Add a convolution matrix layer effect

Still WIP, could use some extra parameters such as RGBA channel, and I should also implement it as an image effect.

src/Autoload/Global.gd

@@ -118,6 +118,7 @@ const CONFIG_SUBDIR_NAME := "pixelorama_data"
 ## The path of the directory where the UI layouts are being stored.
 const LAYOUT_DIR := "user://layouts"
 const VALUE_SLIDER_V2_TSCN := preload("res://src/UI/Nodes/ValueSliderV2.tscn")
+const BASIS_SLIDERS_TSCN := preload("res://src/UI/Nodes/BasisSliders.tscn")
 const GRADIENT_EDIT_TSCN := preload("res://src/UI/Nodes/GradientEdit.tscn")
 
 ## It is path to the executable's base drectory.
@@ -1214,6 +1215,25 @@ func create_ui_for_shader_uniforms(
 				hbox.add_child(label)
 				hbox.add_child(color_button)
 				parent_node.add_child(hbox)
+		elif u_type == "mat3":
+			var label := Label.new()
+			label.text = humanized_u_name
+			label.size_flags_horizontal = Control.SIZE_EXPAND_FILL
+			var basis := _mat3str_to_basis(u_value)
+			var sliders := BASIS_SLIDERS_TSCN.instantiate() as BasisSliders
+			sliders.allow_greater = true
+			sliders.allow_lesser = true
+			sliders.size_flags_horizontal = Control.SIZE_EXPAND_FILL
+			sliders.value = basis
+			if params.has(u_name):
+				sliders.value = params[u_name]
+			else:
+				params[u_name] = sliders.value
+			sliders.value_changed.connect(value_changed.bind(u_name))
+			var hbox := HBoxContainer.new()
+			hbox.add_child(label)
+			hbox.add_child(sliders)
+			parent_node.add_child(hbox)
 		elif u_type == "sampler2D":
 			if u_name == "selection":
 				continue
@@ -1299,6 +1319,24 @@ func _vec2str_to_vector2(vec2: String) -> Vector2:
 	return vector2
 
 
+func _vec3str_to_vector3(vec3: String) -> Vector3:
+	vec3 = vec3.replace("uvec3", "vec3")
+	vec3 = vec3.replace("ivec3", "vec3")
+	vec3 = vec3.replace("vec3(", "")
+	vec3 = vec3.replace(")", "")
+	var vec_values := vec3.split(",")
+	if vec_values.size() == 0:
+		return Vector3.ZERO
+	var y := float(vec_values[0])
+	var z := float(vec_values[0])
+	if vec_values.size() >= 2:
+		y = float(vec_values[1])
+	if vec_values.size() == 3:
+		z = float(vec_values[2])
+	var vector3 := Vector3(float(vec_values[0]), y, z)
+	return vector3
+
+
 func _vec4str_to_color(vec4: String) -> Color:
 	vec4 = vec4.replace("vec4(", "")
 	vec4 = vec4.replace(")", "")
@@ -1320,6 +1358,24 @@ func _vec4str_to_color(vec4: String) -> Color:
 	return color
 
 
+func _mat3str_to_basis(mat3: String) -> Basis:
+	mat3 = mat3.replace("mat3(", "")
+	mat3 = mat3.replace("))", ")")
+	mat3 = mat3.replace("), ", ")")
+	var vec3_values := mat3.split("vec3", false)
+	var vec3_x := _vec3str_to_vector3(vec3_values[0])
+
+	var vec3_y := _vec3str_to_vector3(vec3_values[0])
+	if vec3_values.size() >= 2:
+		vec3_y = _vec3str_to_vector3(vec3_values[1])
+
+	var vec3_z := _vec3str_to_vector3(vec3_values[0])
+	if vec3_values.size() == 3:
+		vec3_z = _vec3str_to_vector3(vec3_values[2])
+	var basis := Basis(vec3_x, vec3_y, vec3_z)
+	return basis
+
+
 func _shader_change_palette(value_changed: Callable, parameter_name: String) -> void:
 	var palette := Palettes.current_palette
 	_shader_update_palette_texture(palette, value_changed, parameter_name)

