Rob Boss Painter

Features:

• Paint vertex colors on any mesh in your Unity scene.
• Paint textures directly on a mesh.
• Paint flowmaps using your brush direction.
• Color mask allows painting on individual color channels.
• Pen pressure support.
• Normal, Add, Subtract, and Multiply blend modes.

Open the tool by clicking Window > Rob Boss Painter in the menu bar.

Example textures from cc0textures.com

Includes height map based puddle and texture blending shaders.