Added pen pressure sensitivity (fix aseprite#710)

- Added support to detect eraser tip on Linux (aseprite#610)
- Related to aseprite#139
- Still needs works for gradients and better brush interpolations
  between stroke points
- Requested several times, e.g. https://community.aseprite.org/t/1077
  https://community.aseprite.org/t/1881, steam forum, etc.

.travis.yml

@@ -11,23 +11,23 @@ matrix:
       addons:
         apt:
           packages:
-            - libpixman-1-dev libfreetype6-dev libharfbuzz-dev libx11-dev libxcursor-dev ninja-build
+            - libpixman-1-dev libfreetype6-dev libharfbuzz-dev libx11-dev libxcursor-dev libxi-dev ninja-build
       env:
         - ENABLE_UI=OFF
         - XVFB=xvfb-run
     - os: linux
       addons:
         apt:
           packages:
-            - libpixman-1-dev libfreetype6-dev libharfbuzz-dev libx11-dev libxcursor-dev ninja-build
+            - libpixman-1-dev libfreetype6-dev libharfbuzz-dev libx11-dev libxcursor-dev libxi-dev ninja-build
       env:
         - ENABLE_SCRIPTING=OFF
         - XVFB=xvfb-run
     - os: linux
       addons:
         apt:
           packages:
-            - libpixman-1-dev libfreetype6-dev libharfbuzz-dev libx11-dev libxcursor-dev ninja-build
+            - libpixman-1-dev libfreetype6-dev libharfbuzz-dev libx11-dev libxcursor-dev libxi-dev ninja-build
       env:
         - ENABLE_SCRIPTING=OFF
         - ENABLE_UI=OFF
@@ -37,7 +37,7 @@ matrix:
       addons:
         apt:
           packages:
-            - libpixman-1-dev libfreetype6-dev libharfbuzz-dev libx11-dev libxcursor-dev ninja-build
+            - libpixman-1-dev libfreetype6-dev libharfbuzz-dev libx11-dev libxcursor-dev libxi-dev ninja-build
       env:
         - ENABLE_UI=ON
         - XVFB=xvfb-run
@@ -47,7 +47,7 @@ matrix:
           sources:
             - ubuntu-toolchain-r-test
           packages:
-            - g++-7 libpixman-1-dev libfreetype6-dev libharfbuzz-dev libx11-dev libxcursor-dev ninja-build
+            - g++-7 libpixman-1-dev libfreetype6-dev libharfbuzz-dev libx11-dev libxcursor-dev libxi-dev ninja-build
       env:
         - MATRIX_EVAL="CC=gcc-7 && CXX=g++-7"
         - ENABLE_UI=ON

INSTALL.md

@@ -72,11 +72,11 @@ versions might work).
 
 You will need the following dependencies on Ubuntu/Debian:
 
-    sudo apt-get install -y g++ cmake ninja-build libx11-dev libxcursor-dev libgl1-mesa-dev libfontconfig1-dev
+    sudo apt-get install -y g++ cmake ninja-build libx11-dev libxcursor-dev libxi-dev libgl1-mesa-dev libfontconfig1-dev
 
 On Fedora:
 
-    sudo dnf install -y gcc-c++ cmake ninja-build libX11-devel libXcursor-devel mesa-libGL-devel fontconfig-devel
+    sudo dnf install -y gcc-c++ cmake ninja-build libX11-devel libXcursor-devel libXi-devel mesa-libGL-devel fontconfig-devel
 
 # Compiling
 

data/extensions/aseprite-theme/theme.xml

@@ -418,6 +418,7 @@
         <part id="outline_vertical" x="192" y="224" w="13" h="15" />
         <part id="outline_empty_pixel" x="208" y="224" w="5" h="5" />
         <part id="outline_full_pixel" x="214" y="224" w="5" h="5" />
+        <part id="dynamics" x="176" y="144" w="16" h="16" />
     </parts>
     <styles>
         <style id="box" />

data/strings/en.ini

@@ -422,6 +422,7 @@ SetSameInk = Same Ink in All Tools
 ShowAutoGuides = Show Auto Guides
 ShowBrushPreview = Show Brush Preview
 ShowBrushes = Show Brushes
+ShowDynamics = Show Dynamics
 ShowExtras = Show Extras
 ShowGrid = Show Grid
 ShowLayerEdges = Show Layer Edges
@@ -520,6 +521,28 @@ duplicate = Duplicate:
 as = As:
 merged_layers = Duplicate merged layers only
 
+[dynamics]
+pressure = Pressure
+pressure_tooltip = Control parameters through the pen pressure sensor
+velocity = Velocity
+velocity_tooltip = Control parameters through the mouse velocity
+size = Size:
+size_tooltip = <<<END
+Change the brush size
+depending on the sensor value
+END
+angle = Angle:
+angle_tooltip = <<<END
+Change the brush angle
+depending on the sensor value
+END
+gradient = Gradient:
+gradient_tooltip = <<<END
+Gradient between foreground
+and background colors
+END
+max_point_value = Max Point Value:
+
 [export_file]
 title = Export File
 output_file = Output File:

