add initial brightness config dialog, currently inaccessible

arm11/source/main.c

@@ -148,10 +148,11 @@ void PXI_RX_Handler(u32 __attribute__((unused)) irqn)
 		case PXI_BRIGHTNESS:
 		{
 			ret = LCD_GetBrightness();
-			if (args[0] && (args[0] < 0x100)) {
+			if ((args[0] > 0) && (args[0] < 0x100)) {
 				LCD_SetBrightness(args[0]);
 				auto_brightness = false;
 			} else {
+				prev_bright_lvl = -1;
 				auto_brightness = true;
 			}
 			break;

arm9/source/common/power.c

@@ -3,6 +3,18 @@
 #include "i2c.h"
 #include "pxi.h"
 
+u32 SetScreenBrightness(int level) {
+    u32 arg;
+
+    if (level != BRIGHTNESS_AUTOMATIC) {
+        arg = clamp(level, BRIGHTNESS_MIN, BRIGHTNESS_MAX);
+    } else {
+        arg = 0;
+    }
+
+    return PXI_DoCMD(PXI_BRIGHTNESS, &arg, 1);
+}
+
 u32 GetBatteryPercent() {
     u8 battery = 0;
     I2C_readRegBuf(I2C_DEV_MCU, 0x0B, &battery, 1);

arm9/source/common/power.h

@@ -2,6 +2,11 @@
 
 #include "common.h"
 
+#define BRIGHTNESS_AUTOMATIC (-1)
+#define BRIGHTNESS_MIN (10)
+#define BRIGHTNESS_MAX (210)
+
+u32 SetScreenBrightness(int level);
 u32 GetBatteryPercent();
 bool IsCharging();
 void Reboot();

arm9/source/common/ui.c

@@ -14,6 +14,7 @@
 #include "timer.h"
 #include "power.h"
 #include "hid.h"
+#include "fixp.h"
 
 #define STRBUF_SIZE 512 // maximum size of the string buffer
 #define FONT_MAX_WIDTH 8
@@ -1060,3 +1061,107 @@ bool ShowProgress(u64 current, u64 total, const char* opstr)
 
