paint tool: redirect alpha

Editor/PaintToolWindow.cpp

@@ -176,6 +176,12 @@ void PaintToolWindow::Create(EditorComponent* _editor)
 	pressureCheckBox.SetCheckText(ICON_PEN);
 	AddWidget(&pressureCheckBox);
 
+	alphaCheckBox.Create("Redirect alpha: ");
+	alphaCheckBox.SetTooltip("The red color will be redirected to write alpha channel. Alpha value controls the blending like normally.");
+	alphaCheckBox.SetSize(XMFLOAT2(hei, hei));
+	alphaCheckBox.SetPos(XMFLOAT2(x - 20 + 200, y));
+	AddWidget(&alphaCheckBox);
+
 	axisCombo.Create("Axis Lock: ");
 	axisCombo.SetTooltip("You can lock modification to an axis here.");
 	axisCombo.SetPos(XMFLOAT2(x, y));
@@ -567,7 +573,7 @@ void PaintToolWindow::Update(float dt)
 					paintparams.push.xPaintBrushAmount = amount;
 					paintparams.push.xPaintBrushSmoothness = smoothness;
 					paintparams.push.xPaintBrushColor = color.rgba;
-					paintparams.push.xPaintReveal = revealTex.IsValid() ? 1 : 0;
+					paintparams.push.xPaintRedirectAlpha = alphaCheckBox.GetCheck();
 					paintparams.push.xPaintBrushRotation = brush_rotation;
 					paintparams.push.xPaintBrushShape = (uint)brushShapeComboBox.GetSelected();
 
@@ -1650,6 +1656,7 @@ void PaintToolWindow::ResizeLayout()
 	add_right(backfaceCheckBox);
 	wireCheckBox.SetPos(XMFLOAT2(backfaceCheckBox.GetPos().x - wireCheckBox.GetSize().x - 100, backfaceCheckBox.GetPos().y));
 	add_right(pressureCheckBox);
+	alphaCheckBox.SetPos(XMFLOAT2(pressureCheckBox.GetPos().x - alphaCheckBox.GetSize().x - 100, pressureCheckBox.GetPos().y));
 	add(textureSlotComboBox);
 	add(brushShapeComboBox);
 	add(axisCombo);

Editor/PaintToolWindow.h

@@ -52,6 +52,7 @@ public:
 	wi::gui::CheckBox backfaceCheckBox;
 	wi::gui::CheckBox wireCheckBox;
 	wi::gui::CheckBox pressureCheckBox;
+	wi::gui::CheckBox alphaCheckBox;
 	wi::gui::ColorPicker colorPicker;
 	wi::gui::ComboBox textureSlotComboBox;
 	wi::gui::ComboBox brushShapeComboBox;

WickedEngine/shaders/ShaderInterop_Renderer.h

@@ -1264,7 +1264,7 @@ struct PaintTexturePushConstants
 
 	float xPaintBrushSmoothness;
 	uint xPaintBrushColor;
-	uint xPaintReveal;
+	uint xPaintRedirectAlpha;
 	float xPaintBrushRotation;
 
 	uint xPaintBrushShape;

WickedEngine/shaders/paint_textureCS.hlsl

@@ -35,7 +35,6 @@ void main( uint3 DTid : SV_DispatchThreadID )
 	}
 	
 	float4 brush_color = 1;
-	float4 reveal_color = 1;
 
 	[branch]
 	if(push.texture_brush >= 0)
@@ -46,7 +45,7 @@ void main( uint3 DTid : SV_DispatchThreadID )
 		const float2 brush_uv_quad_y = QuadReadAcrossY(brush_uv);
 		const float2 brush_uv_dx = brush_uv - brush_uv_quad_x;
 		const float2 brush_uv_dy = brush_uv - brush_uv_quad_y;
-		brush_color = texture_brush.SampleGrad(sampler_linear_clamp, brush_uv, brush_uv_dx, brush_uv_dy);
+		brush_color *= texture_brush.SampleGrad(sampler_linear_clamp, brush_uv, brush_uv_dx, brush_uv_dy);
 	}
 
 	[branch]
@@ -58,22 +57,26 @@ void main( uint3 DTid : SV_DispatchThreadID )
 		const float2 reveal_uv_quad_y = QuadReadAcrossY(reveal_uv);
 		const float2 reveal_uv_dx = reveal_uv - reveal_uv_quad_x;
 		const float2 reveal_uv_dy = reveal_uv - reveal_uv_quad_y;
-		reveal_color = texture_reveal.SampleGrad(sampler_linear_clamp, reveal_uv, reveal_uv_dx, reveal_uv_dy);
+		brush_color *= texture_reveal.SampleGrad(sampler_linear_clamp, reveal_uv, reveal_uv_dx, reveal_uv_dy);
 	}
 
 	const float affection = push.xPaintBrushAmount * smoothstep(0, push.xPaintBrushSmoothness, 1 - dist / radius);
 	if (affection > 0 && dist < radius)
 	{
-		if (push.xPaintReveal)
-		{
-			brush_color *= reveal_color;
-		}
 		brush_color.a *= affection;
 		brush_color *= unpack_rgba(push.xPaintBrushColor);
 		float4 prevColor = texture_output[pixel];
 		float4 color = 0;
-		color.rgb = prevColor.rgb * (1 - brush_color.a) + brush_color.rgb * brush_color.a;
-		color.a = prevColor.a * (1 - brush_color.a) + brush_color.a;
+		if(push.xPaintRedirectAlpha)
+		{
+			color.rgb = prevColor.rgb;
+			color.a = prevColor.a * (1 - brush_color.a) + brush_color.r * brush_color.a;
+		}
+		else
+		{
+			color.rgb = prevColor.rgb * (1 - brush_color.a) + brush_color.rgb * brush_color.a;
+			color.a = prevColor.a * (1 - brush_color.a) + brush_color.a;
+		}
 		texture_output[pixel] = color;
 	}
 }

WickedEngine/wiRenderer.cpp

@@ -3021,7 +3021,6 @@ void ProcessDeferredTextureRequests(CommandList cmd)
 		for (auto& params : painttextures)
 		{
 			// overwrites some params!
-			params.push.xPaintReveal = params.revealTex.IsValid() ? 1 : 0;
 			if (params.brushTex.IsValid())
 			{
 				params.push.texture_brush = device->GetDescriptorIndex(&params.brushTex, SubresourceType::SRV);

WickedEngine/wiVersion.cpp

@@ -9,7 +9,7 @@ namespace wi::version
 	// minor features, major updates, breaking compatibility changes
 	const int minor = 71;
 	// minor bug fixes, alterations, refactors, updates
-	const int revision = 430;
+	const int revision = 431;
 
 	const std::string version_string = std::to_string(major) + "." + std::to_string(minor) + "." + std::to_string(revision);