generalized fp math pattern routines and added a psychedelic animation

animations/Makefile

@@ -53,8 +53,8 @@ ifeq ($(ANIMATION_LOGO_27C3),y)
   SRC += 27c3.c
 endif
 
-ifeq ($(ANIMATION_PLASMA),y)
-  SRC += plasma.c
+ifneq (,$(filter y,$(ANIMATION_PLASMA) $(ANIMATION_PSYCHEDELIC)))
+  SRC += fpmath_patterns.c
 endif
 
 include $(TOPDIR)/rules.mk

animations/config.in

@@ -22,6 +22,7 @@ comment "Animations"
 	endmenu
 
 	bool "Plasma"            ANIMATION_PLASMA
+	bool "Psychedelic"       ANIMATION_PSYCHEDELIC
 
 	comment  "Special Animations"
 	bool     "Test Animations"  ANIMATION_TESTS

animations/fpmath_patterns.c

@@ -0,0 +1,131 @@
+#include <math.h> // Floating point math is dog slow on AVR, but I don't care.
+#include <string.h>
+#include <stdint.h>
+#include "../config.h"
+#include "../pixel.h"
+#include "../util.h"
+#include "fpmath_patterns.h"
+
+#undef DOUBLE_BUFFERING
+#ifdef DOUBLE_BUFFERING
+#define BUFFER pixmap_buffer
+#else
+#define BUFFER pixmap
+#endif
+
+
+/**
+ * Pointer to a function which return a value depending on two-dimensional
+ * coordinates and a "step" value.
+ * @param x x-coordinate
+ * @param y y-coordinate
+ * @param t a step value which changes for each frame, allowing for animations
+ * @return
+ */
+typedef unsigned char (*fpmath_pattern_func_t)(unsigned char const x,
+                                               unsigned char const y,
+                                               double t);
+
+
+/**
+ * Calculates the distance between two points.
+ * @param x1 x coordinate of the first point
+ * @param y1 y coordinate of the first point
+ * @param x2 x coordinate of the second point
+ * @param y2 y coordinate of the second point
+ * @return distance between the points
+ */
+static double dist(double x1, double y1, double x2, double y2)
+{
+	return sqrt(((x1 - x2) * (x1 - x2)) + ((y1 - y2) * (y1 - y2)));
+}
+
+
+/**
+ * Draws an animated two dimensional graph for a given function f(x,y,t).
+ * @param t_start start value for the function's time variable
+ * @param t_stop stop value for the function's time variable
+ * @param t_delta value by which the functions timing variable gets incremented
+ * @param frame_delay frame delay in ms
+ * @param fpPattern function which generates a pattern depending x, y, t
+ */
+static void fpmath_pattern(double const t_start,
+                           double const t_stop,
+                           double const t_delta,
+                           unsigned int const frame_delay,
+                           fpmath_pattern_func_t fpPattern)
+{
+#ifdef DOUBLE_BUFFERING
+	// double buffering to reduce half painted pictures
+	unsigned char pixmap_buffer[NUMPLANE][NUM_ROWS][LINEBYTES];
+#endif
+	for (double t = t_start; t < t_stop; t += t_delta)
+	{
+		for (unsigned char y = 0; y < NUM_ROWS; ++y)
+		{
+			for (unsigned char x = 0; x < NUM_COLS; ++x)
+			{
+				unsigned char color = fpPattern(x, y, t);
+				for (uint8_t p = NUMPLANE; p--;)
+				{
+					if (p == (color - 1))
+					{
+						BUFFER[p][y][x / 8] |= shl_table[x % 8U];
+					}
+					else
+					{
+						BUFFER[p][y][x / 8] &= ~shl_table[x % 8U];
+					}
+				}
+			}
+		}
+#ifdef DOUBLE_BUFFERING
+		memcpy(pixmap, pixmap_buffer, sizeof(pixmap));
+#endif
+		wait(frame_delay);
+	}
+}
+
+
+#ifdef ANIMATION_PLASMA
+#define PLASMA_X (1.0 / (NUM_COLS / (2.0 * M_PI)))
+
+/**
+ * Draws a simple plasma like pattern.
+ */
+static unsigned char fpmath_plasma(unsigned char x, unsigned char y, double t)
+{
+	return (sin(x * PLASMA_X + t) + sin(dist(x, y, NUM_COLS * sin(t) + NUM_COLS,
+			NUM_ROWS * cos(t) + NUM_ROWS) * PLASMA_X) + 2) * (NUMPLANE - 1) / 2;
+}
+
+void plasma(void)
+{
+#ifndef __AVR__
+	fpmath_pattern(0.0, 75, 0.1, 80, fpmath_plasma);
+#else
+	fpmath_pattern(0.0, 60.0, 0.1, 1, fpmath_plasma);
+#endif
+}
+#endif
+
+
+#ifdef ANIMATION_PSYCHEDELIC
+/**
+ * Draws flowing circular waves with a rotating center.
+ */
+static unsigned char fpmath_psycho(unsigned char x, unsigned char y, double t)
+{
+	return (sin(dist(x, y, NUM_COLS * cos(t), NUM_ROWS * sin(t)) - t * 10) + 1)
+			* (NUMPLANE - 1);
+}
+
+void psychedelic(void)
+{
+#ifndef __AVR__
+	fpmath_pattern(0.0, 75, 0.1, 80, fpmath_psycho);
+#else
+	fpmath_pattern(0.0, 60.0, 0.1, 1, fpmath_psycho);
+#endif
+}
+#endif

