# HG changeset patch
# User frosch <frosch@openttd.org>
# Date 2018-11-15 22:12:37
# Node ID ea3c06180c6b369fd31c82d1b3b820c5cbea0dea
# Parent  945e32d3978c8ebe8690edafbdafbd953496d2d1

Revert: Sprite sorting optimisation sorted incorrectly.

This reverts commit 25ab9c1997f770f4a8a66bb3ad4b82ba87e3a977.

diff --git a/src/viewport.cpp b/src/viewport.cpp
--- a/src/viewport.cpp
+++ b/src/viewport.cpp
@@ -88,7 +88,6 @@
 #include "command_func.h"
 #include "network/network_func.h"
 #include "framerate_type.h"
-#include "core/sort_func.hpp"
 
 #include <map>
 
@@ -1380,22 +1379,11 @@ static bool ViewportSortParentSpritesChe
 	return true;
 }
 
-static int CDECL CompareParentSprites(ParentSpriteToDraw * const *psd, ParentSpriteToDraw * const *psd2)
-{
-	const ParentSpriteToDraw *ps = *psd;
-	const ParentSpriteToDraw *ps2 = *psd2;
-	return ps->xmin - ps2->xmin;
-}
-
 /** Sort parent sprites pointer array */
 static void ViewportSortParentSprites(ParentSpriteToSortVector *psdv)
 {
 	ParentSpriteToDraw **psdvend = psdv->End();
 	ParentSpriteToDraw **psd = psdv->Begin();
-
-	/* pre-sort by xmin in ascending order */
-	QSortT(psd, psdvend - psd, CompareParentSprites);
-
 	while (psd != psdvend) {
 		ParentSpriteToDraw *ps = *psd;
 
@@ -1432,11 +1420,9 @@ static void ViewportSortParentSprites(Pa
 				 * I.e. every single order of X, Y, Z says ps2 is behind ps or they overlap.
 				 * That is: If one partial order says ps behind ps2, do not change the order.
 				 */
-				if (ps->xmax < ps2->xmin) {
-					/* all following sprites have xmin >= ps2->xmin */
-					break;
-				}
-				if (ps->ymax < ps2->ymin || ps->zmax < ps2->zmin) {
+				if (ps->xmax < ps2->xmin ||
+						ps->ymax < ps2->ymin ||
+						ps->zmax < ps2->zmin) {
 					continue;
 				}
 			}
diff --git a/src/viewport_sprite_sorter_sse4.cpp b/src/viewport_sprite_sorter_sse4.cpp
--- a/src/viewport_sprite_sorter_sse4.cpp
+++ b/src/viewport_sprite_sorter_sse4.cpp
@@ -15,7 +15,6 @@
 #include "cpu.h"
 #include "smmintrin.h"
 #include "viewport_sprite_sorter.h"
-#include "core/sort_func.hpp"
 
 #include "safeguards.h"
 
@@ -26,24 +25,12 @@
 	#define LOAD_128 _mm_loadu_si128
 #endif
 
-static int CDECL CompareParentSprites(ParentSpriteToDraw * const *psd, ParentSpriteToDraw * const *psd2)
-{
-	const ParentSpriteToDraw *ps = *psd;
-	const ParentSpriteToDraw *ps2 = *psd2;
-	return ps->xmin - ps2->xmin;
-}
-
 /** Sort parent sprites pointer array using SSE4.1 optimizations. */
 void ViewportSortParentSpritesSSE41(ParentSpriteToSortVector *psdv)
 {
-	const __m128i mask_ptest  = _mm_setr_epi8(-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,  0,  0,  0,  0);
-	const __m128i mask_ptest2 = _mm_setr_epi8(-1, -1, -1, -1,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0);
+	const __m128i mask_ptest = _mm_setr_epi8(-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,  0,  0,  0,  0);
 	ParentSpriteToDraw ** const psdvend = psdv->End();
 	ParentSpriteToDraw **psd = psdv->Begin();
-
-	/* pre-sort by xmin in ascending order */
-	QSortT(psd, psdvend - psd, CompareParentSprites);
-
 	while (psd != psdvend) {
 		ParentSpriteToDraw * const ps = *psd;
 
@@ -77,14 +64,8 @@ void ViewportSortParentSpritesSSE41(Pare
 			__m128i ps1_max = LOAD_128((__m128i*) &ps->xmax);
 			__m128i ps2_min = LOAD_128((__m128i*) &ps2->xmin);
 			__m128i rslt1 = _mm_cmplt_epi32(ps1_max, ps2_min);
-			if (!_mm_testz_si128(mask_ptest, rslt1)) {
-				if (!_mm_testz_si128(mask_ptest2, rslt1) /* ps->xmax < ps2->xmin */) {
-					/* all following sprites have xmin >= ps2->xmin */
-					break;
-				} else {
-					continue;
-				}
-			}
+			if (!_mm_testz_si128(mask_ptest, rslt1))
+				continue;
 
 			__m128i ps1_min = LOAD_128((__m128i*) &ps->xmin);
 			__m128i ps2_max = LOAD_128((__m128i*) &ps2->xmax);