From 1cecf9d1d7cf275e43f585f5e1547bfb03e270ec Mon Sep 17 00:00:00 2001
From: vit9696 <vit9696@users.noreply.github.com>
Date: Sun, 2 Feb 2020 05:28:56 +0300
Subject: [PATCH] OcConsoleLib: Improve ASCII renderer performance and fix
 glitches

---
 Library/OcConsoleLib/AsciiTextOutput.c | 23 ++++++++++++++++++-----
 1 file changed, 18 insertions(+), 5 deletions(-)

diff --git a/Library/OcConsoleLib/AsciiTextOutput.c b/Library/OcConsoleLib/AsciiTextOutput.c
index 8ab7994f..7ca30e0c 100644
--- a/Library/OcConsoleLib/AsciiTextOutput.c
+++ b/Library/OcConsoleLib/AsciiTextOutput.c
@@ -382,18 +382,31 @@ AsciiTextOutputString (
 
     if ((UINTN) This->Mode->CursorRow >= mConsoleHeight) {
       //
-      // TODO: Some GOP implementations (e.g. NVIDIA) cannot perform such operations.
+      // TODO: Many GOP implementations (e.g. NVIDIA) fail to perform overlapping operations.
       //
       mGraphicsOutput->Blt (
         mGraphicsOutput,
         NULL,
         EfiBltVideoToVideo,
-        TGT_CHAR_WIDTH,
+        0,
         TGT_CHAR_HEIGHT * 2,
-        TGT_CHAR_WIDTH,
+        0,
+        TGT_CHAR_HEIGHT,
+        mGraphicsOutput->Mode->Info->HorizontalResolution,
+        TGT_CHAR_HEIGHT * (mConsoleHeight - 1),
+        0
+        );
+
+      mGraphicsOutput->Blt (
+        mGraphicsOutput,
+        &mBackgroundColor.Pixel,
+        EfiBltVideoFill,
+        0,
+        0,
+        0,
+        TGT_CHAR_HEIGHT * mConsoleHeight,
+        mGraphicsOutput->Mode->Info->HorizontalResolution,
         TGT_CHAR_HEIGHT,
-        MIN (mConsoleMaxPosX * TGT_CHAR_WIDTH, mGraphicsOutput->Mode->Info->HorizontalResolution - TGT_CHAR_WIDTH),
-        MIN ((mConsoleMaxPosY + 1) * TGT_CHAR_HEIGHT, mGraphicsOutput->Mode->Info->VerticalResolution - TGT_CHAR_HEIGHT),
         0
         );