From 5df01a91707aa74b984cb35417d7ca8f7ee4cf8e Mon Sep 17 00:00:00 2001
From: Emmanouil Papadeas <35376950+OverloadedOrama@users.noreply.github.com>
Date: Mon, 10 Feb 2025 20:15:45 +0200
Subject: [PATCH] Users can now add custom dithering matrix images

Not exposed somewhere in the UI yet, but users can now add custom dithering pattern as images in "user://dither_matrices". Right now only used for gradient generation.
---
 src/Classes/ShaderLoader.gd                   | 24 +++++++++++++++++++
 src/Main.gd                                   |  6 +++++
 src/UI/Dialogs/ImageEffects/GradientDialog.gd | 21 +++-------------
 3 files changed, 33 insertions(+), 18 deletions(-)

diff --git a/src/Classes/ShaderLoader.gd b/src/Classes/ShaderLoader.gd
index f749362c4..5f2b58c6c 100644
--- a/src/Classes/ShaderLoader.gd
+++ b/src/Classes/ShaderLoader.gd
@@ -6,6 +6,30 @@ const BASIS_SLIDERS_TSCN := preload("res://src/UI/Nodes/Sliders/BasisSliders.tsc
 const GRADIENT_EDIT_TSCN := preload("res://src/UI/Nodes/GradientEdit.tscn")
 const NOISE_GENERATOR := preload("res://src/UI/Nodes/NoiseGeneratorDialog.tscn")
 
+static var dither_matrices: Array[DitherMatrix] = [
+	DitherMatrix.new(preload("res://assets/dither-matrices/bayer2.png"), "Bayer 2x2"),
+	DitherMatrix.new(preload("res://assets/dither-matrices/bayer4.png"), "Bayer 4x4"),
+	DitherMatrix.new(preload("res://assets/dither-matrices/bayer8.png"), "Bayer 8x8"),
+	DitherMatrix.new(preload("res://assets/dither-matrices/bayer16.png"), "Bayer 16x16"),
+]
+
+
+class DitherMatrix:
+	var texture: Texture2D
+	var name: String
+
+	func _init(_texture: Texture2D, _name: String) -> void:
+		texture = _texture
+		name = _name
+
+
+static func load_dither_matrix_from_file(file_path: String) -> void:
+	var dither_image := Image.load_from_file(file_path)
+	if is_instance_valid(dither_image):
+		var dither_tex := ImageTexture.create_from_image(dither_image)
+		var dither_matrix := DitherMatrix.new(dither_tex, file_path.get_file().get_basename())
+		dither_matrices.append(dither_matrix)
+
 
 static func create_ui_for_shader_uniforms(
 	shader: Shader,
diff --git a/src/Main.gd b/src/Main.gd
index e98439a2a..ba370bd2c 100644
--- a/src/Main.gd
+++ b/src/Main.gd
@@ -169,6 +169,12 @@ func _init() -> void:
 		DirAccess.make_dir_recursive_absolute("user://backups")
 	Global.shrink = _get_auto_display_scale()
 	_handle_layout_files()
+	# Load dither matrix images.
+	var dither_matrices_path := "user://dither_matrices"
+	if DirAccess.dir_exists_absolute(dither_matrices_path):
+		for file_name in DirAccess.get_files_at(dither_matrices_path):
+			var file_path := dither_matrices_path.path_join(file_name)
+			ShaderLoader.load_dither_matrix_from_file(file_path)
 
 
 func _ready() -> void:
diff --git a/src/UI/Dialogs/ImageEffects/GradientDialog.gd b/src/UI/Dialogs/ImageEffects/GradientDialog.gd
index a49dcc29b..2652b82fc 100644
--- a/src/UI/Dialogs/ImageEffects/GradientDialog.gd
+++ b/src/UI/Dialogs/ImageEffects/GradientDialog.gd
@@ -7,13 +7,7 @@ var shader_linear := preload("res://src/Shaders/Effects/Gradients/Linear.gdshade
 var shader_linear_dither := preload("res://src/Shaders/Effects/Gradients/LinearDithering.gdshader")
 
 var shader := shader_linear
-var dither_matrices: Array[DitherMatrix] = [
-	DitherMatrix.new(preload("res://assets/dither-matrices/bayer2.png"), "Bayer 2x2"),
-	DitherMatrix.new(preload("res://assets/dither-matrices/bayer4.png"), "Bayer 4x4"),
-	DitherMatrix.new(preload("res://assets/dither-matrices/bayer8.png"), "Bayer 8x8"),
-	DitherMatrix.new(preload("res://assets/dither-matrices/bayer16.png"), "Bayer 16x16"),
-]
-var selected_dither_matrix := dither_matrices[0]
+var selected_dither_matrix := ShaderLoader.dither_matrices[0]
 
 @onready var options_cont: Container = $VBoxContainer/GradientOptions
 @onready var gradient_edit: GradientEditNode = $VBoxContainer/GradientEdit
@@ -27,22 +21,13 @@ var selected_dither_matrix := dither_matrices[0]
 @onready var radius_slider := $"%RadiusSlider" as ValueSliderV2
 
 
-class DitherMatrix:
-	var texture: Texture2D
-	var name: String
-
-	func _init(_texture: Texture2D, _name: String) -> void:
-		texture = _texture
-		name = _name
-
-
 func _ready() -> void:
 	super._ready()
 	var sm := ShaderMaterial.new()
 	sm.shader = shader
 	preview.set_material(sm)
 
-	for matrix in dither_matrices:
+	for matrix in ShaderLoader.dither_matrices:
 		dithering_option_button.add_item(matrix.name)
 
 	# Set as in the Animate enum
@@ -140,7 +125,7 @@ func _value_v2_changed(_value: Vector2) -> void:
 func _on_DitheringOptionButton_item_selected(index: int) -> void:
 	if index > 0:
 		shader = shader_linear_dither
-		selected_dither_matrix = dither_matrices[index - 1]
+		selected_dither_matrix = ShaderLoader.dither_matrices[index - 1]
 	else:
 		shader = shader_linear
 	update_preview()