decompile the monster that is sub_807CEBC

2 files changed, 131 insertions, 417 deletions

diff --git a/asm/field_weather.s b/asm/field_weather.s
index 92d2ffab2..399bf65d1 100644
--- a/asm/field_weather.s
+++ b/asm/field_weather.s
@@ -5,400 +5,6 @@
 
 	.text
 
-	thumb_func_start sub_807CEBC
-sub_807CEBC: @ 807CEBC
-	push {r4-r7,lr}
-	mov r7, r10
-	mov r6, r9
-	mov r5, r8
-	push {r5-r7}
-	sub sp, 0x8
-	lsls r0, 24
-	lsrs r3, r0, 24
-	adds r4, r3, 0
-	lsls r1, 24
-	lsrs r1, 24
-	mov r9, r1
-	lsls r2, 24
-	asrs r0, r2, 24
-	cmp r0, 0
-	bgt _0807CEDE
-	b _0807D048
-_0807CEDE:
-	subs r0, 0x1
-	lsls r0, 24
-	lsrs r0, 24
-	str r0, [sp]
-	lsls r5, r3, 4
-	adds r0, r1, r3
-	lsls r0, 24
-	lsrs r0, 24
-	mov r9, r0
-	cmp r4, r9
-	bcc _0807CEF6
-	b _0807D1A2
-_0807CEF6:
-	ldr r1, [sp]
-	lsls r0, r1, 24
-	asrs r0, 19
-	str r0, [sp, 0x4]
-_0807CEFE:
-	ldr r0, _0807CF30 @ =gUnknown_030006DC
-	ldr r0, [r0]
-	adds r0, r4
-	ldrb r0, [r0]
-	cmp r0, 0
-	bne _0807CF3C
-	lsls r1, r5, 1
-	ldr r0, _0807CF34 @ =gPlttBufferUnfaded
-	adds r0, r1, r0
-	ldr r2, _0807CF38 @ =gPlttBufferFaded
-	adds r1, r2
-	movs r2, 0x8
-	bl CpuFastSet
-	adds r0, r5, 0
-	adds r0, 0x10
-	lsls r0, 16
-	lsrs r5, r0, 16
-	mov r2, r9
-	lsls r2, 16
-	mov r8, r2
-	adds r4, 0x1
-	mov r12, r4
-	b _0807D032
-	.align 2, 0
-_0807CF30: .4byte gUnknown_030006DC
-_0807CF34: .4byte gPlttBufferUnfaded
-_0807CF38: .4byte gPlttBufferFaded
-_0807CF3C:
-	cmp r0, 0x2
-	beq _0807CF50
-	adds r1, r4, 0
-	subs r1, 0x10
-	ldr r2, _0807CF54 @ =gUnknown_0202F7E8
-	ldr r3, _0807CF58 @ =0x000006d5
-	adds r0, r2, r3
-	ldrb r0, [r0]
-	cmp r1, r0
-	bne _0807CF60
-_0807CF50:
-	ldr r0, _0807CF5C @ =gUnknown_0202FC48
-	b _0807CF66
-	.align 2, 0
-_0807CF54: .4byte gUnknown_0202F7E8
-_0807CF58: .4byte 0x000006d5
-_0807CF5C: .4byte gUnknown_0202FC48
-_0807CF60:
-	movs r3, 0x80
-	lsls r3, 2
-	adds r0, r2, r3
-_0807CF66:
-	ldr r1, [sp, 0x4]
-	adds r6, r1, r0
-	cmp r4, 0x10
-	beq _0807CF72
-	cmp r4, 0x1B
-	bls _0807CFE2
-_0807CF72:
-	movs r7, 0
-	mov r2, r9
-	lsls r2, 16
-	mov r8, r2
-	adds r4, 0x1
-	mov r12, r4
-	ldr r3, _0807CF9C @ =gPlttBufferFaded
-	mov r10, r3
-_0807CF82:
-	adds r2, r5, 0
-	lsls r0, r5, 1
-	ldr r4, _0807CFA0 @ =gPlttBufferUnfaded
-	adds r1, r0, r4
-	ldrh r0, [r1]
-	ldr r3, _0807CFA4 @ =0x00002d9f
-	cmp r0, r3
-	bne _0807CFA8
-	adds r0, r5, 0x1
-	lsls r0, 16
-	lsrs r5, r0, 16
-	b _0807CFD6
-	.align 2, 0
-_0807CF9C: .4byte gPlttBufferFaded
-_0807CFA0: .4byte gPlttBufferUnfaded
-_0807CFA4: .4byte 0x00002d9f
-_0807CFA8:
-	ldr r1, [r1]
-	lsls r0, r1, 27
-	lsrs r0, 27
-	adds r0, r6, r0
-	ldrb r4, [r0]
-	lsls r0, r1, 22
-	lsrs r0, 27
-	adds r0, r6, r0
-	ldrb r3, [r0]
-	lsls r1, 17
-	lsrs r1, 27
-	adds r1, r6, r1
