Merge pull request #72 from Legion2/scale-segments

Function to scale multiple parts of a strip independently

Author: Legion2

src/FastLEDControllerUtils.cpp

@@ -14,6 +14,7 @@
    limitations under the License.
 */
 #include "FastLEDControllerUtils.h"
+#include <math.h>
 
 void CLP::transformLLFanToStrip(FastLEDController* controller, uint8_t channelIndex)
 {
@@ -33,9 +34,9 @@ void CLP::transformLLFanToStrip(FastLEDController* controller, uint8_t channelIn
 void CLP::scale(FastLEDController* controller, uint8_t channelIndex, int scaleToSize)
 {
 	auto leds = controller->getLEDs(channelIndex);
-	float scaleFactor = (float)controller->getLEDCount(channelIndex) / scaleToSize;
+	const float scaleFactor = (float)controller->getLEDCount(channelIndex) / scaleToSize;
 	for (int ledIndex = scaleToSize - 1; ledIndex >= 0; ledIndex--) {
-		leds[ledIndex] = leds[(int)(ledIndex * scaleFactor)];
+		leds[ledIndex] = leds[round(ledIndex * scaleFactor)];
 	}
 }
 
@@ -48,3 +49,34 @@ void CLP::repeat(FastLEDController* controller, uint8_t channelIndex, uint8_t ti
 		memcpy(leds + (count * i), leds, sizeof(CRGB) * count);
 	}
 }
+
+void CLP::scaleSegments(FastLEDController* controller, uint8_t channelIndex, const SegmentScaling* const segments, int segmentsCount)
+{
+	auto leds = controller->getLEDs(channelIndex);
+	int ledStripIndexAfterScaling = 0;
+	int ledStripIndexBeforeScaling = 0;
+	for (int i = 0; i < segmentsCount; i++) {
+		ledStripIndexAfterScaling += segments[i].scaleToSize;
+		ledStripIndexBeforeScaling += segments[i].segmentLength;
+	}
+
+	for (int i = segmentsCount - 1; i >= 0; i--) {
+		const float scaleFactor = (float)segments[i].segmentLength / segments[i].scaleToSize;
+		ledStripIndexAfterScaling -= segments[i].scaleToSize;
+		ledStripIndexBeforeScaling -= segments[i].segmentLength;
+		for (int ledIndex = segments[i].scaleToSize - 1; ledIndex >= 0; ledIndex--) {
+			leds[ledStripIndexAfterScaling + ledIndex] = leds[ledStripIndexBeforeScaling + round(ledIndex * scaleFactor)];
+		}
+	}
+}
+
+void CLP::reverse(FastLEDController* controller, uint8_t channelIndex)
+{
+	auto leds = controller->getLEDs(channelIndex);
+	auto maxIndex = controller->getLEDCount(channelIndex) - 1;
+	for (int ledIndex = 0; ledIndex < maxIndex - ledIndex; ledIndex++) {
+		CRGB temp = leds[ledIndex];
+		leds[ledIndex] = leds[maxIndex - ledIndex];
+		leds[maxIndex - ledIndex] = temp;
+	}
+}

src/FastLEDControllerUtils.h

@@ -28,4 +28,36 @@ namespace CLP
 	void scale(FastLEDController* controller, uint8_t channelIndex, int scaleToSize);
 	//Repeat a channel's leds color to control more leds than provided by iCUE.
 	void repeat(FastLEDController* controller, uint8_t channelIndex, uint8_t times);
+
+	/**
+	 * Define the scaling information for a segment of a channel. A segment is a part of a channel that can be scale independently of other segments.
+	 */
+	struct SegmentScaling {
+		/**
+		 * The length of the segment in iCUE for example 10 for the normal LED strips
+		 */
+		int segmentLength;
+		/**
+		 * The size to which the segment will be scaled using Integer scaling
+		 */
+		int scaleToSize;
+	};
+	/**
+	 * Scales a channel's segments to given sizes. This can be used to apply different scaling factors to the different parts of a LED strip.
+	 * Integer scaling is used.
+	 * 
+	 * @param controller the FastLEDController controlling the LEDs
+	 * @param channelIndex the index of the channel you want to scale the segments on
+	 * @param segments the segments defining the size before and after scaling
+	 * @param segmentsCount the number of segments
+	 */
+	void scaleSegments(FastLEDController* controller, uint8_t channelIndex, const SegmentScaling* const segments, int segmentsCount);
+
+	/**
+	 * Reverse the LEDs of a channel, after this operation, the first led is the last and the last is the first.
+	 *
+	 * @param controller the FastLEDController controlling the LEDs
+	 * @param channelIndex the index of the channel you want to reverse
+	 */
+	void reverse(FastLEDController* controller, uint8_t channelIndex);
 }