From 014bf55cd462fed2c6bcfcf7a076e54cfe7d6bb4 Mon Sep 17 00:00:00 2001
From: Lignum <me@lignum.pw>
Date: Sun, 31 May 2020 17:23:49 +0100
Subject: [PATCH] Cherry pick several improvements from #455

 - Use texture over texture2D - the latter was deprecated in GLSL 1.30.
 - Cache the tbo buffer - this saves an allocation when monitors update.

Closes #455. While the rest of the PR has some nice changes, it
performs signlificantly worse on my system.
---
 .../client/render/TileEntityMonitorRenderer.java       | 10 +++++++++-
 .../assets/computercraft/shaders/monitor.frag          |  2 +-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/main/java/dan200/computercraft/client/render/TileEntityMonitorRenderer.java b/src/main/java/dan200/computercraft/client/render/TileEntityMonitorRenderer.java
index 405a36a29..7dd003152 100644
--- a/src/main/java/dan200/computercraft/client/render/TileEntityMonitorRenderer.java
+++ b/src/main/java/dan200/computercraft/client/render/TileEntityMonitorRenderer.java
@@ -35,6 +35,7 @@ import static dan200.computercraft.shared.peripheral.monitor.TileMonitor.RENDER_
 public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMonitor>
 {
     private static final float MARGIN = (float) (TileMonitor.RENDER_MARGIN * 1.1);
+    private static ByteBuffer tboContents;
 
     @Override
     public void render( @Nonnull TileMonitor tileEntity, double posX, double posY, double posZ, float f, int i, float f2 )
@@ -162,7 +163,14 @@ public class TileEntityMonitorRenderer extends TileEntitySpecialRenderer<TileMon
 
                 if( redraw )
                 {
-                    ByteBuffer monitorBuffer = GLAllocation.createDirectByteBuffer( width * height * 3 );
+                    int size = width * height * 3;
+                    if( tboContents == null || tboContents.capacity() < size )
+                    {
+                        tboContents = GLAllocation.createDirectByteBuffer( size );
+                    }
+
+                    ByteBuffer monitorBuffer = tboContents;
+                    monitorBuffer.position( 0 );
                     for( int y = 0; y < height; y++ )
                     {
                         TextBuffer text = terminal.getLine( y ), textColour = terminal.getTextColourLine( y ), background = terminal.getBackgroundColourLine( y );
diff --git a/src/main/resources/assets/computercraft/shaders/monitor.frag b/src/main/resources/assets/computercraft/shaders/monitor.frag
index 3e1796932..b0b7b49ed 100644
--- a/src/main/resources/assets/computercraft/shaders/monitor.frag
+++ b/src/main/resources/assets/computercraft/shaders/monitor.frag
@@ -35,6 +35,6 @@ void main() {
     int bg = int(texelFetch(u_tbo, index + 2).r * 255.0);
 
     vec2 pos = (term_pos - corner) * vec2(FONT_WIDTH, FONT_HEIGHT);
-    vec4 img = texture2D(u_font, (texture_corner(character) + pos) / 256.0);
+    vec4 img = texture(u_font, (texture_corner(character) + pos) / 256.0);
     colour = vec4(mix(u_palette[bg], img.rgb * u_palette[fg], img.a * mult), 1.0);
 }