Shader Programming Glsl

Shader Programming GLSL

Overview

This public intake copy packages plugins/antigravity-awesome-skills-claude/skills/shader-programming-glsl from https://github.com/sickn33/antigravity-awesome-skills into the native Omni Skills editorial shape without hiding its origin.

Use it when the operator needs the upstream workflow, support files, and repository context to stay intact while the public validator and private enhancer continue their normal downstream flow.

This intake keeps the copied upstream files intact and uses the external_source block in metadata.json plus ORIGIN.md as the provenance anchor for review.

Shader Programming GLSL

Imported source sections that did not map cleanly to the public headings are still preserved below or in the support files. Notable imported sections: Limitations.

When to Use This Skill

Use this section as the trigger filter. It should make the activation boundary explicit before the operator loads files, runs commands, or opens a pull request.

• Use when creating custom visual effects in WebGL, Three.js, or game engines.
• Use when optimizing graphics rendering performance.
• Use when implementing post-processing effects (blur, bloom, color correction).
• Use when procedurally generating textures or geometry on the GPU.
• Use when the request clearly matches the imported source intent: Expert guide for writing efficient GLSL shaders (Vertex/Fragment) for web and game engines, covering syntax, uniforms, and common effects.
• Use when the operator should preserve upstream workflow detail instead of rewriting the process from scratch.

Operating Table

Workflow

This workflow is intentionally editorial and operational at the same time. It keeps the imported source useful to the operator while still satisfying the public intake standards that feed the downstream enhancer flow.

1. Vertex Shader: Transforms 3D coordinates to 2D screen space (gl_Position).
2. Fragment Shader: Colors individual pixels (gl_FragColor).
3. uniform: Data constant for all vertices/fragments (passed from CPU).
4. varying: Data interpolated from vertex to fragment shader.
5. color.rgb -> vec3(1.0, 0.5, 0.0)
6. color.zyx -> vec3(0.0, 0.5, 1.0) (reordering)
7. Confirm the user goal, the scope of the imported workflow, and whether this skill is still the right router for the task.

Imported Workflow Notes

Imported: Step-by-Step Guide

1. Structure: Vertex vs. Fragment

Understand the pipeline:

• Vertex Shader: Transforms 3D coordinates to 2D screen space (gl_Position).
• Fragment Shader: Colors individual pixels (gl_FragColor).

// Vertex Shader (basic)
attribute vec3 position;
uniform mat4 modelViewMatrix;
uniform mat4 projectionMatrix;

void main() {
    gl_Position = projectionMatrix * modelViewMatrix * vec4(position, 1.0);
}

// Fragment Shader (basic)
uniform vec3 color;

void main() {
    gl_FragColor = vec4(color, 1.0);
}

2. Uniforms and Varyings

• uniform: Data constant for all vertices/fragments (passed from CPU).
• varying: Data interpolated from vertex to fragment shader.

// Passing UV coordinates
varying vec2 vUv;

// In Vertex Shader
void main() {
    vUv = uv;
    gl_Position = projectionMatrix * modelViewMatrix * vec4(position, 1.0);
}

// In Fragment Shader
void main() {
    // Gradient based on UV
    gl_FragColor = vec4(vUv.x, vUv.y, 1.0, 1.0);
}

3. Swizzling & Vector Math

Access vector components freely: vec4 color = vec4(1.0, 0.5, 0.0, 1.0);

• color.rgb -> vec3(1.0, 0.5, 0.0)
• color.zyx -> vec3(0.0, 0.5, 1.0) (reordering)

Imported: Overview

A comprehensive guide to writing GPU shaders using GLSL (OpenGL Shading Language). Learn syntax, uniforms, varying variables, and key mathematical concepts like swizzling and vector operations for visual effects.

Imported: Limitations

• Use this skill only when the task clearly matches the scope described above.
• Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
• Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.

Examples

Example 1: Ask for the upstream workflow directly

Use @shader-programming-glsl to handle <task>. Start from the copied upstream workflow, load only the files that change the outcome, and keep provenance visible in the answer.

Explanation: This is the safest starting point when the operator needs the imported workflow, but not the entire repository.

Example 2: Ask for a provenance-grounded review

Review @shader-programming-glsl against metadata.json and ORIGIN.md, then explain which copied upstream files you would load first and why.

Explanation: Use this before review or troubleshooting when you need a precise, auditable explanation of origin and file selection.

Example 3: Narrow the copied support files before execution

Use @shader-programming-glsl for <task>. Load only the copied references, examples, or scripts that change the outcome, and name the files explicitly before proceeding.