-	ldrb r1, [r1]
-	adds r0, r5, 0x1
-	lsls r0, 16
-	lsrs r5, r0, 16
-	lsls r2, 1
-	add r2, r10
-	lsls r0, r1, 10
-	lsls r1, r3, 5
-	orrs r0, r1
-	orrs r0, r4
-	strh r0, [r2]
-_0807CFD6:
-	adds r0, r7, 0x1
-	lsls r0, 16
-	lsrs r7, r0, 16
-	cmp r7, 0xF
-	bls _0807CF82
-	b _0807D032
-_0807CFE2:
-	movs r7, 0
-	mov r0, r9
-	lsls r0, 16
-	mov r8, r0
-	adds r4, 0x1
-	mov r12, r4
-	ldr r1, _0807D040 @ =gPlttBufferFaded
-	mov r10, r1
-_0807CFF2:
-	adds r2, r5, 0
-	lsls r0, r2, 1
-	ldr r3, _0807D044 @ =gPlttBufferUnfaded
-	adds r0, r3
-	ldr r1, [r0]
-	lsls r0, r1, 27
-	lsrs r0, 27
-	adds r0, r6, r0
-	ldrb r4, [r0]
-	lsls r0, r1, 22
-	lsrs r0, 27
-	adds r0, r6, r0
-	ldrb r3, [r0]
-	lsls r1, 17
-	lsrs r1, 27
-	adds r1, r6, r1
-	ldrb r1, [r1]
-	adds r0, r2, 0x1
-	lsls r0, 16
-	lsrs r5, r0, 16
-	lsls r2, 1
-	add r2, r10
-	lsls r0, r1, 10
-	lsls r1, r3, 5
-	orrs r0, r1
-	orrs r0, r4
-	strh r0, [r2]
-	adds r0, r7, 0x1
-	lsls r0, 16
-	lsrs r7, r0, 16
-	cmp r7, 0xF
-	bls _0807CFF2
-_0807D032:
-	mov r4, r12
-	lsls r0, r4, 16
-	lsrs r4, r0, 16
-	cmp r0, r8
-	bcs _0807D03E
-	b _0807CEFE
-_0807D03E:
-	b _0807D1A2
-	.align 2, 0
-_0807D040: .4byte gPlttBufferFaded
-_0807D044: .4byte gPlttBufferUnfaded
-_0807D048:
-	cmp r0, 0
-	blt _0807D04E
-	b _0807D190
-_0807D04E:
-	mvns r0, r0
-	lsls r0, 24
-	lsrs r0, 24
-	str r0, [sp]
-	lsls r5, r3, 4
-	adds r0, r1, r3
-	lsls r0, 24
-	lsrs r0, 24
-	mov r9, r0
-	adds r4, r3, 0
-	cmp r4, r9
-	bcc _0807D068
-	b _0807D1A2
-_0807D068:
-	ldr r0, _0807D098 @ =gUnknown_030006DC
-	ldr r0, [r0]
-	adds r0, r4
-	ldrb r0, [r0]
-	cmp r0, 0
-	bne _0807D0A4
-	lsls r1, r5, 1
-	ldr r0, _0807D09C @ =gPlttBufferUnfaded
-	adds r0, r1, r0
-	ldr r2, _0807D0A0 @ =gPlttBufferFaded
-	adds r1, r2
-	movs r2, 0x8
-	bl CpuFastSet
-	adds r0, r5, 0
-	adds r0, 0x10
-	lsls r0, 16
-	lsrs r5, r0, 16
-	mov r0, r9
-	lsls r0, 16
-	mov r8, r0
-	adds r4, 0x1
-	mov r12, r4
-	b _0807D174
-	.align 2, 0
-_0807D098: .4byte gUnknown_030006DC
-_0807D09C: .4byte gPlttBufferUnfaded
-_0807D0A0: .4byte gPlttBufferFaded
-_0807D0A4:
-	cmp r4, 0x10
-	beq _0807D0AC
-	cmp r4, 0x1B
-	bls _0807D11C
-_0807D0AC:
-	movs r7, 0
-	mov r1, r9
-	lsls r1, 16
-	mov r8, r1
-	adds r4, 0x1
-	mov r12, r4
-	ldr r2, _0807D10C @ =0x02000000
-	mov r10, r2
-	ldr r3, [sp]
-	lsls r0, r3, 24
-	asrs r6, r0, 11
-_0807D0C2:
-	lsls r1, r5, 1
-	ldr r4, _0807D110 @ =gPlttBufferUnfaded
-	adds r0, r1, r4
-	ldrh r0, [r0]
-	lsls r4, r0, 16
-	ldr r2, _0807D114 @ =0x00002d9f
-	cmp r0, r2
-	beq _0807D0FA
-	ldr r3, _0807D118 @ =gPlttBufferFaded
-	adds r3, r1, r3
-	lsrs r0, r4, 17
-	movs r1, 0xF
-	ands r0, r1
-	lsrs r1, r4, 18
-	movs r2, 0xF0
-	ands r1, r2
-	orrs r0, r1
-	lsrs r1, r4, 19
-	movs r4, 0xF0
-	lsls r4, 4