src/Shaders/Effects/ConvolutionMatrix.gdshader

@@ -0,0 +1,82 @@
+shader_type canvas_item;
+
+// author : csblo
+// Work made just by consulting :
+// https://en.wikipedia.org/wiki/Kernel_(image_processing)
+
+uniform mat3 kernel = mat3(vec3(0, 0, 0), vec3(0, 1, 0), vec3(0, 0, 0));
+
+// Find coordinate of matrix element from index
+vec2 kpos(int index, vec2 iResolution)
+{
+	return vec2[9] (
+		vec2(-1, -1), vec2(0, -1), vec2(1, -1),
+		vec2(-1, 0), vec2(0, 0), vec2(1, 0),
+		vec2(-1, 1), vec2(0, 1), vec2(1, 1)
+	)[index] / iResolution.xy;
+}
+
+
+// Extract region of dimension 3x3 from sampler centered in uv
+// sampler : texture sampler
+// uv : current coordinates on sampler
+// return : an array of mat3, each index corresponding with a color channel
+mat3[3] region3x3(sampler2D sampler, vec2 uv, vec2 iResolution)
+{
+	// Create each pixels for region
+	vec4[9] region;
+
+	for (int i = 0; i < 9; i++)
+		region[i] = texture(sampler, uv + kpos(i, iResolution));
+
+	// Create 3x3 region with 3 color channels (red, green, blue)
+	mat3[3] mRegion;
+
+	for (int i = 0; i < 3; i++)
+		mRegion[i] = mat3(
+			vec3(region[0][i], region[1][i], region[2][i]),
+			vec3(region[3][i], region[4][i], region[5][i]),
+			vec3(region[6][i], region[7][i], region[8][i])
+		);
+
+	return mRegion;
+}
+
+// Convolve a texture with kernel
+// kernel : kernel used for convolution
+// sampler : texture sampler
+// uv : current coordinates on sampler
+vec3 convolution(sampler2D sampler, vec2 uv, vec2 iResolution)
+{
+	vec3 fragment;
+
+	// Extract a 3x3 region centered in uv
+	mat3[3] region = region3x3(sampler, uv, iResolution);
+
+	// for each color channel of region
+	for (int i = 0; i < 3; i++)
+	{
+		// get region channel
+		mat3 rc = region[i];
+		// component wise multiplication of kernel by region channel
+		mat3 c = matrixCompMult(kernel, rc);
+		// add each component of matrix
+		float r = c[0][0] + c[1][0] + c[2][0]
+				+ c[0][1] + c[1][1] + c[2][1]
+				+ c[0][2] + c[1][2] + c[2][2];
+
+		// for fragment at channel i, set result
+		fragment[i] = r;
+	}
+
+	return fragment;
+}
+
+void fragment()
+{
+	// Convolve kernel with texture
+	vec3 col = convolution(TEXTURE, UV, 1.0 / TEXTURE_PIXEL_SIZE);
+
+	// Output to screen
+	COLOR.rgb = col;
+}

src/UI/Nodes/BasisSliders.gd

@@ -0,0 +1,65 @@
+@tool
+class_name BasisSliders
+extends HBoxContainer
+
+signal value_changed(value: Basis)
+
+@export var value: Basis:
+	set(val):
+		value = val
+		_can_emit_signal = false
+		get_sliders()[0].value = value.x
+		get_sliders()[1].value = value.y
+		get_sliders()[2].value = value.z
+		_can_emit_signal = true
+@export var min_value := Vector3.ZERO:
+	set(val):
+		min_value = val
+		get_sliders()[0].min_value = val
+		get_sliders()[1].min_value = val
+		get_sliders()[2].min_value = val
+@export var max_value := Vector3(100.0, 100.0, 100.0):
+	set(val):
+		max_value = val
+		get_sliders()[0].max_value = val
+		get_sliders()[1].max_value = val
+		get_sliders()[2].max_value = val
+@export var step := 1.0:
+	set(val):
+		step = val
+		for slider in get_sliders():
+			slider.step = val
+@export var allow_greater := false:
+	set(val):
+		allow_greater = val
+		for slider in get_sliders():
+			slider.allow_greater = val
+@export var allow_lesser := false:
+	set(val):
+		allow_lesser = val
+		for slider in get_sliders():
+			slider.allow_lesser = val
+
+var _can_emit_signal := true
+
+
+func get_sliders() -> Array[ValueSliderV3]:
+	return [$XSlider, $YSlider, $ZSlider]
+
+
+func _on_x_slider_value_changed(val: Vector3) -> void:
+	value.x = val
+	if _can_emit_signal:
+		value_changed.emit(value)
+
+
+func _on_y_slider_value_changed(val: Vector3) -> void:
+	value.y = val
+	if _can_emit_signal:
+		value_changed.emit(value)
+
+
+func _on_z_slider_value_changed(val: Vector3) -> void:
+	value.z = val
+	if _can_emit_signal:
+		value_changed.emit(value)