     return !CheckButton(BUTTON_B);
 }
+
+int ShowBrightnessConfig(int set_brightness)
+{
+    u32 btn_input, bar_count;
+    int bar_x_pos, bar_y_pos, bar_width, bar_height;
+
+    const char *brightness_str =
+        "[<] Decrease brightness\n"
+        "[>] Increase brightness\n"
+        "[X] Use the volume slider as control\n"
+        "\n"
+        "[A] Set screen brightness\n"
+        "[B] Exit";
+    static const u16 brightness_slider_colmasks[] = {
+        COLOR_RED, COLOR_GREEN, COLOR_BLUE, COLOR_WHITE
+    };
+
+    ClearScreen(MAIN_SCREEN, COLOR_STD_BG);
+
+    bar_count = countof(brightness_slider_colmasks);
+    bar_width = (SCREEN_WIDTH_MAIN / 8) * 6;
+    bar_x_pos = SCREEN_WIDTH_MAIN / 8;
+
+    bar_height = 10;
+    bar_y_pos = SCREEN_HEIGHT / 4;
+
+    // default to average brightness if invalid / automatic
+    if (set_brightness < BRIGHTNESS_MIN || set_brightness > BRIGHTNESS_MAX)
+        set_brightness = (BRIGHTNESS_MAX + BRIGHTNESS_MIN) / 2;
+
+    // draw initial UI stuff
+    DrawStringF(MAIN_SCREEN,
+        (SCREEN_WIDTH_MAIN - GetDrawStringWidth(brightness_str)) / 2,
+        (SCREEN_HEIGHT / 4) * 3, COLOR_STD_FONT, COLOR_STD_BG, brightness_str);
+
+    // draw all color gradient bars
+    for (int x = 0; x < bar_width; x++) {
+        u32 intensity;
+        u16 intensity_mask;
+
+        intensity = FIXP_TO_INT(fixp_changespace(
+            INT_TO_FIXP(x),
+            INT_TO_FIXP(0), INT_TO_FIXP(bar_width),
+            INT_TO_FIXP(0), INT_TO_FIXP(256)
+        ));
+
+        intensity_mask = RGB(intensity, intensity, intensity);
+
+        for (u32 b = 0; b < bar_count; b++) {
+            u16 *screen_base = &MAIN_SCREEN[PIXEL_OFFSET(bar_x_pos + x, (b * bar_height) + bar_y_pos)];
+            for (int y = 0; y < bar_height; y++)
+                *(screen_base++) = brightness_slider_colmasks[b] & intensity_mask;
+        }
+    }
+
+    while(1) {
+        int old_br, slider_x_pos, slider_y_pos;
+
+        old_br = set_brightness;
+        slider_y_pos = bar_y_pos + (bar_height * 3) + font_height;
+
+        if (set_brightness != BRIGHTNESS_AUTOMATIC) {
+            slider_x_pos = bar_x_pos + font_width + FIXP_TO_INT(fixp_changespace(
+                INT_TO_FIXP(set_brightness),
+                INT_TO_FIXP(BRIGHTNESS_MIN), INT_TO_FIXP(BRIGHTNESS_MAX),
+                INT_TO_FIXP(0), INT_TO_FIXP(bar_width)
+            ));
+
+            // redraw the slider position character (if necessary)
+            DrawCharacter(MAIN_SCREEN, '^', slider_x_pos,
+                slider_y_pos, COLOR_STD_FONT, COLOR_STD_BG);
+        }
+
+        btn_input = InputWait(0);
+
+        // draw a small rectangle to clear the character
+        if (set_brightness != BRIGHTNESS_AUTOMATIC) {
+            DrawRectangle(MAIN_SCREEN, slider_x_pos,
+                slider_y_pos, font_width, font_height, COLOR_STD_BG);
+        }
+
+        if (btn_input & BUTTON_LEFT) {
+            set_brightness -= 10;
+        } else if (btn_input & BUTTON_RIGHT) {
+            set_brightness += 10;
+        } else if (btn_input & BUTTON_X) {
+            set_brightness = BRIGHTNESS_AUTOMATIC;
+        } else if (btn_input & BUTTON_B) {
+            set_brightness = 0;
+            break;
+        } else if (btn_input & BUTTON_A) {
+            break;
+        }
+
+        if (set_brightness != BRIGHTNESS_AUTOMATIC)
+            set_brightness = clamp(set_brightness, BRIGHTNESS_MIN, BRIGHTNESS_MAX);
+
+        if (set_brightness != old_br)
+            SetScreenBrightness(set_brightness);
+    }
+
+    ClearScreen(MAIN_SCREEN, COLOR_STD_BG);
+    return set_brightness;
+}

arm9/source/common/ui.h

@@ -85,3 +85,5 @@ u64 ShowNumberPrompt(u64 start_val, const char *format, ...);
 bool ShowDataPrompt(u8* data, u32* size, const char *format, ...);
 bool ShowRtcSetterPrompt(void* time, const char *format, ...);
 bool ShowProgress(u64 current, u64 total, const char* opstr);
+
+int ShowBrightnessConfig(int set_brightness);

common/fixp.h

@@ -53,3 +53,8 @@ static inline fixp_t fixp_round(fixp_t n)
 {
 	return (n + FIXP_HALF_UNIT) & FIXP_UNIT_MASK;
 }
+
+static inline fixp_t fixp_changespace(fixp_t n, fixp_t lower_s, fixp_t upper_s, fixp_t lower_d, fixp_t upper_d)
+{
+	return fixp_product(n - lower_s, fixp_quotient(upper_d, upper_s)) + lower_d;
+}