-	adds r2, r4, 0
-	ands r1, r2
-	orrs r0, r1
-	lsls r0, 1
-	adds r0, r6
-	add r0, r10
-	ldrh r0, [r0]
-	strh r0, [r3]
-_0807D0FA:
-	adds r0, r5, 0x1
-	lsls r0, 16
-	lsrs r5, r0, 16
-	adds r0, r7, 0x1
-	lsls r0, 16
-	lsrs r7, r0, 16
-	cmp r7, 0xF
-	bls _0807D0C2
-	b _0807D174
-	.align 2, 0
-_0807D10C: .4byte 0x02000000
-_0807D110: .4byte gPlttBufferUnfaded
-_0807D114: .4byte 0x00002d9f
-_0807D118: .4byte gPlttBufferFaded
-_0807D11C:
-	movs r7, 0
-	ldr r1, [sp]
-	lsls r0, r1, 24
-	mov r2, r9
-	lsls r2, 16
-	mov r8, r2
-	adds r4, 0x1
-	mov r12, r4
-	ldr r3, _0807D184 @ =0x02000000
-	mov r10, r3
-	asrs r6, r0, 11
-_0807D132:
-	lsls r0, r5, 1
-	ldr r1, _0807D188 @ =gPlttBufferFaded
-	adds r4, r0, r1
-	ldr r2, _0807D18C @ =gPlttBufferUnfaded
-	adds r0, r2
-	ldrh r3, [r0]
-	lsls r3, 16
-	lsrs r0, r3, 17
-	movs r1, 0xF
-	ands r0, r1
-	lsrs r1, r3, 18
-	movs r2, 0xF0
-	ands r1, r2
-	orrs r0, r1
-	lsrs r3, 19
-	movs r2, 0xF0
-	lsls r2, 4
-	adds r1, r2, 0
-	ands r3, r1
-	orrs r0, r3
-	lsls r0, 1
-	adds r0, r6
-	add r0, r10
-	ldrh r0, [r0]
-	strh r0, [r4]
-	adds r0, r5, 0x1
-	lsls r0, 16
-	lsrs r5, r0, 16
-	adds r0, r7, 0x1
-	lsls r0, 16
-	lsrs r7, r0, 16
-	cmp r7, 0xF
-	bls _0807D132
-_0807D174:
-	mov r3, r12
-	lsls r0, r3, 16
-	lsrs r4, r0, 16
-	cmp r0, r8
-	bcs _0807D180
-	b _0807D068
-_0807D180:
-	b _0807D1A2
-	.align 2, 0
-_0807D184: .4byte 0x02000000
-_0807D188: .4byte gPlttBufferFaded
-_0807D18C: .4byte gPlttBufferUnfaded
-_0807D190:
-	lsls r1, r4, 5
-	ldr r0, _0807D1B4 @ =gPlttBufferUnfaded
-	adds r0, r1, r0
-	ldr r2, _0807D1B8 @ =gPlttBufferFaded
-	adds r1, r2
-	mov r4, r9
-	lsls r2, r4, 3
-	bl CpuFastSet
-_0807D1A2:
-	add sp, 0x8
-	pop {r3-r5}
-	mov r8, r3
-	mov r9, r4
-	mov r10, r5
-	pop {r4-r7}
-	pop {r0}
-	bx r0
-	.align 2, 0
-_0807D1B4: .4byte gPlttBufferUnfaded
-_0807D1B8: .4byte gPlttBufferFaded
-	thumb_func_end sub_807CEBC
-
 	thumb_func_start sub_807D1BC
 sub_807D1BC: @ 807D1BC
 	push {r4-r7,lr}
diff --git a/src/field_weather.c b/src/field_weather.c
index 5ff2eddf9..366d57824 100644
--- a/src/field_weather.c
+++ b/src/field_weather.c
@@ -4,11 +4,15 @@
 #include "sprite.h"
 #include "task.h"
 
+#define MACRO1(a) ((((a) >> 1) & 0xF) | (((a) >> 2) & 0xF0) | (((a) >> 3) & 0xF00))
+
 struct Weather
 {
     u8 filler_000[0x200];
     u8 unknown_200[2][32];
-    u8 filler_240[0x480];
+    u8 filler_240[0x460-0x240];
+    u8 unk460[2][32];
+    u8 filler4A0[0x6C0-0x4A0];
     s8 unknown_6C0;
     s8 unknown_6C1;
     u8 unknown_6C2;
@@ -184,26 +188,18 @@ void sub_807CB10(void)
     for (v0 = 0; v0 <= 1; v0++)
     {
         if (v0 == 0)
-        {
             v1 = &gUnknown_0202F9E8;
-        }
         else
-        {