src/UI/Nodes/BasisSliders.tscn

@@ -0,0 +1,40 @@
+[gd_scene load_steps=3 format=3 uid="uid://d0d66oh6bw3kt"]
+
+[ext_resource type="Script" path="res://src/UI/Nodes/BasisSliders.gd" id="1_sbf5t"]
+[ext_resource type="PackedScene" uid="uid://dpoteid430evf" path="res://src/UI/Nodes/ValueSliderV3.tscn" id="2_7swri"]
+
+[node name="BasisSliders" type="HBoxContainer"]
+offset_right = 40.0
+offset_bottom = 40.0
+script = ExtResource("1_sbf5t")
+
+[node name="XSlider" parent="." instance=ExtResource("2_7swri")]
+layout_mode = 2
+size_flags_horizontal = 3
+value = Vector3(1, 0, 0)
+slider_min_size = Vector2(64, 24)
+prefix_x = "XX:"
+prefix_y = "YX:"
+prefix_z = "ZX:"
+
+[node name="YSlider" parent="." instance=ExtResource("2_7swri")]
+layout_mode = 2
+size_flags_horizontal = 3
+value = Vector3(0, 1, 0)
+slider_min_size = Vector2(64, 24)
+prefix_x = "XY:"
+prefix_y = "YY:"
+prefix_z = "ZY:"
+
+[node name="ZSlider" parent="." instance=ExtResource("2_7swri")]
+layout_mode = 2
+size_flags_horizontal = 3
+value = Vector3(0, 0, 1)
+slider_min_size = Vector2(64, 24)
+prefix_x = "XZ:"
+prefix_y = "YZ:"
+prefix_z = "ZZ:"
+
+[connection signal="value_changed" from="XSlider" to="." method="_on_x_slider_value_changed"]
+[connection signal="value_changed" from="YSlider" to="." method="_on_y_slider_value_changed"]
+[connection signal="value_changed" from="ZSlider" to="." method="_on_z_slider_value_changed"]

src/UI/Nodes/ValueSliderV3.gd

@@ -4,8 +4,8 @@ extends HBoxContainer
 ## A class that combines three ValueSlider nodes, for easy usage with Vector3 values.
 ## Also supports aspect ratio locking.
 
-signal value_changed(value)
+signal value_changed(value: Vector3)
-signal ratio_toggled(button_pressed)
+signal ratio_toggled(button_pressed: bool)
 
 @export var editable := true:
 	set(val):

src/UI/Nodes/ValueSliderV3.tscn

@@ -1,86 +1,83 @@
-[gd_scene load_steps=6 format=2]
+[gd_scene load_steps=6 format=3 uid="uid://dpoteid430evf"]
 
-[ext_resource path="res://src/UI/Nodes/ValueSlider.gd" type="Script" id=1]
+[ext_resource type="Script" path="res://src/UI/Nodes/ValueSlider.gd" id="1"]
-[ext_resource path="res://src/UI/Nodes/ValueSliderV3.gd" type="Script" id=2]
+[ext_resource type="Script" path="res://src/UI/Nodes/ValueSliderV3.gd" id="2"]
-[ext_resource path="res://assets/graphics/misc/lock_aspect_2.png" type="Texture2D" id=3]
+[ext_resource type="Texture2D" uid="uid://cancw70yw0pv7" path="res://assets/graphics/misc/lock_aspect_2.png" id="3"]
-[ext_resource path="res://assets/graphics/misc/lock_aspect_guides.png" type="Texture2D" id=4]
+[ext_resource type="Texture2D" uid="uid://kd10jfc1dxf5" path="res://assets/graphics/misc/lock_aspect_guides.png" id="4"]
-[ext_resource path="res://assets/graphics/misc/lock_aspect.png" type="Texture2D" id=5]
+[ext_resource type="Texture2D" uid="uid://beqermx8s5q8y" path="res://assets/graphics/misc/lock_aspect.png" id="5"]
 
 [node name="ValueSliderV3" type="HBoxContainer"]
 offset_right = 45.0
 offset_bottom = 52.0
-script = ExtResource( 2 )
+script = ExtResource("2")
 
 [node name="GridContainer" type="GridContainer" parent="."]
-offset_right = 45.0
+layout_mode = 2
-offset_bottom = 80.0
 size_flags_horizontal = 3
 
