added brush and implemented opacity size and hardness

Assets/Scenes/SampleScene.unity

@@ -671,7 +671,7 @@ MonoBehaviour:
   m_MinValue: 0
   m_MaxValue: 1
   m_WholeNumbers: 0
-  m_Value: 0
+  m_Value: 1
   m_OnValueChanged:
     m_PersistentCalls:
       m_Calls: []
@@ -1405,7 +1405,7 @@ MonoBehaviour:
   m_MinValue: 0
   m_MaxValue: 1
   m_WholeNumbers: 0
-  m_Value: 0
+  m_Value: 0.5
   m_OnValueChanged:
     m_PersistentCalls:
       m_Calls: []
@@ -2059,6 +2059,7 @@ MonoBehaviour:
   m_Name: 
   m_EditorClassIdentifier: 
   ColorPickerShader: {fileID: 4800000, guid: b27fa81f06a9f23438866297617dfde2, type: 3}
+  brushShader: {fileID: 4800000, guid: 04eb8c138cbd7fc43a8aa07ac9d9760e, type: 3}
 --- !u!1 &1902939436
 GameObject:
   m_ObjectHideFlags: 0
@@ -2319,7 +2320,7 @@ MonoBehaviour:
   m_MinValue: 0
   m_MaxValue: 1
   m_WholeNumbers: 0
-  m_Value: 0
+  m_Value: 0.5
   m_OnValueChanged:
     m_PersistentCalls:
       m_Calls: []

Assets/Scripts/BrushShader.shader

@@ -0,0 +1,70 @@
+Shader "Unlit/BrushShader"
+{
+	Properties
+	{
+		_MainTex("Texture", 2D) = "white" {}
+
+	}
+		SubShader
+	{
+		Tags{ "RenderType" = "Transparent" "Queue" = "Transparent" }
+		ZWrite Off
+		Cull Off
+		Blend SrcAlpha OneMinusSrcAlpha
+		LOD 100
+
+		Pass
+	{
+		CGPROGRAM
+#pragma vertex vert
+#pragma fragment frag
+
+#include "UnityCG.cginc"
+
+		struct appdata
+	{
+		float4 vertex : POSITION;
+		float2 uv : TEXCOORD0;
+	};
+
+	struct v2f
+	{
+		float2 uv : TEXCOORD0;
+			float4 vertex : SV_POSITION;
+		float4 proj : TEXCOORD2;
+	};
+
+	sampler2D _MainTex;
+	float4 _MainTex_ST;
+	sampler2D_float _CameraDepthTexture;
+	float4 _Color;
+	v2f vert(appdata v)
+	{
+		v2f o;
+		o.vertex = UnityObjectToClipPos(v.vertex);
+		o.proj = ComputeScreenPos(o.vertex);
+		COMPUTE_EYEDEPTH(o.proj.z);
+		//Use this for linear one                        
+		//o.proj.z = COMPUTE_DEPTH_01;
+		o.uv = TRANSFORM_TEX(v.uv, _MainTex);
+
+		return o;
+	}
+
+	fixed4 frag(v2f i) : SV_Target
+	{
+		// sample the texture
+		fixed4 col = tex2D(_MainTex, i.uv);
+	float depth = LinearEyeDepth(SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture, i.proj.xy / i.proj.w));
+
+	float a = saturate(depth - i.proj.z);
+	a = smoothstep(0., 0.2, a);
+	a = 1. - a;
+	a = pow(a, 10.);
+	col.a *= a;
+	return col* _Color;
+	}
+		ENDCG
+	}
+	}
+}

Assets/Scripts/InputUIManager.cs

@@ -8,6 +8,7 @@ public class InputUIManager : MonoBehaviour, IPointerClickHandler, IDragHandler
 {
 
     public Shader ColorPickerShader;
+    public Shader brushShader;
 
     private RawImage valueSaturationPicker;
     private RawImage huePicker;
@@ -16,13 +17,24 @@ public class InputUIManager : MonoBehaviour, IPointerClickHandler, IDragHandler
 
     private Button switchButton;
 
+    private Slider opacitySlider;
+    private Slider sizeSlider;
+    private Slider hardnessSlider;
+
+
     private GameObject[] allUIElements;
     private RenderTexture valueSaturationImage;
     private RenderTexture huePickerImage;
     private Material mColorPicker;
 
-    private Vector3 ColorPickerCurrentHSV = new Vector3(1f, 1f, 0.5f);
+    private GameObject mouseRepresentation;
+    private GameObject mouseHardnessRepresentation;
+    private Material mouseMaterial;
+    private Material mouseSoftnessMaterial;
 
+    private Vector3 ColorPickerCurrentHSV = new Vector3(1f, 1f, 0.5f);
+    private float brushSize;
+    private float brushHardness;
 
 
     void OnDisable()
@@ -57,6 +69,22 @@ void Start ()
         switchButton = InitializeUIElement("SwitchBackForeGround").GetComponent<Button>();
         switchButton.onClick.AddListener(() => buttonCallBack(switchButton));
 