             v1 = &gUnknown_0202F9E8 + 19;
-        }
+
         for (v2 = 0; (u16)v2 <= 0x1f; v2++)
         {
             v4 = v2 << 8;
             if (v0 == 0)
-            {
                 v5 = (v2 << 8) / 16;
-            }
             else
-            {
                 v5 = 0;
-            }
-            v6 = 0;
-            for (; v6 <= 2; v6++)
+            for (v6 = 0; v6 <= 2; v6++)
             {
                 v4 = (v4 - v5);
                 v1[v6][v2] = v4 >> 8;
@@ -260,13 +256,9 @@ void sub_807CC24(void)
         {
             gWeather.unknown_6C3 = 0;
             if (gWeather.unknown_6C0 < gWeather.unknown_6C1)
-            {
                 gWeather.unknown_6C0++;
-            }
             else
-            {
                 gWeather.unknown_6C0--;
-            }
             sub_807CEBC(0, 0x20, gWeather.unknown_6C0);
         }
     }
@@ -275,9 +267,7 @@ void sub_807CC24(void)
 void sub_807CCAC(void)
 {
     if (++gWeather.unknown_6CB > 1)
-    {
         gWeather.unknown_6CA = 0;
-    }
     switch (gWeather.unknown_6D0)
     {
     case 3:
@@ -322,9 +312,7 @@ void sub_807CCAC(void)
 u8 sub_807CDC4(void)
 {
     if (gWeather.unknown_6C7 == 0x10)
-    {
         return 0;
-    }
     if (++gWeather.unknown_6C7 >= 0x10)
     {
         sub_807CEBC(0, 0x20, 3);
@@ -338,9 +326,7 @@ u8 sub_807CDC4(void)
 u8 sub_807CE24(void)
 {
     if (gWeather.unknown_6C7 == 0x10)
-    {
         return 0;
-    }
     if (++gWeather.unknown_6C7 >= 0x10)
     {
         sub_807CEBC(0, 0x20, -6);
@@ -354,9 +340,7 @@ u8 sub_807CE24(void)
 u8 sub_807CE7C(void)
 {
     if (gWeather.unknown_6C7 == 0x10)
-    {
         return 0;
-    }
     ++gWeather.unknown_6C7;
     sub_807D424(0x10 - gWeather.unknown_6C7, gWeather.unknown_6C4);
     return 1;
@@ -365,3 +349,127 @@ u8 sub_807CE7C(void)
 void nullsub_39(void)
 {
 }
+
+struct RGBColor
+{
+    u16 r:5;
+    u16 g:5;
+    u16 b:5;
+};
+
+extern u8 ewram[];
+
+struct Struct2000000
+{
+    u16 data[0][0x1000];  // unknown length
+};
+
+#define ewram0 (*(struct Struct2000000 *)ewram)
+
+void sub_807CEBC(u8 a, u8 b, s8 c)
+{
+    u16 r4;
+    u16 r5;
+    u8 *r6;
+    u16 r7;
+
+    if (c > 0)
+    {
+        c = c - 1;
+        r5 = a * 16;
+        b += a;
+        r4 = a;
+        while (r4 < b)
+        {
+            if (gUnknown_030006DC[r4] == 0)
+            {
+                CpuFastCopy(gPlttBufferUnfaded + r5, gPlttBufferFaded + r5, 16 * sizeof(u16));
+                r5 += 16;
+            }
+            else
+            {
+                u8 r, g, b;
+
+                if (gUnknown_030006DC[r4] == 2 || r4 - 16 == gUnknown_0202F7E8.unknown_6D5)
+                    r6 = gUnknown_0202F7E8.unk460[c];