 [node name="X" type="TextureProgressBar" parent="GridContainer"]
-offset_right = 45.0
+custom_minimum_size = Vector2(32, 24)
-offset_bottom = 24.0
+layout_mode = 2
-custom_minimum_size = Vector2( 32, 24 )
-mouse_default_cursor_shape = 2
 size_flags_horizontal = 3
-theme_type_variation = "ValueSlider"
+focus_mode = 2
+mouse_default_cursor_shape = 2
+theme_type_variation = &"ValueSlider"
 nine_patch_stretch = true
 stretch_margin_left = 3
 stretch_margin_top = 3
 stretch_margin_right = 3
 stretch_margin_bottom = 3
-script = ExtResource( 1 )
+script = ExtResource("1")
 prefix = "X:"
 
 [node name="Y" type="TextureProgressBar" parent="GridContainer"]
-offset_top = 28.0
+custom_minimum_size = Vector2(32, 24)
-offset_right = 45.0
+layout_mode = 2
-offset_bottom = 52.0
-custom_minimum_size = Vector2( 32, 24 )
-mouse_default_cursor_shape = 2
 size_flags_horizontal = 3
-theme_type_variation = "ValueSlider"
+focus_mode = 2
+mouse_default_cursor_shape = 2
+theme_type_variation = &"ValueSlider"
 nine_patch_stretch = true
 stretch_margin_left = 3
 stretch_margin_top = 3
 stretch_margin_right = 3
 stretch_margin_bottom = 3
-script = ExtResource( 1 )
+script = ExtResource("1")
 prefix = "Y:"
 
 [node name="Z" type="TextureProgressBar" parent="GridContainer"]
-offset_top = 56.0
+custom_minimum_size = Vector2(32, 24)
-offset_right = 45.0
+layout_mode = 2
-offset_bottom = 80.0
-custom_minimum_size = Vector2( 32, 24 )
-mouse_default_cursor_shape = 2
 size_flags_horizontal = 3
-theme_type_variation = "ValueSlider"
+focus_mode = 2
+mouse_default_cursor_shape = 2
+theme_type_variation = &"ValueSlider"
 nine_patch_stretch = true
 stretch_margin_left = 3
 stretch_margin_top = 3
 stretch_margin_right = 3
 stretch_margin_bottom = 3
-script = ExtResource( 1 )
+script = ExtResource("1")
 prefix = "Z:"
 
 [node name="Ratio" type="Control" parent="."]
 visible = false
-offset_left = 36.0
+custom_minimum_size = Vector2(16, 0)
-offset_right = 52.0
+layout_mode = 2
-offset_bottom = 80.0
-custom_minimum_size = Vector2( 16, 0 )
 
 [node name="RatioGuides" type="NinePatchRect" parent="Ratio" groups=["UIButtons"]]
+custom_minimum_size = Vector2(9, 0)
+layout_mode = 0
 anchor_bottom = 1.0
 offset_right = 9.0
-custom_minimum_size = Vector2( 9, 0 )
+texture = ExtResource("4")
-texture = ExtResource( 4 )
+region_rect = Rect2(0, 0, 9, 44)
-region_rect = Rect2( 0, 0, 9, 44 )
 patch_margin_top = 15
 patch_margin_bottom = 13
 
 [node name="RatioButton" type="TextureButton" parent="Ratio" groups=["UIButtons"]]
 unique_name_in_owner = true
+layout_mode = 0
 anchor_left = 0.5
 anchor_top = 0.5
 anchor_right = 0.5
@@ -92,8 +89,8 @@ offset_bottom = 8.0
 tooltip_text = "Lock aspect ratio"
 mouse_default_cursor_shape = 2
 toggle_mode = true
-texture_normal = ExtResource( 3 )
+texture_normal = ExtResource("3")
-texture_pressed = ExtResource( 5 )
+texture_pressed = ExtResource("5")
 
 [connection signal="value_changed" from="GridContainer/X" to="." method="_on_X_value_changed"]
 [connection signal="value_changed" from="GridContainer/Y" to="." method="_on_Y_value_changed"]

src/UI/Timeline/LayerEffects/LayerEffectsSettings.gd

@@ -4,6 +4,9 @@ const LAYER_EFFECT_BUTTON = preload("res://src/UI/Timeline/LayerEffects/LayerEff
 const DELETE_TEXTURE := preload("res://assets/graphics/misc/close.svg")
 
 var effects: Array[LayerEffect] = [
+	LayerEffect.new(
+		"Convolution Matrix", preload("res://src/Shaders/Effects/ConvolutionMatrix.gdshader")
+	),
 	LayerEffect.new("Offset", preload("res://src/Shaders/Effects/OffsetPixels.gdshader")),
 	LayerEffect.new("Outline", preload("res://src/Shaders/Effects/OutlineInline.gdshader")),
 	LayerEffect.new("Drop Shadow", preload("res://src/Shaders/Effects/DropShadow.gdshader")),