From 71c5b830fd4ce57f4562ff44ee2fe2029f925493 Mon Sep 17 00:00:00 2001
From: Tim Sarbin <tim.sarbin@gmail.com>
Date: Fri, 1 Nov 2019 22:41:49 -0400
Subject: [PATCH] Fixed more rendering issues.

---
 Common/Math.go |  6 ++++++
 Core/Engine.go |  1 +
 Map/Engine.go  | 50 +++++++++++++++++++++++++++++++-------------------
 config.json    |  2 +-
 main.go        |  4 ++++
 5 files changed, 43 insertions(+), 20 deletions(-)

diff --git a/Common/Math.go b/Common/Math.go
index f2c8894e..023acfed 100644
--- a/Common/Math.go
+++ b/Common/Math.go
@@ -52,3 +52,9 @@ func BytesToInt32(b []byte) int32 {
 	// equivalnt of return int32(binary.LittleEndian.Uint32(b))
 	return int32(uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24)
 }
+
+func IsoToScreen(isoX, isoY, modX, modY int) (int, int) {
+	screenX := (isoX - isoY) * 80
+	screenY := (isoX + isoY) * 40
+	return screenX + modX, screenY + modY
+}
diff --git a/Core/Engine.go b/Core/Engine.go
index cba341c0..a17f66cf 100644
--- a/Core/Engine.go
+++ b/Core/Engine.go
@@ -31,6 +31,7 @@ type EngineConfig struct {
 	Scale           float64
 	RunInBackground bool
 	TicksPerSecond  int
+	FpsCap          int
 	VsyncEnabled    bool
 	MpqPath         string
 	MpqLoadOrder    []string
diff --git a/Map/Engine.go b/Map/Engine.go
index 77a89d45..e5241a59 100644
--- a/Map/Engine.go
+++ b/Map/Engine.go
@@ -49,10 +49,13 @@ func (v *Engine) Render(target *ebiten.Image) {
 		offX := -(y * 80)
 		offY := y * 40
 		for x := 0; x < int(v.regions[0].Region.TileWidth); x++ {
-			tile := v.regions[0].Region.DS1.Tiles[y][x]
-			for i := range tile.Floors {
-				if !tile.Floors[i].Hidden && tile.Floors[i].Prop1 != 0 {
-					v.regions[0].Region.RenderTile(offX+int(v.OffsetX), offY+int(v.OffsetY), x, y, RegionLayerTypeFloors, i, target)
+			sx, sy := Common.IsoToScreen(x, y, int(v.OffsetX), int(v.OffsetY))
+			if sx > -160 && sy > -160 && sx <= 800 && sy <= 1000 {
+				tile := v.regions[0].Region.DS1.Tiles[y][x]
+				for i := range tile.Floors {
+					if !tile.Floors[i].Hidden && tile.Floors[i].Prop1 != 0 {
+						v.regions[0].Region.RenderTile(offX+int(v.OffsetX), offY+int(v.OffsetY), x, y, RegionLayerTypeFloors, i, target)
+					}
 				}
 			}
 			offX += 80
@@ -63,12 +66,15 @@ func (v *Engine) Render(target *ebiten.Image) {
 		offX := -(y * 80)
 		offY := y * 40
 		for x := 0; x < int(v.regions[0].Region.TileWidth); x++ {
-			tile := v.regions[0].Region.DS1.Tiles[y][x]
-			for i := range tile.Shadows {
-				if tile.Shadows[i].Hidden || tile.Shadows[i].Prop1 == 0 {
-					continue
+			sx, sy := Common.IsoToScreen(x, y, int(v.OffsetX), int(v.OffsetY))
+			if sx > -160 && sy > -160 && sx <= 800 && sy <= 1000 {
+				tile := v.regions[0].Region.DS1.Tiles[y][x]
+				for i := range tile.Shadows {
+					if tile.Shadows[i].Hidden || tile.Shadows[i].Prop1 == 0 {
+						continue
+					}
+					v.regions[0].Region.RenderTile(offX+int(v.OffsetX), offY+int(v.OffsetY), x, y, RegionLayerTypeShadows, i, target)
 				}
