From a0f579adf079f8583e23dfeba41d18749090fbdd Mon Sep 17 00:00:00 2001
From: Felix Pankratz <mail@felixpankratz.de>
Date: Wed, 25 Dec 2024 16:16:42 +0100
Subject: [PATCH] plasma

---
 nametag/src/enums.h    |  3 +-
 nametag/src/plasma.cpp | 68 ++++++++++++++++++++++++++++++++++++++++++
 nametag/src/plasma.h   |  3 ++
 3 files changed, 73 insertions(+), 1 deletion(-)
 create mode 100644 nametag/src/plasma.cpp
 create mode 100644 nametag/src/plasma.h

diff --git a/nametag/src/enums.h b/nametag/src/enums.h
index 9086da0..fb5eeba 100644
--- a/nametag/src/enums.h
+++ b/nametag/src/enums.h
@@ -10,6 +10,7 @@ enum DisplayStyle {
   Rain,
   Congress,
   Supercomputer,
-  Cyber
+  Cyber,
+  Plasma
 };
 #endif
diff --git a/nametag/src/plasma.cpp b/nametag/src/plasma.cpp
new file mode 100644
index 0000000..5b9f7c6
--- /dev/null
+++ b/nametag/src/plasma.cpp
@@ -0,0 +1,68 @@
+// https://lodev.org/cgtutor/plasma.html
+
+#include <Arduino.h>
+#include <FastLED.h>
+#include "constants.h"
+#include "enums.h"
+#include "plasma.h"
+
+#define dist(a, b, c, d) sqrt(double((a - c) * (a - c) + (b - d) * (b - d)))
+
+CRGB palette[256];
+int plasma[PANEL_HEIGHT][PANEL_WIDTH];
+bool plasma_ready = false;
+
+int palette_shift = 0;
+
+void setup_plasma() {
+  for(int i = 0; i < 256; i++) {
+
+    CHSV hsv_color(i, 255, 255);
+    hsv2rgb_rainbow(hsv_color, palette[i]);
+  }
+  // initial plasma
+  for(int y = 0; y < PANEL_HEIGHT; y++) {
+    for(int x = 0; x < PANEL_WIDTH; x++) {
+      //the plasma buffer is a sum of sines
+      int color = int
+      (
+          128.0 + (128.0 * sin(float(x) / 4.0))
+        + 128.0 + (128.0 * sin(float(y) / 2.0))
+        + 128.0 + (128.0 * sin(float(x + y) / 4.0))
+        + 128.0 + (128.0 * sin(sqrt(x * x + y * y) / 4.0))
+      ) / 4;
+      plasma[y][x] = color;
+    }
+  }
+  plasma_ready = true;
+}
+int timer = 0;
+void draw_plasma(MatrixPanel_I2S_DMA *matrix, Mode mode) {
+  //if (!plasma_ready)
+  //  setup_plasma();
+  //int timer = int(millis() / 25.0);
+  for (int y = 0; y < PANEL_HEIGHT; y++) {
+    for (int x = 0; x < PANEL_WIDTH; x++) {
+      //CRGB color = palette[(plasma[y][x] + palette_shift) % 256];
+      //double value = sin(dist(x + timer, y, 128.0, 128.0) / 8.0)
+      //       + sin(dist(x, y, 64.0, 64.0) / 8.0)
+      //       + sin(dist(x, y + timer / 7.0, 192.0, 64.0) / 7.0)
+      //       + sin(dist(x, y, 192.0, 100.0) / 8.0);
+      double value = (
+               sin(dist(x + timer, y, 128.0, 128.0) * 0.5)
+             + sin(dist(x, y, 64.0, 64.0) * 0.5)
+             + sin(dist(x, y + timer / 7.0, 192.0, 64.0)  * 0.5)
+             + sin(dist(x, y, 192.0, 100.0) * 0.5 )
+            ) * 0.25;
+      CRGB color;
+      CHSV hsv_color(int(128.0 + (value * 127.0)), 255, 255);
+      hsv2rgb_rainbow(hsv_color, color);
+      matrix->drawPixel(x, y, matrix->color565(color.r, color.g, color.b));
+      //if(Serial)
+      //  Serial.println(value);
+      //matrix->drawPixel(x, y, matrix->color565(color.r, color.g, color.b));
+    }
+  }
+  timer++;
+  //palette_shift++;
+}
diff --git a/nametag/src/plasma.h b/nametag/src/plasma.h
new file mode 100644
index 0000000..dec8fbf
--- /dev/null
+++ b/nametag/src/plasma.h
@@ -0,0 +1,3 @@
+#include <ESP32-HUB75-MatrixPanel-I2S-DMA.h>
+#include "enums.h"
+void draw_plasma(MatrixPanel_I2S_DMA *matrix, Mode mode);