).r"),
+                io.Autogrow.Input("curves", template=curve_template, tooltip=f"Curves are available as u_curve0-{MAX_CURVES-1} (sampler2D, {CURVE_LUT_WIDTH}x1 LUT) in the shader code. Sample with texture(u_curve0, vec2(x, 0.5)).r"),
 ...
-        curve_luts = [v.to_lut(256).astype(np.float32) for v in curves.values() if v is not None] if curves else []
+        curve_luts = [v.to_lut(CURVE_LUT_WIDTH).astype(np.float32) for v in curves.values() if v is not None] if curves else []

Also applies to: 850-851, 881-881

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@comfy_extras/nodes_glsl.py` around lines 90 - 92, Introduce a shared constant
(e.g., CURVE_LUT_WIDTH = 256) in comfy_extras/nodes_glsl.py and replace
hard-coded 256 occurrences in the curve tooltip text and any usages inside the
to_lut(...) implementation (and related spots around MAX_CURVES) with that
constant; update references where the LUT width is mentioned (tooltip strings
and function logic) to use CURVE_LUT_WIDTH so the value is centralized and
future changes are safe.

blueprints/.glsl/Color_Balance_15.frag (1)

17-17: Use the documented fragColor0 output pattern in the blueprint shader.

GLSLShader advertises layout(location = 0) out vec4 fragColor0; using the same form here makes this built-in shader a cleaner copy/paste example and keeps it aligned with the node’s output conventions.

♻️ Proposed cleanup

-out vec4 fragColor;
+layout(location = 0) out vec4 fragColor0;
...
-    fragColor = vec4(clamp(color, 0.0, 1.0), tex.a);
+    fragColor0 = vec4(clamp(color, 0.0, 1.0), tex.a);

Also applies to: 89-89

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@blueprints/.glsl/Color_Balance_15.frag` at line 17, The shader uses the
generic output symbol "out vec4 fragColor" but the project convention and
GLSLShader docs use "layout(location = 0) out vec4 fragColor0"; update the
fragment outputs (e.g., the declaration at "out vec4 fragColor" and the other
occurrence) to "layout(location = 0) out vec4 fragColor0" so the built-in shader
matches the node output convention and is copy/paste friendly with GLSLShader.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Nitpick comments:
In `@blueprints/.glsl/Color_Balance_15.frag`:
- Line 17: The shader uses the generic output symbol "out vec4 fragColor" but
the project convention and GLSLShader docs use "layout(location = 0) out vec4
fragColor0"; update the fragment outputs (e.g., the declaration at "out vec4
fragColor" and the other occurrence) to "layout(location = 0) out vec4
fragColor0" so the built-in shader matches the node output convention and is
copy/paste friendly with GLSLShader.

In `@comfy_extras/nodes_glsl.py`:
- Around line 90-92: Introduce a shared constant (e.g., CURVE_LUT_WIDTH = 256)
in comfy_extras/nodes_glsl.py and replace hard-coded 256 occurrences in the
curve tooltip text and any usages inside the to_lut(...) implementation (and
related spots around MAX_CURVES) with that constant; update references where the
LUT width is mentioned (tooltip strings and function logic) to use
CURVE_LUT_WIDTH so the value is centralized and future changes are safe.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: 55feba84-29ec-492c-9cbe-d57ffa0259f2

📥 Commits

Reviewing files that changed from the base of the PR and between 74c021f and c5c284e.

📒 Files selected for processing (5)

• blueprints/.glsl/Color_Balance_15.frag
• blueprints/.glsl/Color_Curves_8.frag
• blueprints/Color Balance.json
• blueprints/Color Curves.json
• comfy_extras/nodes_glsl.py

✅ Files skipped from review due to trivial changes (2)

• blueprints/Color Curves.json
• blueprints/Color Balance.json

🚧 Files skipped from review as they are similar to previous changes (1)

• blueprints/.glsl/Color_Curves_8.frag

[pythongosssss]

lgtm