Decompile SetMatrixScale()

4 files changed, 43 insertions, 118 deletions

diff --git a/asm/intro.s b/asm/intro.s
index 5d3ff95..edc0a34 100755
--- a/asm/intro.s
+++ b/asm/intro.s
@@ -1349,7 +1349,7 @@ sub_9D70: @ 0x08009D70
 	movs r2, #0
 	ldrsh r1, [r4, r2]
 	movs r2, #0
-	bl sub_7C0
+	bl SetMatrixScale
 	ldrh r0, [r6]
 	mov r3, r8
 	strh r0, [r3, #2]
@@ -5643,7 +5643,7 @@ sub_C0D8: @ 0x0800C0D8
 	movs r2, #0
 	ldrsh r1, [r4, r2]
 	movs r2, #0
-	bl sub_7C0
+	bl SetMatrixScale
 	ldr r1, _0800C1FC @ =0x0201A450
 	ldrh r0, [r1]
 	mov r3, r8
@@ -7169,7 +7169,7 @@ sub_CD18: @ 0x0800CD18
 	movs r3, #0
 	ldrsh r1, [r1, r3]
 	movs r2, #0
-	bl sub_7C0
+	bl SetMatrixScale
 	ldrh r0, [r7]
 	strh r0, [r6, #2]
 	ldrh r0, [r7, #2]
diff --git a/asm/rom_11B9C.s b/asm/rom_11B9C.s
index 4e0cc2b..7252b58 100755
--- a/asm/rom_11B9C.s
+++ b/asm/rom_11B9C.s
@@ -1288,7 +1288,7 @@ _08012646:
 	ldrsh r1, [r7, r3]
 	adds r0, r1, #0
 	movs r2, #0
-	bl sub_7C0
+	bl SetMatrixScale
 	ldr r0, _080126C8 @ =0x020314E0
 	ldr r3, [r0]
 	adds r0, r3, #0
@@ -1459,7 +1459,7 @@ _080127A2:
 	ldrsh r1, [r7, r2]
 	adds r0, r1, #0
 	movs r2, #0
-	bl sub_7C0
+	bl SetMatrixScale
 	ldr r0, _08012828 @ =0x020314E0
 	ldr r3, [r0]
 	adds r0, r3, #0
@@ -31965,7 +31965,7 @@ _08021CB0:
 	movs r2, #0
 	ldrsh r1, [r1, r2]
 	movs r2, #1
-	bl sub_7C0
+	bl SetMatrixScale
 	movs r0, #0
 	ldr r6, _08021D6C @ =gOamBuffer
 	ldr r1, _08021D70 @ =0xFFFFFE00
@@ -47739,7 +47739,7 @@ _08029C84:
 	asrs r1, r1, #0x10
 	adds r0, r1, #0
 	movs r2, #2
-	bl sub_7C0
+	bl SetMatrixScale
 	movs r1, #0x80
 	mov r0, sp
 	ldrh r0, [r0, #2]
@@ -47753,7 +47753,7 @@ _08029CA0:
 	asrs r1, r1, #0x10
 	adds r0, r1, #0
 	movs r2, #3
-	bl sub_7C0
+	bl SetMatrixScale
 	ldr r0, [r4]
 	adds r0, r0, r6
 	ldrh r0, [r0]
@@ -47779,7 +47779,7 @@ _08029CD6:
 	asrs r1, r1, #0x10
 	adds r0, r1, #0
 	movs r2, #4
-	bl sub_7C0
+	bl SetMatrixScale
 	ldr r0, [r4]
 	adds r0, r0, r6
 	ldrh r0, [r0]
@@ -47806,7 +47806,7 @@ _08029D0E:
 	asrs r1, r1, #0x10
 	adds r0, r1, #0
 	movs r2, #5
-	bl sub_7C0
+	bl SetMatrixScale
 	ldr r0, _08029D38 @ =0x020314E0
