From 988ec17ebfce513fc4589f7b12e0d6e3894ae542 Mon Sep 17 00:00:00 2001
From: TuxSH <1922548+TuxSH@users.noreply.github.com>
Date: Sat, 22 Jun 2024 01:22:22 +0200
Subject: [PATCH] Screenshots: when dealing with 800px mode, produce 800x480
 instead of 800x240 images for more faithful output

Each line is duplicated in this case (integer scaling 2)
---
 sysmodules/rosalina/include/draw.h |  2 +-
 sysmodules/rosalina/source/draw.c  | 18 +++++++++++-------
 sysmodules/rosalina/source/menus.c | 17 +++++++++++------
 3 files changed, 23 insertions(+), 14 deletions(-)

diff --git a/sysmodules/rosalina/include/draw.h b/sysmodules/rosalina/include/draw.h
index 1b77e47e2..af41027b1 100644
--- a/sysmodules/rosalina/include/draw.h
+++ b/sysmodules/rosalina/include/draw.h
@@ -108,4 +108,4 @@ u32 Draw_GetCurrentFramebufferAddress(bool top, bool left);
 void Draw_GetCurrentScreenInfo(u32 *width, bool *is3d, bool top);
 
 void Draw_CreateBitmapHeader(u8 *dst, u32 width, u32 heigth);
-void Draw_ConvertFrameBufferLines(u8 *buf, u32 width, u32 startingLine, u32 numLines, bool top, bool left);
+void Draw_ConvertFrameBufferLines(u8 *buf, u32 width, u32 startingLine, u32 numLines, u32 scaleFactorY, bool top, bool left);
diff --git a/sysmodules/rosalina/source/draw.c b/sysmodules/rosalina/source/draw.c
index 333f48a9b..ddfd58fd3 100644
--- a/sysmodules/rosalina/source/draw.c
+++ b/sysmodules/rosalina/source/draw.c
@@ -203,7 +203,7 @@ u32 Draw_SetupFramebuffer(void)
     GPU_FB_BOTTOM_ADDR_1 = GPU_FB_BOTTOM_ADDR_2 = FB_BOTTOM_VRAM_PA;
     GPU_FB_BOTTOM_FMT = format;
     GPU_FB_BOTTOM_STRIDE = 240 * 2;
-    
+
     gpuSavedFillColor = LCD_BOT_FILLCOLOR;
     LCD_BOT_FILLCOLOR = 0;
 
@@ -214,7 +214,7 @@ void Draw_RestoreFramebuffer(void)
 {
     memcpy(FB_BOTTOM_VRAM_ADDR, framebufferCache, FB_BOTTOM_SIZE);
     Draw_FlushFramebuffer();
-    
+
     LCD_BOT_FILLCOLOR = gpuSavedFillColor;
     GPU_FB_BOTTOM_ADDR_1 = gpuSavedFramebufferAddr1;
     GPU_FB_BOTTOM_ADDR_2 = gpuSavedFramebufferAddr2;
@@ -350,6 +350,7 @@ typedef struct FrameBufferConvertArgs {
     u32 width;
     u8 startingLine;
     u8 numLines;
+    u8 scaleFactorY;
     bool top;
     bool left;
 } FrameBufferConvertArgs;
@@ -367,16 +368,19 @@ static void Draw_ConvertFrameBufferLinesKernel(const FrameBufferConvertArgs *arg
 
     for (u32 y = args->startingLine; y < args->startingLine + args->numLines; y++)
     {
-        for(u32 x = 0; x < width; x++)
+        for (u8 i = 0; i < args->scaleFactorY; i++)
         {
-            __builtin_prefetch(addr + x * stride + y * formatSizes[fmt], 0, 3);
-            Draw_ConvertPixelToBGR8(args->buf + (x + width * y) * 3 , addr + x * stride + y * formatSizes[fmt], fmt);
+            for(u32 x = 0; x < width; x++)
+            {
+                __builtin_prefetch(addr + x * stride + y * formatSizes[fmt], 0, 3);
+                Draw_ConvertPixelToBGR8(args->buf + (x + width * (args->scaleFactorY * y + i)) * 3 , addr + x * stride + y * formatSizes[fmt], fmt);
+            }
         }
     }
 }
 
-void Draw_ConvertFrameBufferLines(u8 *buf, u32 width, u32 startingLine, u32 numLines, bool top, bool left)
+void Draw_ConvertFrameBufferLines(u8 *buf, u32 width, u32 startingLine, u32 numLines, u32 scaleFactorY, bool top, bool left)
 {
-    FrameBufferConvertArgs args = { buf, width, (u8)startingLine, (u8)numLines, top, left };
+    FrameBufferConvertArgs args = { buf, width, (u8)startingLine, (u8)numLines, (u8)scaleFactorY, top, left };
     svcCustomBackdoor(Draw_ConvertFrameBufferLinesKernel, &args);
 }
diff --git a/sysmodules/rosalina/source/menus.c b/sysmodules/rosalina/source/menus.c
index 4e23ae8f7..9b741707f 100644
--- a/sysmodules/rosalina/source/menus.c
+++ b/sysmodules/rosalina/source/menus.c
@@ -362,7 +362,12 @@ static Result RosalinaMenu_WriteScreenshot(IFile *file, u32 width, bool top, boo
     u64 total;
     Result res = 0;
     u32 lineSize = 3 * width;
-    u32 remaining = lineSize * 240;
+
+    // When dealing with 800px mode (800x240 with half-width pixels), duplicate each line
+    // to restore aspect ratio and obtain faithful 800x480 screenshots
+    u32 scaleFactorY = width > 400 ? 2 : 1;
+    u32 numLinesScaled = 240 * scaleFactorY;
+    u32 remaining = lineSize * numLinesScaled;
 
     TRY(Draw_AllocateFramebufferCacheForScreenshot(remaining));
 
@@ -370,7 +375,7 @@ static Result RosalinaMenu_WriteScreenshot(IFile *file, u32 width, bool top, boo
     u8 *framebufferCacheEnd = framebufferCache + Draw_GetFramebufferCacheSize();
 
     u8 *buf = framebufferCache;
-    Draw_CreateBitmapHeader(framebufferCache, width, 240);
+    Draw_CreateBitmapHeader(framebufferCache, width, numLinesScaled);
     buf += 54;
 
     u32 y = 0;
@@ -380,16 +385,16 @@ static Result RosalinaMenu_WriteScreenshot(IFile *file, u32 width, bool top, boo
         s64 t0 = svcGetSystemTick();
         u32 available = (u32)(framebufferCacheEnd - buf);
         u32 size = available < remaining ? available : remaining;
-        u32 nlines = size / lineSize;
-        Draw_ConvertFrameBufferLines(buf, width, y, nlines, top, left);
+        u32 nlines = size / (lineSize * scaleFactorY);
+        Draw_ConvertFrameBufferLines(buf, width, y, nlines, scaleFactorY, top, left);
 
         s64 t1 = svcGetSystemTick();
         timeSpentConvertingScreenshot += t1 - t0;
-        TRY(IFile_Write(file, &total, framebufferCache, (y == 0 ? 54 : 0) + lineSize * nlines, 0)); // don't forget to write the header
+        TRY(IFile_Write(file, &total, framebufferCache, (y == 0 ? 54 : 0) + lineSize * nlines * scaleFactorY, 0)); // don't forget to write the header
         timeSpentWritingScreenshot += svcGetSystemTick() - t1;
 
         y += nlines;
-        remaining -= lineSize * nlines;
+        remaining -= lineSize * nlines * scaleFactorY;
         buf = framebufferCache;
     }
     end: