[SOLVED] Improved CPU cache usage at packages/fcl-
image/src/pixtools.pp
lazarus / 64-FPC development

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lagprogramming · 2023-04-14 09:24

packages/fcl-image/src/pixtools.pp has:
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i procedure
FillRectangleColor (Canv:TFPCustomCanvas; x1,y1, x2,y2:integer; const
color:TFPColor);var x,y : integer;begin  SortRect (x1,y1, x2,y2); 
with Canv do    begin    for x := x1 to x2 do      for y := y1 to y2
do        DrawPixel(x,y,color);    end;end;Code: Pascal
 [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i procedure
FillRectangleImage (Canv:TFPCustomCanvas; x1,y1, x2,y2:integer; const
Image:TFPCustomImage);var x,y : integer;begin  with image do    for x
:= x1 to x2 do      for y := y1 to y2 do        Canv.DrawPixel(x,y,
colors[x mod width, y mod height]);end;Code: Pascal
 [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i procedure
FillRectangleImageRel (Canv:TFPCustomCanvas; x1,y1, x2,y2:integer;
const Image:TFPCustomImage);var x,y : integer;begin  with image do   
for x := x1 to x2 do      for y := y1 to y2 do       
Canv.DrawPixel(x,y, colors[(x-x1) mod width, (y-y1) mod height]);end;
The following patch improves CPU cache usage by switching the x and y
loops.
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i diff --git
a/packages/fcl-image/src/pixtools.pp b/packages/fcl-
image/src/pixtools.ppindex b8baccb5bb..da0fbfe700 100644---
a/packages/fcl-image/src/pixtools.pp+++ b/packages/fcl-
image/src/pixtools.pp@@ -73,8 +73,8 @@ procedure FillRectangleColor
(Canv:TFPCustomCanvas; x1,y1, x2,y2:integer; const   SortRect (x1,y1,
x2,y2);   with Canv do     begin-    for x := x1 to x2 do-      for y
:= y1 to y2 do+    for y := y1 to y2 do+      for x := x1 to x2 do   
    DrawPixel(x,y,color);     end; end;@@ -555,8 +555,8 @@ procedure
FillRectangleImage (Canv:TFPCustomCanvas; x1,y1, x2,y2:integer;
const var x,y : integer; begin   with image do-    for x := x1 to x2
do-      for y := y1 to y2 do+    for y := y1 to y2 do+      for x :=
x1 to x2 do         Canv.DrawPixel(x,y, colors[x mod width, y mod
height]); end; @@ -564,8 +564,8 @@ procedure FillRectangleImageRel
(Canv:TFPCustomCanvas; x1,y1, x2,y2:integer; con var x,y :
integer; begin   with image do-    for x := x1 to x2 do-      for y :=
y1 to y2 do+    for y := y1 to y2 do+      for x := x1 to x2 do      
 Canv.DrawPixel(x,y, colors[(x-x1) mod width, (y-y1) mod
height]); end;

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AlexTP · 2023-04-14 10:21

Posted to bugtracker,
https://gitlab.com/freepascal.org/fpc/source/-/issues/40242