+        opacitySlider = InitializeUIElement("Opacity").GetComponent<Slider>();
+        sizeSlider = InitializeUIElement("Size").GetComponent<Slider>();
+        hardnessSlider = InitializeUIElement("Hardness").GetComponent<Slider>();
+
+
+        mouseRepresentation = GameObject.CreatePrimitive(PrimitiveType.Sphere);
+        mouseRepresentation.GetComponent<SphereCollider>().enabled = false;
+        mouseMaterial = new Material(brushShader);
+
+        mouseRepresentation.GetComponent<Renderer>().material = mouseMaterial;
+
+        mouseSoftnessMaterial = new Material(brushShader);
+        mouseHardnessRepresentation = GameObject.CreatePrimitive(PrimitiveType.Sphere);
+        mouseHardnessRepresentation.GetComponent<SphereCollider>().enabled = false;
+        mouseHardnessRepresentation.GetComponent<Renderer>().material = mouseSoftnessMaterial;
+
     }
 
 	// Update is called once per frame
@@ -71,7 +99,23 @@ void Update () {
         Graphics.Blit(Texture2D.whiteTexture, huePickerImage, mColorPicker, 1);
 
         Shader.SetGlobalColor("_BrushColor", foreground.color);
+
+        Shader.SetGlobalFloat("_BrushOpacity", opacitySlider.value);
+        brushSize = sizeSlider.value * .6f;
+        Shader.SetGlobalFloat("_BrushSize", brushSize);
+        brushHardness = hardnessSlider.value;
+        Shader.SetGlobalFloat("_BrushHardness", brushHardness);
+
+        if (TexturePaint.mouseWorldPosition.x == Mathf.Infinity) mouseRepresentation.transform.position = new Vector3(1000f, 1000f, 1000f);
+        else mouseRepresentation.transform.position = TexturePaint.mouseWorldPosition;
+        mouseRepresentation.transform.localScale = new Vector3(brushSize*2.0f, brushSize * 2.0f, brushSize * 2.0f);
+
+        mouseHardnessRepresentation.transform.position = mouseRepresentation.transform.position;
+        mouseHardnessRepresentation.transform.localScale = mouseRepresentation.transform.localScale * brushHardness;
 
+
+        mouseMaterial.SetColor("_Color", foreground.color);
+        mouseSoftnessMaterial.SetColor("_Color", new Color(1f-foreground.color.r, 1f - foreground.color.g, 1f - foreground.color.b));
     }
 
     private GameObject InitializeUIElement(string name)
@@ -124,6 +168,7 @@ public void OnPointerClick(PointerEventData eventData)
 
     public void OnDrag(PointerEventData eventData)
     {
+        if (eventData.pointerCurrentRaycast.gameObject == null) return;
         string objectName = eventData.pointerCurrentRaycast.gameObject.name;
 
         switch (objectName)
@@ -154,6 +199,23 @@ private void buttonCallBack(Button buttonPressed)
         }
     }
 
+    private void sliderCallBack(float value, Slider s)
+    {
+        string nameOfSlider = s.gameObject.name;
+        switch (nameOfSlider)
+        {
+            case "Opacity":
+
+                break;
+            case "Size":
+
+                break;
+            case "Hardness":
+
+                break;
+        }
+    }
+
 
 
 }

Assets/Scripts/TexturePaint.cs

@@ -14,6 +14,8 @@ public class TexturePaint : MonoBehaviour {
     public RenderTexture runTimeTexture;               // the actual shader the stuff are going to be drawn to
     public Mesh          meshToDraw;
 
+    public static Vector3 mouseWorldPosition;
+
     // --------------------------------
     private Material        m;                          // material which the UV shader is binded to
     private CommandBuffer   cb;                         // commandbuffer used to run the UV shader on camera event
@@ -84,7 +86,7 @@ private void Update()
 
         mwp.w = Input.GetMouseButton(0)? 1 : 0;
 
-
+        mouseWorldPosition = mwp;
         Shader.SetGlobalVector("_Mouse", mwp);
         m.SetMatrix("mesh_Object2World", meshGameobject.transform.localToWorldMatrix);
 

Assets/Scripts/TexturePaint.shader

@@ -42,6 +42,9 @@
 			float4x4  mesh_Object2World;
 			sampler2D _MainTex;
 			float4 _BrushColor;
+			float _BrushOpacity;
+			float _BrushHardness;
+			float _BrushSize;
 
 			// =====================================================================================================================
 			// VERTEX FRAGMENT ----------------------------------
@@ -64,10 +67,12 @@
 			fixed4 frag (v2f i) : SV_Target
 			{
 				float4 col  = tex2D(_MainTex, i.uv);
+				float  size = _BrushSize;
+				float  soft = _BrushHardness;
 				float  f	= distance(_Mouse.xyz, i.worldPos);
-					   f    = 1.-smoothstep(0., 0.02, f);
+					   f    = 1.-smoothstep(size*soft, size, f);
 
-					   col  = lerp(col, _BrushColor, f * _Mouse.w);
+					   col  = lerp(col, _BrushColor, f * _Mouse.w * _BrushOpacity);
 					   col  = saturate(col);
 
 				return col;