Explanation: This keeps the skill aligned with progressive disclosure instead of loading the whole copied package by default.

Example 4: Build a reviewer packet

Review @shader-programming-glsl using the copied upstream files plus provenance, then summarize any gaps before merge.

Explanation: This is useful when the PR is waiting for human review and you want a repeatable audit packet.

Imported Usage Notes

Imported: Examples

Example 1: Simple Raymarching (SDF Sphere)

float sdSphere(vec3 p, float s) {
    return length(p) - s;
}

void mainImage(out vec4 fragColor, in vec2 fragCoord) {
    vec2 uv = (fragCoord - 0.5 * iResolution.xy) / iResolution.y;
    vec3 ro = vec3(0.0, 0.0, -3.0); // Ray Origin
    vec3 rd = normalize(vec3(uv, 1.0)); // Ray Direction

    float t = 0.0;
    for(int i = 0; i < 64; i++) {
        vec3 p = ro + rd * t;
        float d = sdSphere(p, 1.0); // Sphere radius 1.0
        if(d < 0.001) break;
        t += d;
    }

    vec3 col = vec3(0.0);
    if(t < 10.0) {
        vec3 p = ro + rd * t;
        vec3 normal = normalize(p);
        col = normal * 0.5 + 0.5; // Color by normal
    }

    fragColor = vec4(col, 1.0);
}

Best Practices

Treat the generated public skill as a reviewable packaging layer around the upstream repository. The goal is to keep provenance explicit and load only the copied source material that materially improves execution.

• ✅ Do: Use mix() for linear interpolation instead of manual math.
• ✅ Do: Use step() and smoothstep() for thresholding and soft edges (avoid if branches).
• ✅ Do: Pack data into vectors (vec4) to minimize memory access.
• ❌ Don't: Use heavy branching (if-else) inside loops if possible; it hurts GPU parallelism.
• ❌ Don't: Calculate constant values inside the shader; pre-calculate them on the CPU (uniforms).
• Keep the imported skill grounded in the upstream repository; do not invent steps that the source material cannot support.
• Prefer the smallest useful set of support files so the workflow stays auditable and fast to review.

Imported Operating Notes

Imported: Best Practices

• ✅ Do: Use mix() for linear interpolation instead of manual math.
• ✅ Do: Use step() and smoothstep() for thresholding and soft edges (avoid if branches).
• ✅ Do: Pack data into vectors (vec4) to minimize memory access.
• ❌ Don't: Use heavy branching (if-else) inside loops if possible; it hurts GPU parallelism.
• ❌ Don't: Calculate constant values inside the shader; pre-calculate them on the CPU (uniforms).

Troubleshooting

Problem: The operator skipped the imported context and answered too generically

Symptoms: The result ignores the upstream workflow in plugins/antigravity-awesome-skills-claude/skills/shader-programming-glsl, fails to mention provenance, or does not use any copied source files at all. Solution: Re-open metadata.json, ORIGIN.md, and the most relevant copied upstream files. Check the external_source block first, then restate the provenance before continuing.

Problem: The imported workflow feels incomplete during review

Symptoms: Reviewers can see the generated SKILL.md, but they cannot quickly tell which references, examples, or scripts matter for the current task. Solution: Point at the exact copied references, examples, scripts, or assets that justify the path you took. If the gap is still real, record it in the PR instead of hiding it.

Problem: The task drifted into a different specialization

Symptoms: The imported skill starts in the right place, but the work turns into debugging, architecture, design, security, or release orchestration that a native skill handles better. Solution: Use the related skills section to hand off deliberately. Keep the imported provenance visible so the next skill inherits the right context instead of starting blind.

Imported Troubleshooting Notes

Imported: Troubleshooting

Problem: Shader compiles but screen is black. Solution: Check if gl_Position.w is correct (usually 1.0). Check if uniforms are actually being set from the host application. Verify UV coordinates are within [0, 1].

Related Skills

• @00-andruia-consultant - Use when the work is better handled by that native specialization after this imported skill establishes context.
• @00-andruia-consultant-v2 - Use when the work is better handled by that native specialization after this imported skill establishes context.
• @10-andruia-skill-smith - Use when the work is better handled by that native specialization after this imported skill establishes context.
• @10-andruia-skill-smith-v2 - Use when the work is better handled by that native specialization after this imported skill establishes context.

Additional Resources

Use this support matrix and the linked files below as the operator packet for this imported skill. They should reflect real copied source material, not generic scaffolding.