From b6d1c1b2f7e543d0e370c3b3332d2e54e4c31b00 Mon Sep 17 00:00:00 2001
From: ABelliqueux <contact@arthus.net>
Date: Sun, 14 Nov 2021 12:02:35 +0100
Subject: [PATCH] Fix typos, colors, add redux notice

---
 hello_spu_readback/README.md            |  5 ++++
 hello_spu_readback/hello_spu_readback.c | 32 +++++++++++++++----------
 2 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/hello_spu_readback/README.md b/hello_spu_readback/README.md
index 0b09dfe..0ec3e48 100644
--- a/hello_spu_readback/README.md
+++ b/hello_spu_readback/README.md
@@ -6,6 +6,11 @@ In this instance, it's used to determine the coordinates of a few primitives to
 
 This technique is known to be used in certain games for lipsynching or audio visualization ( Crash team racing, Hercules, Vib Ribbon ...).
 
+## pcsx-redux : no animation 
+
+Pcsx-redux does not yet support these specific SPU buffers nor triggerring IRQ from them so as of 11-2021 this example doesn't work in this particular emulator.  
+If looking for an alternative, check [duckstation](https://www.duckstation.org/) out.  
+
 ## PsyQ's SpuReadDecodedData() doc errata
 
 The main function for transferring data from the SPU to the RAM is `SpuReadDecodedData()`, and is documented in **LibRef47.pdf, p1054**.  
diff --git a/hello_spu_readback/hello_spu_readback.c b/hello_spu_readback/hello_spu_readback.c
index e22c131..70513ab 100644
--- a/hello_spu_readback/hello_spu_readback.c
+++ b/hello_spu_readback/hello_spu_readback.c
@@ -71,9 +71,9 @@ POLY_F4	* current[BARNUM];
 // Red : volume peak in the last 3 seconds
 POLY_F4	* peak[BARNUM];
 // Colors for the VU-metre
-CVECTOR bg = {0,90,255};
-CVECTOR fg = {255,190,0};
-CVECTOR cursor = {255,40,0};
+CVECTOR bg = {20, 10, 0};
+CVECTOR fg = {10,200,20};
+CVECTOR cursor = {200,40,10};
 
 void init(void)
 {
@@ -133,10 +133,14 @@ void initPrimitives(void)
         SetPolyF4 ( bar[i] );
         setRGB0 ( bar[i], bg.r,bg.g,bg.b );
         setXY4 ( bar[i],
-            MINBAR, BARTOP + i * MARGIN, /* NW */
-            MAXBAR, BARTOP + i * MARGIN, /* NE */
-            MINBAR, BARBOTTOM + i * MARGIN, /* SW */
-            MAXBAR, BARBOTTOM + i * MARGIN); /* SE */
+            // Top-left
+            MINBAR, BARTOP + i * MARGIN,
+            // Top-right
+            MAXBAR, BARTOP + i * MARGIN,
+            // Bottom-left
+            MINBAR, BARBOTTOM + i * MARGIN,
+            // Bottom-right
+            MAXBAR, BARBOTTOM + i * MARGIN);
 
         // Current volume is light purple-ish
         SetPolyF4 (current[i]);
@@ -284,7 +288,7 @@ void findSampleMaxVolume(void)
 
 int main(void)
 {    
-    // Values used to switch CD track after 
+    // Values used to switch CD track
     u_int counter = 0;
     int8_t flip = 1;
     // These will hold the normalised values of leftMax/rightMax, leftPeak/rightPeak
@@ -349,11 +353,13 @@ int main(void)
     // Those array will hold the return values of the CD commands
     u_char param[4], result[8];
     // Set CD parameters ; Report Mode ON, CD-DA ON. See LibeOver47.pdf, p.188
-    param[0] = CdlModeRept|CdlModeDA;	
-    CdControlB (CdlSetmode, param, 0);	/* set mode */
-    VSync (3);				/* wait three vsync times */
+    param[0] = CdlModeRept|CdlModeDA;
+    // Set CD mode
+    CdControlB (CdlSetmode, param, 0);	
+    // Wait 3 vsync
+    VSync (3);
     // Play second track in toc array
-    CdControlB (CdlPlay, (u_char *)&loc[3], 0);	/* play */
+    CdControlB (CdlPlay, (u_char *)&loc[3], 0);
     // Graphics setup 
     initPrimitives();    
     while (1) 
@@ -368,6 +374,7 @@ int main(void)
         rPeak = (rightPeak * 256) / 0x8000 + MINBAR;
         
         // Update primitives XY coordinates
+        // Set coordinates for volume bar polygons
         setXY4 ( current[LEFTBAR],
             MINBAR,     BARTOP,
             lMax + TSIZE, BARTOP,
@@ -378,6 +385,7 @@ int main(void)
             rMax + TSIZE, BARTOP + MARGIN,
             MINBAR,     BARBOTTOM + MARGIN,
             rMax + TSIZE, BARBOTTOM + MARGIN);
+        // Set coordinates for peak cursor polygons
         setXY4 (peak[LEFTBAR],
             lPeak,         BARTOP,
             lPeak + TSIZE, BARTOP,