4 files changed, 117 insertions, 0 deletions
diff --git a/themes/src/shaders/snowflake_frag.cpp b/themes/src/shaders/snowflake_frag.cpp
new file mode 100644
index 0000000..52d535d
--- /dev/null
+++ b/themes/src/shaders/snowflake_frag.cpp
@@ -0,0 +1,76 @@
+#include "snowflake_frag.h"
+
+const char* shader_snowflake_frag = "// Procedural star fragment shader \n"
+"varying lowp vec2 vUV; \n"
+"varying lowp float vSeed; \n"
+"varying lowp float vScale; \n"
+" \n"
+"const lowp float PI = 3.14159265359; \n"
+" \n"
+"// Simple hash function for deterministic randomness \n"
+"lowp float hash(lowp float n) { \n"
+"    return fract(sin(n) * 43758.5453123); \n"
+"} \n"
+" \n"
+"// Generate star pattern procedurally \n"
+"lowp float starPattern(lowp vec2 uv) { \n"
+"    lowp float dist = length(uv); \n"
+"    lowp float angle = atan(uv.y, uv.x); \n"
+" \n"
+"    // Number of star points (4 or 5) \n"
+"    lowp float numPoints = 4.0 + floor(hash(vSeed) * 2.0); \n"
+" \n"
+"    // Create sharp star with triangular points \n"
+"    lowp float angleStep = 2.0 * PI / numPoints; \n"
+"    lowp float currentAngle = mod(angle + PI / numPoints, angleStep) - angleStep * 0.5; \n"
+" \n"
+"    // Create triangular points - distance from center to edge varies linearly with angle \n"
+"    lowp float normalizedAngle = abs(currentAngle) / (angleStep * 0.5); \n"
+" \n"
+"    // Outer tip radius and inner valley radius \n"
+"    lowp float tipRadius = 0.5; \n"
+"    lowp float valleyRadius = 0.15; \n"
+" \n"
+"    // Linear interpolation creates sharp triangular points \n"
+"    lowp float rayEdge = mix(tipRadius, valleyRadius, normalizedAngle); \n"
+" \n"
+"    // Hard cutoff for sharp edges \n"
+"    lowp float star = step(dist, rayEdge); \n"
+" \n"
+"    return star; \n"
+"} \n"
+" \n"
+"void main() { \n"
+"    lowp float pattern = starPattern(vUV); \n"
+" \n"
+"    // Color variation based on seed - white and blue tints \n"
+"    lowp float colorVar = hash(vSeed * 3.0); \n"
+"    lowp vec3 starColor; \n"
+" \n"
+"    if (colorVar < 0.5) { \n"
+"        // Pure white \n"
+"        starColor = vec3(1.0, 1.0, 1.0); \n"
+"    } else if (colorVar < 0.75) { \n"
+"        // Light blue tint \n"
+"        starColor = vec3(0.9, 0.95, 1.0); \n"
+"    } else { \n"
+"        // Stronger blue tint \n"
+"        starColor = vec3(0.85, 0.92, 1.0); \n"
+"    } \n"
+" \n"
+"    // Scale alpha based on size - smaller stars are more transparent \n"
+"    // Normalize scale from range [16, 48] to [0, 1] \n"
+"    lowp float sizeRatio = (vScale - 16.0) / (48.0 - 16.0); \n"
+"    // Map to alpha range [0.3, 1.0] - smaller stars at 30% opacity, larger at 100% \n"
+"    lowp float alpha = mix(0.3, 1.0, sizeRatio); \n"
+" \n"
+"    lowp vec4 color = vec4(starColor, pattern * alpha); \n"
+" \n"
+"    // Discard fully transparent pixels for performance \n"
+"    if (color.a < 0.01) { \n"
+"        discard; \n"
+"    } \n"
+" \n"
+"    gl_FragColor = color; \n"
+"} \n"
+" \n";
diff --git a/themes/src/shaders/snowflake_frag.h b/themes/src/shaders/snowflake_frag.h
new file mode 100644
index 0000000..b34328f
--- /dev/null
+++ b/themes/src/shaders/snowflake_frag.h
@@ -0,0 +1,4 @@
+#ifndef SHADER_SNOWFLAKE_FRAG 
+#define SHADER_SNOWFLAKE_FRAG 
+extern const char* shader_snowflake_frag;
+#endif
diff --git a/themes/src/shaders/snowflake_vert.cpp b/themes/src/shaders/snowflake_vert.cpp
new file mode 100644
index 0000000..199009d
--- /dev/null
+++ b/themes/src/shaders/snowflake_vert.cpp
@@ -0,0 +1,33 @@
+#include "snowflake_vert.h"
+
+const char* shader_snowflake_vert = "// Instanced snowflake vertex shader \n"
+"attribute vec2 position;        // Base quad vertex position \n"
+"attribute vec2 instancePos;     // Per-instance: snowflake center position \n"
+"attribute float instanceRot;    // Per-instance: rotation angle \n"
+"attribute float instanceScale;  // Per-instance: size scale \n"
+"attribute float instanceSeed;   // Per-instance: random seed for variation \n"
+" \n"
+"uniform mat4 projection; \n"
+"uniform mat4 model; \n"
+" \n"
+"varying lowp vec2 vUV;           // UV coordinates for fragment shader \n"
+"varying lowp float vSeed;        // Pass seed to fragment shader \n"
+"varying lowp float vScale;       // Pass scale to fragment shader \n"
+" \n"
+"void main() { \n"
+"    // Rotate and scale the base quad \n"
+"    float c = cos(instanceRot); \n"
+"    float s = sin(instanceRot); \n"
+"    mat2 rotation = mat2(c, s, -s, c); \n"
+" \n"
+"    vec2 rotatedPos = rotation * (position * instanceScale); \n"
+"    vec2 worldPos = instancePos + rotatedPos; \n"
+" \n"
+"    gl_Position = projection * model * vec4(worldPos, 0.0, 1.0); \n"
+" \n"
+"    // Pass UV in range [-1, 1] for procedural generation \n"
+"    vUV = position; \n"
+"    vSeed = instanceSeed; \n"
+"    vScale = instanceScale; \n"
+"} \n"
+" \n";
diff --git a/themes/src/shaders/snowflake_vert.h b/themes/src/shaders/snowflake_vert.h
new file mode 100644
index 0000000..36bf8b0
--- /dev/null
+++ b/themes/src/shaders/snowflake_vert.h
@@ -0,0 +1,4 @@
+#ifndef SHADER_SNOWFLAKE_VERT 
+#define SHADER_SNOWFLAKE_VERT 
+extern const char* shader_snowflake_vert;
+#endif