Extended MatrixEffect to also get RainbowMatrixEffect and RandomMatrixEffect.

Side note: You know you understand C++ when you understand the meaning 
and reason for "MatrixEffect** _columns". ;-)

include/effect_matrix.h

@@ -1,5 +1,4 @@
-#ifndef effect_matrix_H
-#define effect_matrix_H
+#pragma once
 
 #include "prototypes.h"
 #include "Effect.h"
@@ -8,10 +7,12 @@
 #include "my_color_palettes.h"
 
 class MatrixEffectColumn {
-private:
-    int x, y;
-    int length;
+protected:
     Window* window;
+    int x, y;
+    int length = 1;
+    virtual CRGB _getColor(uint8_t height);
+private:
     uint16_t speed;
     boolean running;
     unsigned long last_move = 0;
@@ -19,24 +20,47 @@ public:
     MatrixEffectColumn();
     MatrixEffectColumn(Window* win, int xPos);
 
-    void start();
-
+    virtual void start();
     void advance();
-
     void draw();
-
     void loop();
 };
 
+class RainbowMatrixEffectColumn : public MatrixEffectColumn {
+protected:
+    CRGB _getColor(uint8_t height) override;
+public:
+    RainbowMatrixEffectColumn() : MatrixEffectColumn() {};
+    RainbowMatrixEffectColumn(Window* win, int xPos) : MatrixEffectColumn(win, xPos) {};
+};
+
+class RandomMatrixEffectColumn : public MatrixEffectColumn {
+protected:
+    uint8_t _hue = 42;
+    CRGB _getColor(uint8_t height) override;
+public:
+    void start() override;
+    RandomMatrixEffectColumn() : MatrixEffectColumn() {};
+    RandomMatrixEffectColumn(Window* win, int xPos) : MatrixEffectColumn(win, xPos) {};
+};
+
 class MatrixEffect : public Effect {
-private:
-    MatrixEffectColumn* _columns;
+protected:
+    MatrixEffectColumn** _columns;
 public:
     boolean can_be_shown_with_clock();
-    void start();
+    virtual void start();
     void stop();
     MatrixEffect();
     void loop();
 };
 
-#endif
+class RainbowMatrixEffect : public MatrixEffect {
+public:
+    void start() override;
+};
+
+class RandomMatrixEffect : public MatrixEffect {
+public:
+    void start() override;
+};

src/effect_matrix.cpp

@@ -26,12 +26,7 @@ void MatrixEffectColumn::advance() {
 
 void MatrixEffectColumn::draw() {
     for(int i=0; i<length; i++) {
-    	CRGB color;
-        if (i==0) {
-        	color = CRGB(255, 255, 255);
-        } else {
-        	color = ColorFromPalette((CRGBPalette16)palette_matrix, 255 * (length - i) / length);
-        }
+        CRGB color = _getColor(i);
         window->setPixel(x, y-i, &color);
     }
 }
@@ -52,21 +47,79 @@ void MatrixEffectColumn::loop() {
     }
 }
 
+CRGB MatrixEffectColumn::_getColor(uint8_t i) {
+    CRGB color;
+    if (i==0) {
+        color = CRGB(255, 255, 255);
+    } else {
+        color = CHSV(83, 255, 255 * (length - i) / length);
+    }
+    return color;
+}
+
+CRGB RainbowMatrixEffectColumn::_getColor(uint8_t i) {
+    CRGB color;
+    if (i==0) {
+        color = CRGB(255, 255, 255);
+    } else {
+        color = CHSV(255 * x / window->width, 255, 255 * (length - i) / length);
+    }
+    return color;
+}
+
+CRGB RandomMatrixEffectColumn::_getColor(uint8_t i) {
+    CRGB color;
+    //Serial.print("RandomMatrixEffectColumn::_getColor, hue="); Serial.println(_hue);
+    if (i==0) {
+        color = CRGB(255, 255, 255);
+    } else {
+        color = CHSV(_hue, 255, 255 * (length - i) / length);
+    }
+    return color;
+}
+
+void RandomMatrixEffectColumn::start() {
+    MatrixEffectColumn::start();
+    _hue = random8();
+}
+
+
+
+
+
+
+
+
+
+
 boolean MatrixEffect::can_be_shown_with_clock() { return true; };
 
 MatrixEffect::MatrixEffect() {
 }
 
 void MatrixEffect::start() {
-	_columns = new MatrixEffectColumn[LED_WIDTH];
-	for (int i=0; i<LED_WIDTH; i++) _columns[i] = MatrixEffectColumn(window, i);
+	_columns = new MatrixEffectColumn* [window->width];
+	for (int i=0; i<window->width; i++) _columns[i] = new MatrixEffectColumn(window, i);
+}
+
+void RandomMatrixEffect::start() {
+	_columns = new MatrixEffectColumn* [window->width];
+	for (int i=0; i<window->width; i++) _columns[i] = new RandomMatrixEffectColumn(window, i);
+}
+
+void RainbowMatrixEffect::start() {
+	_columns = new MatrixEffectColumn* [window->width];
+	for (int i=0; i<window->width; i++) _columns[i] = new RainbowMatrixEffectColumn(window, i);
 }
 
 void MatrixEffect::stop() {
+    for (int i=0; i<window->width; i++) {
+        delete _columns[i];
+    }
 	delete[] _columns;
 }
 
 void MatrixEffect::loop() {
     window->clear();
-    for (int i=0; i<window->width; i++) _columns[i].loop();
+    for (int i=0; i<window->width; i++) _columns[i]->loop();
 }

src/effects.cpp

@@ -35,6 +35,8 @@ AnimationEffect effect_anim_cake(&animation_cake, new CRGB(0x000000), 0, 0);
 SingleDynamicEffect effect_single_dynamic;
 MultiDynamicEffect effect_multi_dynamic;
 MatrixEffect effect_matrix;
+RandomMatrixEffect effect_random_matrix;
+RainbowMatrixEffect effect_rainbow_matrix;
 CycleEffect effect_cycle;
 TwirlEffect effect_twirl;
 ConfettiEffect effect_confetti;
@@ -60,6 +62,8 @@ void setup_effects() {
 	effects->add((EffectEntry){"single_dynamic", (Effect *)&effect_single_dynamic});
 	effects->add((EffectEntry){"multi_dynamic", (Effect *)&effect_multi_dynamic});
 	effects->add((EffectEntry){"matrix", (Effect *)&effect_matrix});
+	effects->add((EffectEntry){"rainbow_matrix", (Effect *)&effect_rainbow_matrix});
+	effects->add((EffectEntry){"random_matrix", (Effect *)&effect_random_matrix});
 	effects->add((EffectEntry){"cycle", (Effect *)&effect_cycle});
 	effects->add((EffectEntry){"twirl", (Effect *)&effect_twirl});
 	effects->add((EffectEntry){"heart", (Effect*)&effect_anim_heart});