 	ldr r1, [r0]
 	adds r2, r1, r6
@@ -53544,7 +53544,7 @@ _0802CBD6:
 	asrs r1, r1, #0x10
 	adds r0, r1, #0
 	movs r2, #6
-	bl sub_7C0
+	bl SetMatrixScale
 	ldr r0, _0802CCB0 @ =0x020314E0
 	ldr r1, [r0]
 	ldr r0, _0802CCB4 @ =0x00000286
@@ -68248,7 +68248,7 @@ _08034238:
 	adds r5, r4, #2
 	lsls r2, r5, #0x10
 	asrs r2, r2, #0x10
-	bl sub_7C0
+	bl SetMatrixScale
 	ldrh r0, [r6, #2]
 	subs r0, #0x10
 	strh r0, [r6, #2]
@@ -81029,22 +81029,22 @@ _0803AAE8:
 	adds r0, r5, #0
 	adds r1, r5, #0
 	movs r2, #1
-	bl sub_7C0
+	bl SetMatrixScale
 	rsbs r4, r5, #0
 	lsls r4, r4, #0x10
 	asrs r4, r4, #0x10
 	adds r0, r4, #0
 	adds r1, r5, #0
 	movs r2, #2
-	bl sub_7C0
+	bl SetMatrixScale
 	adds r0, r5, #0
 	adds r1, r4, #0
 	movs r2, #3
-	bl sub_7C0
+	bl SetMatrixScale
 	adds r0, r4, #0
 	adds r1, r4, #0
 	movs r2, #4
-	bl sub_7C0
+	bl SetMatrixScale
 	ldr r1, _0803AB48 @ =0x020314E0
 	ldr r0, [r1]
 	adds r1, r0, r7
@@ -87815,22 +87815,22 @@ _0803E26C:
 	adds r0, r5, #0
 	adds r1, r5, #0
 	movs r2, #1
-	bl sub_7C0
+	bl SetMatrixScale
 	rsbs r4, r5, #0
 	lsls r4, r4, #0x10
 	asrs r4, r4, #0x10
 	adds r0, r4, #0
 	adds r1, r5, #0
 	movs r2, #2
-	bl sub_7C0
+	bl SetMatrixScale
 	adds r0, r5, #0
 	adds r1, r4, #0
 	movs r2, #3
-	bl sub_7C0
+	bl SetMatrixScale
 	adds r0, r4, #0
 	adds r1, r4, #0
 	movs r2, #4
-	bl sub_7C0
+	bl SetMatrixScale
 	ldr r1, _0803E2BC @ =0x020314E0
 	ldr r0, [r1]
 	adds r1, r0, r6
@@ -106726,13 +106726,13 @@ _08047DBA:
 	lsls r1, r2, #0x10
 	asrs r1, r1, #0x10
 	movs r2, #3
-	bl sub_7C0
+	bl SetMatrixScale
 	ldr r3, [sp]
 	lsls r1, r3, #0x10
 	asrs r1, r1, #0x10
 	adds r0, r1, #0
 	movs r2, #4
-	bl sub_7C0
+	bl SetMatrixScale
 	ldr r4, _08047E74 @ =gMain
 	ldrh r1, [r4, #0x12]
 	cmp r1, #0xcb
@@ -110626,7 +110626,7 @@ _08049D92:
 	ldr r5, [sp, #0x10]
 	asrs r1, r5, #0x10
 	movs r2, #5
-	bl sub_7C0
+	bl SetMatrixScale
 	ldr r6, _08049EA4 @ =0x0200B470
 	movs r0, #0x64
 	mov r2, sl
diff --git a/asm/rom_24C.s b/asm/rom_24C.s
index 4e4687a..258919a 100755
--- a/asm/rom_24C.s
+++ b/asm/rom_24C.s
@@ -4,79 +4,6 @@
 