-				v.regions[0].Region.RenderTile(offX+int(v.OffsetX), offY+int(v.OffsetY), x, y, RegionLayerTypeShadows, i, target)
 			}
 			offX += 80
 			offY += 40
@@ -78,12 +84,15 @@ func (v *Engine) Render(target *ebiten.Image) {
 		offX := -(y * 80)
 		offY := y * 40
 		for x := 0; x < int(v.regions[0].Region.TileWidth); x++ {
-			tile := v.regions[0].Region.DS1.Tiles[y][x]
-			for i := range tile.Walls {
-				if tile.Walls[i].Hidden || tile.Walls[i].Orientation == 15 || tile.Walls[i].Orientation == 10 || tile.Walls[i].Orientation == 11 || tile.Walls[i].Orientation == 0 {
-					continue
+			sx, sy := Common.IsoToScreen(x, y, int(v.OffsetX), int(v.OffsetY))
+			if sx > -160 && sy > -160 && sx <= 800 && sy <= 1000 {
+				tile := v.regions[0].Region.DS1.Tiles[y][x]
+				for i := range tile.Walls {
+					if tile.Walls[i].Hidden || tile.Walls[i].Orientation == 15 || tile.Walls[i].Orientation == 10 || tile.Walls[i].Orientation == 11 || tile.Walls[i].Orientation == 0 {
+						continue
+					}
+					v.regions[0].Region.RenderTile(offX+int(v.OffsetX), offY+int(v.OffsetY), x, y, RegionLayerTypeWalls, i, target)
 				}
-				v.regions[0].Region.RenderTile(offX+int(v.OffsetX), offY+int(v.OffsetY), x, y, RegionLayerTypeWalls, i, target)
 			}
 			offX += 80
 			offY += 40
@@ -93,12 +102,15 @@ func (v *Engine) Render(target *ebiten.Image) {
 		offX := -(y * 80)
 		offY := y * 40
 		for x := 0; x < int(v.regions[0].Region.TileWidth); x++ {
-			tile := v.regions[0].Region.DS1.Tiles[y][x]
-			for i := range tile.Walls {
-				if tile.Walls[i].Hidden || tile.Walls[i].Orientation != 15 {
-					continue
+			sx, sy := Common.IsoToScreen(x, y, int(v.OffsetX), int(v.OffsetY))
+			if sx > -160 && sy > -160 && sx <= 800 && sy <= 1000 {
+				tile := v.regions[0].Region.DS1.Tiles[y][x]
+				for i := range tile.Walls {
+					if tile.Walls[i].Hidden || tile.Walls[i].Orientation != 15 {
+						continue
+					}
+					v.regions[0].Region.RenderTile(offX+int(v.OffsetX), offY+int(v.OffsetY), x, y, RegionLayerTypeWalls, i, target)
 				}
-				v.regions[0].Region.RenderTile(offX+int(v.OffsetX), offY+int(v.OffsetY), x, y, RegionLayerTypeWalls, i, target)
 			}
 			offX += 80
 			offY += 40
diff --git a/config.json b/config.json
index 6efa2d72..52573f72 100644
--- a/config.json
+++ b/config.json
@@ -2,7 +2,7 @@
     "Language": "ENG",
     "FullScreen": false,
     "Scale": 1,
-    "TicksPerSecond": 60,
+    "TicksPerSecond": 25,
     "RunInBackground": true,
     "VsyncEnabled": true,
     "SfxVolume": 1.0,
diff --git a/main.go b/main.go
index b38dd85e..5f54d022 100644
--- a/main.go
+++ b/main.go
@@ -2,6 +2,9 @@ package main
 
 import (
 	"log"
+	"strconv"
+
+	"github.com/hajimehoshi/ebiten/ebitenutil"
 
 	"github.com/essial/OpenDiablo2/Core"
 	"github.com/essial/OpenDiablo2/MPQ"
@@ -30,5 +33,6 @@ func update(screen *ebiten.Image) error {
 		return nil
 	}
 	d2Engine.Draw(screen)
+	ebitenutil.DebugPrint(screen, "FPS:"+strconv.Itoa(int(ebiten.CurrentFPS())))
 	return nil
 }