+                else
+                    r6 = gUnknown_0202F7E8.unknown_200[c];
+                if (r4 == 16 || r4 > 0x1B)
+                {
+                    for (r7 = 0; r7 < 16; r7++)
+                    {
+                        if (gPlttBufferUnfaded[r5] == 0x2D9F)
+                        {
+                            r5++;
+                        }
+                        else
+                        {
+                            struct RGBColor r1 = *(struct RGBColor *)&gPlttBufferUnfaded[r5];
+                            r = r6[r1.r];
+                            g = r6[r1.g];
+                            b = r6[r1.b];
+
+                            gPlttBufferFaded[r5++] = (b << 10) | (g << 5) | r;
+                        }
+                    }
+                }
+                else
+                {
+                    for (r7 = 0; r7 < 16; r7++)
+                    {
+                        struct RGBColor r1 = *(struct RGBColor *)&gPlttBufferUnfaded[r5];
+                        r = r6[r1.r];
+                        g = r6[r1.g];
+                        b = r6[r1.b];
+
+                        gPlttBufferFaded[r5++] = (b << 10) | (g << 5) | r;
+                    }
+                }
+            }
+            r4++;
+        }
+    }
+    else
+    {
+        if (c < 0)
+        {
+            c = -c - 1;
+            r5 = a * 16;
+            b += a;
+            r4 = a;
+            while (r4 < b)
+            {
+                if (gUnknown_030006DC[r4] == 0)
+                {
+                    CpuFastCopy(gPlttBufferUnfaded + r5, gPlttBufferFaded + r5, 16 * sizeof(u16));
+                    r5 += 16;
+                }
+                else
+                {
+                    if (r4 == 16 || r4 > 0x1B)
+                    {
+                        for (r7 = 0; r7 < 16; r7++)
+                        {
+                            if (gPlttBufferUnfaded[r5] != 0x2D9F)
+                                gPlttBufferFaded[r5] = ewram0.data[c][MACRO1(gPlttBufferUnfaded[r5])];
+                            r5++;
+                        }
+                    }
+                    else
+                    {
+                        for (r7 = 0; r7 < 16; r7++)
+                        {
+                            gPlttBufferFaded[r5] = ewram0.data[c][MACRO1(gPlttBufferUnfaded[r5])];
+                            r5++;
+                        }
+                    }
+                }
+                r4++;
+            }
+        }
+        else
+        {
+            CpuFastCopy(gPlttBufferUnfaded + a * 16, gPlttBufferFaded + a * 16, b * 16 * sizeof(u16));
+        }
+    }
+}