Finally fixed color-format from fb (RGB565).

README.md

@@ -2,5 +2,5 @@
 This repository contains all the software required to turn an old ceiling fan into a fully functional POV-display.
 
 ## Build Instructions
-To build, use `$ gcc -o pov -lpthread -lm main.c spi.c pov.c`.
+To build, use `$ gcc -pthread -o pov -lm main.c spi.c pov.c -lm`.
 And then `$./pov` to run the application.
\ No newline at end of file

pov.c

@@ -66,6 +66,7 @@ static int set_wing_led_color(volatile led_wing *wing, int led, uint8_t r, uint8
 static void get_xy_from_rt(int *x, int *y, int r, int t){
     *x = (int)((float)r * cos(t)) + var_info.xres / 2;
     *y = (int)((float)r * sin(t)) + var_info.yres / 2;
+    //printf("x: %d, y: %d, r: %d, t: %d\n", *x, *y, r, t);
 }
 
 //static void get_rt_from_xy(int *r, int *t, int x, int y){
@@ -84,19 +85,18 @@ static void calculate_index_table(){
     for(int *r = radii; r < radii + NUM_LEDS_PER_WING; r++){    // This will have to be different for staggered leds/wings.
         for(int t = 0; t < THETA_RESOLUTION; t++){
             get_xy_from_rt(&x, &y, *r, t);
-            indices[r - radii][t] = x % var_info.xres + y * (x / var_info.xres);
+            indices[r - radii][t] = x + y * var_info.xres;
         }
     }
 }
 
 static void get_pixel_color(int fb_index, int *r, int *g, int *b){
     if(fb_index < var_info.xres * var_info.yres){
-        //printf("x: %d, y: %d\n", x, y);
-        //fb_pixel *p = &fb[x % var_info.xres + y * (x / var_info.xres)];
         fb_pixel *p = &fb[fb_index];
         *r = p->r;
         *g = p->g;
         *b = p->b;
+        //printf("i: %d, r: %d, g: %d, b: %d\n", fb_index, *r, *g, *b);   
     }    
 }
 
@@ -219,7 +219,7 @@ void *pov_run(){
         int msec = 0, trigger = 10; /* 10ms */
         clock_t before = clock();
         int cnt = 0;
-        while(cnt++ < 30000){
+        while(true || cnt++ < 60000){
             err = update_fb();
             if(err){
                 goto pov_cleanup;

pov.h

+// Real life measurements in cm:
+#define TOTAL_FAN_DIAMETER 130
+#define TOTAL_WING_LED_LENGTH 44
+#define FAN_DEADZONE_RADIUS 21
+
+// Fan characteristics:
 #define NUM_LEDS_PER_WING 64
 #define NUM_WINGS 1 // 5
-#define LED_SPACING 4   // Number of fb-pixels between each led.
-#define FAN_BLIND_ZONE_R 30  // Number of led-pixels in fan blind zone.
+
+// Misc.:
 #define THETA_RESOLUTION 1 // This should be set to something sort of reasonable. // 300
 #define POV_BUFFER_TYPE const volatile char
-#define POV_SCREEN_WIDTH 800
-#define POV_SCREEN_HEIGHT 600
-#define POV_SCREEN_BPP 8
-#define FRAME_BUFFER_SIZE POV_SCREEN_WIDTH * POV_SCREEN_HEIGHT //320*480
-
-// Total diameter of display: 130cm
-// Deadzone radius: 21cm
-// 44cm / 64 leds = 0.6875cm/led
-// => FAN_BLIND_ZONE_R = 30.5454
-// 800 pixels / 130cm = 6.154 pixels/cm
-// => 4.23 pixels/led
-
-typedef struct _fb_pixel{
-    uint8_t b;
-    uint8_t r;
-    uint8_t g;
-    uint8_t a;
+
+// FB-settings:
+#define POV_SCREEN_WIDTH 720
+#define POV_SCREEN_HEIGHT 480
+#define POV_SCREEN_BPP 16
+#define FRAME_BUFFER_SIZE POV_SCREEN_WIDTH * POV_SCREEN_HEIGHT * (POV_SCREEN_BPP / 8)
+
+// Calculated values:
+
+    // Total diameter of display: 130cm
+    // Deadzone radius: 21cm
+    // 44cm / 64 leds = 0.6875cm/led
+    // => FAN_BLIND_ZONE_R = 30.5454
+    // 800 pixels / 130cm = 6.154 pixels/cm
+    // => 4.23 pixels/led
+
+// Tip: Mess with constants until radii[NUM_LEDS - 1] is as close as possible to POV_SCREEN_WIDTH / 2.
+
+
+#define LED_SPACING (int)                                       \
+(                                                               \
+    ((float)POV_SCREEN_WIDTH / (float)TOTAL_FAN_DIAMETER)       \
+    * ((float)TOTAL_WING_LED_LENGTH / (float)NUM_LEDS_PER_WING) \
+)   // Number of fb-pixels between each led. 5 for 800x600.
+
+#define FAN_BLIND_ZONE_R (int)                                  \
+(                                                               \
+    (float) FAN_DEADZONE_RADIUS                                 \
+    / ((float)TOTAL_WING_LED_LENGTH / (float)NUM_LEDS_PER_WING) \
+)   // 31  // Number of led-pixels in fan blind zone.
+
+typedef struct _fb_pixel{   // 16bpp => RGB565 (BGR?)
+    uint16_t b : 5;
+    uint16_t g : 6;
+    uint16_t r : 5;
 } fb_pixel;
 
+
 typedef struct _led_pixel{
     uint8_t p;
     uint8_t b;