From b8df848f9154278a872a3b2b9f96b67b756e0b7a Mon Sep 17 00:00:00 2001
From: LeeWannacott <WannacottL@gmail.com>
Date: Fri, 13 Oct 2023 23:26:03 +1300
Subject: [PATCH] Feature: added ability to resize each sprite/tile in pixels.

---
 go.mod         |  2 ++
 go.sum         |  2 ++
 main.go        |  7 +++++--
 src/gontage.go | 18 +++++++++++++++---
 4 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/go.mod b/go.mod
index 7bd1917..c1e8ec6 100644
--- a/go.mod
+++ b/go.mod
@@ -1,3 +1,5 @@
 module github.com/LeeWannacott/gontage
 
 go 1.21
+
+require github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646 // direct
diff --git a/go.sum b/go.sum
index e69de29..96adbed 100644
--- a/go.sum
+++ b/go.sum
@@ -0,0 +1,2 @@
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646 h1:zYyBkD/k9seD2A7fsi6Oo2LfFZAehjjQMERAvZLEDnQ=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646/go.mod h1:jpp1/29i3P1S/RLdc7JQKbRpFeM1dOBd8T9ki5s+AY8=
diff --git a/main.go b/main.go
index cac2c13..3575aee 100644
--- a/main.go
+++ b/main.go
@@ -21,6 +21,7 @@ type spritesheet struct {
 	sprite_width      int
 	amount_of_sprites []int
 	hframes           int
+	sprite_resize_px  int
 }
 type folderInfo struct {
 	sub_folder_path         string
@@ -41,6 +42,7 @@ func main() {
 	}
 	sprite_source_folder := flag.String("f", "", "Folder name that contains sprites.")
 	hframes := flag.Int("hframes", 8, "Amount of horizontal sprites you want in your spritesheet: default 8.")
+	sprite_resize_px := flag.Int("sprite_resize", 0, "Resize each tile/sprite in spritesheet to the pixel value provided.")
 	parent_folder_path := flag.String("mf", "", "multiple folders: path should be parent folder containing sub folders that contain folders with sprites/images in them. Refer to test_multi for example structure.")
 	useMontage := flag.Bool("montage", false, "Use montage with -mf instead of gontage (if installed)")
 	help := flag.Bool("h", false, "Display help")
@@ -53,7 +55,7 @@ func main() {
 	}
 
 	if *sprite_source_folder != "" {
-		gontage.Gontage(*sprite_source_folder, hframes)
+		gontage.Gontage(*sprite_source_folder, hframes, *sprite_resize_px)
 	} else {
 		var wg sync.WaitGroup
 		if parent_folder_path != nil {
@@ -78,6 +80,7 @@ func main() {
 					sprite_width:      sprite_width,
 					amount_of_sprites: amount_of_sprites,
 					hframes:           *hframes,
+					sprite_resize_px:  *sprite_resize_px,
 				}
 				cli := cliOptions{
 					useMontage: *useMontage,
@@ -117,7 +120,7 @@ func call_gontage_or_montage(i int, spritesheet spritesheet, folder folderInfo,
 		}
 		fmt.Println(string(out), filepath.Join(folder.sub_folder_path_gontage, folder.folder_name)+"/*", sprite_name)
 	} else {
-		gontage.Gontage(filepath.Join(folder.sub_folder_path_gontage, folder.folder_name), &spritesheet.hframes)
+		gontage.Gontage(filepath.Join(folder.sub_folder_path_gontage, folder.folder_name), &spritesheet.hframes, spritesheet.sprite_resize_px)
 	}
 }
 
diff --git a/src/gontage.go b/src/gontage.go
index 7ba00cf..653604d 100644
--- a/src/gontage.go
+++ b/src/gontage.go
@@ -14,6 +14,8 @@ import (
 	"runtime"
 	"sync"
 	"time"
+
+	"github.com/nfnt/resize"
 )
 
 type drawingInfo struct {
@@ -24,7 +26,7 @@ type drawingInfo struct {
 	spritesheet           draw.Image
 }
 
-func Gontage(sprite_source_folder string, hframes *int) {
+func Gontage(sprite_source_folder string, hframes *int, sprite_resize_px int) {
 	start := time.Now()
 	pwd, err := os.Getwd()
 	if err != nil {
@@ -94,10 +96,20 @@ func Gontage(sprite_source_folder string, hframes *int) {
 		if err != nil {
 			panic(err)
 		}
+
 		encoder := png.Encoder{CompressionLevel: png.BestSpeed}
-		if err = encoder.Encode(f, spritesheet); err != nil {
-			log.Printf("failed to encode: %v", err)
+		if sprite_resize_px != 0 {
+			resized_spritesheet := resize.Resize(uint(*hframes*sprite_resize_px), uint(int(vframes)*sprite_resize_px),
+				spritesheet, resize.Lanczos3)
+			if err = encoder.Encode(f, resized_spritesheet); err != nil {
+				log.Printf("failed to encode: %v", err)
+			}
+		} else {
+			if err = encoder.Encode(f, spritesheet); err != nil {
+				log.Printf("failed to encode: %v", err)
+			}
 		}
+
 		f.Close()
 		fmt.Println(spritesheet_name, ": ", time.Since(start))
 	}