 	.text
 
-	thumb_func_start sub_7C0
-sub_7C0: @ 0x080007C0
-	push {r4, r5, r6, lr}
-	mov r6, r8
-	push {r6}
-	sub sp, #8
-	adds r3, r0, #0
-	adds r4, r1, #0
-	adds r5, r2, #0
-	lsls r4, r4, #0x10
-	lsrs r4, r4, #0x10
-	lsls r5, r5, #0x10
-	lsrs r5, r5, #0x10
-	lsls r3, r3, #0x10
-	asrs r3, r3, #0x10
-	movs r0, #0x80
-	lsls r0, r0, #9
-	mov r8, r0
-	adds r1, r3, #0
-	bl __divsi3
-	adds r6, r0, #0
-	lsls r6, r6, #0x10
-	lsrs r6, r6, #0x10
-	lsls r4, r4, #0x10
-	asrs r4, r4, #0x10
-	mov r0, r8
-	adds r1, r4, #0
-	bl __divsi3
-	mov r1, sp
-	strh r6, [r1]
-	mov r4, sp
-	adds r4, #2
-	movs r1, #0
-	strh r1, [r4]
-	add r6, sp, #4
-	strh r1, [r6]
-	lsls r0, r0, #0x10
-	lsrs r0, r0, #0x10
-	mov r1, sp
-	adds r1, #6
-	strh r0, [r1]
-	ldr r3, _0800084C @ =gOamBuffer
-	lsls r5, r5, #0x10
-	asrs r5, r5, #0x10
-	lsls r1, r5, #5
-	adds r1, r1, r3
-	mov r2, sp
-	ldrh r2, [r2]
-	strh r2, [r1, #6]
-	lsls r5, r5, #2
-	adds r1, r5, #1
-	lsls r1, r1, #3
-	adds r1, r1, r3
-	ldrh r2, [r4]
-	strh r2, [r1, #6]
-	adds r1, r5, #2
-	lsls r1, r1, #3
-	adds r1, r1, r3
-	ldrh r2, [r6]
-	strh r2, [r1, #6]
-	adds r5, #3
-	lsls r5, r5, #3
-	adds r5, r5, r3
-	strh r0, [r5, #6]
-	add sp, #8
-	pop {r3}
-	mov r8, r3
-	pop {r4, r5, r6}
-	pop {r0}
-	bx r0
-	.align 2, 0
-_0800084C: .4byte gOamBuffer
-
 	thumb_func_start sub_850
 sub_850: @ 0x08000850
 	ldr r0, _08000888 @ =0x04000208
diff --git a/src/main.c b/src/main.c
index e3571a1..e311b6f 100755
--- a/src/main.c
+++ b/src/main.c
@@ -277,25 +277,23 @@ static int sub_780(int arg0, int arg1)
         return 1 / var0;
 }
 
-// struct OamMatrix
-// {
-//     s16 a;
-//     s16 b;
-//     s16 c;
-//     s16 d;
-// };
-//
-// void sub_7C0(s16 arg0, s16 arg1, s16 matrixNum)
-// {
-//     u16 a = 0x10000 / arg0;
-//     u16 d = 0x10000 / arg1;
-//     volatile s16 a2 = a;
-//     volatile s16 b2 = 0;
-//     volatile s16 c2 = 0;
-//     volatile s16 d2 = d;
-
-//     gOamBuffer[matrixNum * 4 ].affineParam = a2;
-//     gOamBuffer[matrixNum * 4 + 1].affineParam = b2;
-//     gOamBuffer[matrixNum * 4 + 2].affineParam = c2;
-//     gOamBuffer[matrixNum * 4 + 3].affineParam = d;
-// }
+void SetMatrixScale(s16 xScale, s16 yScale, s16 matrixNum)
+{
+    vu16 a2, b2, c2, d2;
+    u16 a = 0x10000 / xScale;
+    u32 d = 0x10000 / yScale;
+    a2 = a;
+    b2 = 0;
+    c2 = 0;
+    // There is a delayed u16 shift here that is tricky to produce.
+#ifndef NONMATCHING
+    asm_unified("lsls r0, r0, #0x10\n\
+                 lsrs r0, r0, #0x10");
+#endif
+    d2 = d;
+
+    gOamBuffer[matrixNum * 4 ].affineParam = a2;
+    gOamBuffer[matrixNum * 4 + 1].affineParam = b2;
+    gOamBuffer[matrixNum * 4 + 2].affineParam = c2;
+    gOamBuffer[matrixNum * 4 + 3].affineParam = d;
+}