Match NRandInRange

TheOnlyZac · Jul 4, 2024 · 6b6466a · 6b6466a
1 parent f6069e3
commit 6b6466a
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Showing 4 changed files with 57 additions and 3 deletions.
diff --git a/config/sly1.yaml b/config/sly1.yaml
@@ -315,7 +315,7 @@ segments:
     #--------------------------------------------------------
     - [0xF69C4, asm] # TBD #MARK: libs
 
-    - [0xF76F8, c, sce/rand]
+    - [0xF76F8, asm, sce/rand]
 
     - [0xF7738, asm]
 

diff --git a/config/symbol_addrs.txt b/config/symbol_addrs.txt
@@ -287,7 +287,7 @@ RadSmooth = 0x1EA728; // type:func
 RadSmoothA = 0x1EA798; // type:func
 PosSmooth = 0x1EA818; // type:func
 SmoothMatrix = 0x1EA918; // type:func
-NRandInRange = 0x1EAA70; // type:func
+NRandInRange__Fii = 0x1EAA70; // type:func
 GRandInRange = 0x1EAAE0; // type:func
 GRandGaussian = 0x1EAB48; // type:func
 FFloatsNear = 0x1EAC68; // type:func
@@ -336,6 +336,9 @@ __main__Fv = 0x1fae18; // type:func
 srand = 0x1F66F8; // type:func
 rand = 0x1F6708; // type:func
 
+g_rng = 0x276680; // size:0x5c
+g_prng = 0x27696c; // size:0x4
+
 
 // gcc/dp-bit.c
 dpcmp = 0x1FD308; // type:func

diff --git a/include/sce/rand.h b/include/sce/rand.h
@@ -0,0 +1,34 @@
+#include "common.h"
+
+struct RNG {
+    undefined4 field0_0x0;
+    undefined4 field1_0x4;
+    undefined4 field2_0x8;
+    undefined4 field3_0xc;
+    undefined4 field4_0x10;
+    undefined4 field5_0x14;
+    undefined4 field6_0x18;
+    undefined4 field7_0x1c;
+    undefined4 field8_0x20;
+    undefined4 field9_0x24;
+    undefined4 field10_0x28;
+    undefined4 field11_0x2c;
+    undefined4 field12_0x30;
+    undefined4 field13_0x34;
+    undefined4 field14_0x38;
+    undefined4 field15_0x3c;
+    undefined4 field16_0x40;
+    undefined4 field17_0x44;
+    undefined4 field18_0x48;
+    undefined4 field19_0x4c;
+    undefined4 field20_0x50;
+    undefined4 field21_0x54;
+    uint next;
+};
+
+extern "C" void srand(uint seed);
+
+extern "C" uint rand();
+
+extern struct RNG g_rng;
+extern struct RNG *g_prng;
diff --git a/src/P2/util.c b/src/P2/util.c
@@ -1,4 +1,5 @@
 #include <util.h>
+#include <sce/rand.h>
 
 static const float PI = 3.14159265359f;
 
@@ -26,7 +27,23 @@ INCLUDE_ASM(const s32, "P2/util", PosSmooth);
 
 INCLUDE_ASM(const s32, "P2/util", SmoothMatrix);
 
-INCLUDE_ASM(const s32, "P2/util", NRandInRange);
+const int PRIME_MOD = 0x95675;
+
+// Generates a random integer in the range [nLow, nHi]
+int NRandInRange(int nLow, int nHi) {
+    if (nLow == nHi)
+    {
+        return nLow;
+    }
+
+    int randVal = rand();
+    randVal = randVal % PRIME_MOD;
+
+    int range = (nHi - nLow) + 1;
+
+    // Return a value within the range [nLow, nHi]
+    return nLow + (randVal % range);
+}
 
 INCLUDE_ASM(const s32, "P2/util", GRandInRange);