animations/fpmath_patterns.h

@@ -0,0 +1,8 @@
+#ifndef FPMATH_PATTERNS_H_
+#define FPMATH_PATTERNS_H_
+
+void plasma(void);
+
+void psychedelic(void);
+
+#endif /* FPMATH_PATTERNS_H_ */

animations/plasma.c

@@ -1,54 +0,0 @@
-#include <math.h> // Floating point math is dog slow on AVR, but I don't care.
-#include <stdint.h>
-#include "../config.h"
-#include "../pixel.h"
-#include "../util.h"
-#include "plasma.h"
-
-
-#ifndef __AVR__
-	#define FRAME_TICK 80
-	#define FRAME_COUNT 750
-#else
-	#define FRAME_TICK 1
-	#define FRAME_COUNT 600
-#endif
-
-#define PLASMA_X (1.0 / (NUM_COLS / (2.0 * M_PI)))
-
-
-/**
- * calculates the distance between two points
- * @param x1 x coordinate of the first point
- * @param y1 y coordinate of the first point
- * @param x2 x coordinate of the second point
- * @param y2 y coordinate of the second point
- * @return distance between the points
- */
-static double dist(double x1, double y1, double x2, double y2)
-{
-	return sqrt(((x1 - x2) * (x1 - x2)) + ((y1 - y2) * (y1 - y2)));
-}
-
-
-/**
- * draws a simple plasma effect
- */
-void plasma(void)
-{
-	for (double t = 0; t < (FRAME_COUNT / 10.0); t = t + 0.1) {
-		for (unsigned char x = 0; x < NUM_COLS; ++x)
-		{
-			for (unsigned char y = 0; y < NUM_ROWS; ++y)
-			{
-				double nColor1 = sin(x * PLASMA_X + t) + 1;
-				double nColor2 = sin(dist(x, y,	NUM_COLS * sin(t) + NUM_COLS,
-					NUM_ROWS * cos(t) + NUM_ROWS) * PLASMA_X) + 1;
-				unsigned char nColor =
-						((nColor1 + nColor2) * (NUMPLANE - 1)) / 2;
-				setpixel((pixel){x, y}, nColor);
-			}
-		}
-		wait(FRAME_TICK);
-	}
-}

animations/plasma.h

@@ -1,6 +0,0 @@
-#ifndef PLASMA_H_
-#define PLASMA_H_
-
-void plasma(void);
-
-#endif /* PLASMA_H_ */

display_loop.c

@@ -16,6 +16,7 @@
 #include "animations/laborlogo.h"
 #include "animations/27c3.h"
 #include "animations/plasma.h"
+#include "animations/fpmath_patterns.h"
 #include "animations/mherweg.h"
 #include "borg_hw/borg_hw.h"
 #include "can/borg_can.h"
@@ -178,6 +179,12 @@ void display_loop(){
 			break;
 #endif
 
+#ifdef ANIMATION_PSYCHEDELIC
+		case 19:
+			psychedelic();
+			break;
+#endif
+
 
 #ifdef ANIMATION_TESTS
 		case 31: