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// This file is part of the 64k demo project.
// It implements basic procedural texture generators.

#include "procedural/generator.h"
#include <cmath>
#include <cstdlib>

namespace procedural {

// Simple noise generator
// Params[0]: Seed (optional, if 0 uses rand())
// Params[1]: Intensity (0.0 - 1.0)
void gen_noise(uint8_t* buffer, int w, int h, const float* params,
               int num_params) {
  float intensity = (num_params > 1) ? params[1] : 1.0f;
  if (num_params > 0 && params[0] != 0) {
    srand((unsigned int)params[0]);
  }

  for (int i = 0; i < w * h; ++i) {
    uint8_t val = (uint8_t)((rand() % 255) * intensity);
    buffer[i * 4 + 0] = val; // R
    buffer[i * 4 + 1] = val; // G
    buffer[i * 4 + 2] = val; // B
    buffer[i * 4 + 3] = 255; // A
  }
}

// Simple grid generator
// Params[0]: Grid Size (pixels)
// Params[1]: Line Thickness (pixels)
void gen_grid(uint8_t* buffer, int w, int h, const float* params,
              int num_params) {
  int grid_size = (num_params > 0) ? (int)params[0] : 32;
  int thickness = (num_params > 1) ? (int)params[1] : 2;

  if (grid_size < 1)
    grid_size = 32;

  for (int y = 0; y < h; ++y) {
    for (int x = 0; x < w; ++x) {
      bool on_line = ((x % grid_size) < thickness) ||
                     ((y % grid_size) < thickness);

      int idx = (y * w + x) * 4;
      uint8_t val = on_line ? 255 : 0;

      buffer[idx + 0] = val;
      buffer[idx + 1] = val;
      buffer[idx + 2] = val;
      buffer[idx + 3] = 255;
    }
  }
}

} // namespace procedural