data/widgets/dynamics.xml

@@ -0,0 +1,39 @@
+<!-- Aseprite -->
+<!-- Copyright (C) 2020  Igara Studio S.A. -->
+<gui>
+  <vbox id="dynamics">
+    <hbox>
+    <buttonset id="values" columns="3">
+      <item text="" />
+      <item text="@.pressure" tooltip="@.pressure_tooltip" tooltip_dir="bottom" />
+      <item text="@.velocity" tooltip="@.velocity_tooltip" tooltip_dir="bottom" />
+
+      <item text="@.size" tooltip="@.size_tooltip" tooltip_dir="right" />
+      <item text="" maxheight="1" />
+      <item text="" maxheight="1" />
+
+      <item text="@.angle" tooltip="@.angle_tooltip" tooltip_dir="right" />
+      <item text="" maxheight="1" />
+      <item text="" maxheight="1" />
+
+      <item text="@.gradient" tooltip="@.gradient_tooltip" tooltip_dir="right" />
+      <item text="" maxheight="1" />
+      <item text="" maxheight="1" />
+    </buttonset>
+    </hbox>
+
+    <separator id="separator" text="@.max_point_value" horizontal="true" />
+
+    <grid id="options" columns="2" childspacing="0" expansive="true">
+      <label id="max_size_label" text="@.size" style="mini_label" />
+      <slider id="max_size" value="64" min="1" max="64" cell_align="horizontal" />
+
+      <label id="max_angle_label" text="@.angle" style="mini_label"  />
+      <slider id="max_angle" value="0" min="-180" max="+180" cell_align="horizontal" />
+
+      <label id="gradient_label" text="@.gradient" style="mini_label"  />
+      <hbox id="gradient_placeholder" />
+    </grid>
+
+  </vbox>
+</gui>

src/app/CMakeLists.txt

@@ -319,6 +319,7 @@ if(ENABLE_UI)
     ui/dithering_selector.cpp
     ui/doc_view.cpp
     ui/drop_down_button.cpp
+    ui/dynamics_popup.cpp
     ui/editor/brush_preview.cpp
     ui/editor/drawing_state.cpp
     ui/editor/editor.cpp

src/app/script/app_object.cpp

@@ -328,7 +328,12 @@ int App_useTool(lua_State* L)
     while (lua_next(L, -2) != 0) {
       gfx::Point pt = convert_args_into_point(L, -1);
 
-      tools::Pointer pointer(pt, tools::Pointer::Button::Left);
+      tools::Pointer pointer(
+        pt,
+        // TODO configurable params
+        tools::Pointer::Button::Left,
+        tools::Pointer::Type::Unknown,
+        0.0f);
       if (first) {
         first = false;
         manager.prepareLoop(pointer);

src/app/tools/dynamics.h

@@ -0,0 +1,42 @@
+// Aseprite
+// Copyright (C) 2020  Igara Studio S.A.
+//
+// This program is distributed under the terms of
+// the End-User License Agreement for Aseprite.
+
+#ifndef APP_TOOLS_DYNAMICS_H_INCLUDED
+#define APP_TOOLS_DYNAMICS_H_INCLUDED
+#pragma once
+
+#include "render/dithering_algorithm.h"
+#include "render/dithering_matrix.h"
+
+namespace app {
+namespace tools {
+
+  enum class DynamicSensor {
+    Static,
+    Pressure,
+    Velocity,
+  };
+
+  struct DynamicsOptions {
+    DynamicSensor size = DynamicSensor::Static;
+    DynamicSensor angle = DynamicSensor::Static;
+    DynamicSensor gradient = DynamicSensor::Static;
+    int maxSize = 0;
+    int maxAngle = 0;
+    render::DitheringAlgorithm ditheringAlgorithm = render::DitheringAlgorithm::None;
+    render::DitheringMatrix ditheringMatrix;
+
+    bool isDynamic() const {
+      return (size != DynamicSensor::Static ||
+              angle != DynamicSensor::Static ||
+              gradient != DynamicSensor::Static);
+    }
+  };
+
+} // namespace tools
+} // namespace app
+
+#endif

src/app/tools/point_shapes.h

@@ -37,21 +37,26 @@ class PixelPointShape : public PointShape {
 };
 
 class BrushPointShape : public PointShape {
-  Brush* m_brush;
+  Brush* m_lastBrush;
   std::shared_ptr<CompressedImage> m_compressedImage;
   bool m_firstPoint;
 
 public:
 
   void preparePointShape(ToolLoop* loop) override {
-    m_brush = loop->getBrush();
-    m_compressedImage.reset(new CompressedImage(m_brush->image(),
-                                                m_brush->maskBitmap(),
-                                                false));
     m_firstPoint = true;
+    m_lastBrush = nullptr;
   }
 
   void transformPoint(ToolLoop* loop, int x, int y) override {
+    Brush* m_brush = loop->getBrush();
+    if (m_lastBrush != m_brush) {
+      m_lastBrush = m_brush;
+      m_compressedImage.reset(new CompressedImage(m_brush->image(),
+                                                  m_brush->maskBitmap(),
+                                                  false));
+    }
+
     x += m_brush->bounds().x;
     y += m_brush->bounds().y;
 
@@ -91,7 +96,7 @@ class BrushPointShape : public PointShape {
   }
 
   void getModifiedArea(ToolLoop* loop, int x, int y, Rect& area) override {
-    area = m_brush->bounds();
+    area = loop->getBrush()->bounds();
     area.x += x;
     area.y += y;
   }

src/app/tools/pointer.h

@@ -1,4 +1,5 @@
 // Aseprite
+// Copyright (C) 2020  Igara Studio S.A.
 // Copyright (C) 2016  David Capello
 //
 // This program is distributed under the terms of
@@ -9,6 +10,7 @@
 #pragma once
 
 #include "gfx/point.h"
+#include "ui/pointer_type.h"
 
 namespace app {
 namespace tools {
@@ -17,19 +19,33 @@ namespace tools {
 class Pointer {
 public:
   enum Button { None, Left, Middle, Right };
+  typedef ui::PointerType Type;
 
   Pointer()
-    : m_point(0, 0), m_button(None) { }
-
-  Pointer(const gfx::Point& point, Button button)
-    : m_point(point), m_button(button) { }
+    : m_point(0, 0)
+    , m_button(None)
+    , m_type(Type::Unknown)
+    , m_pressure(0.0f) { }
+
+  Pointer(const gfx::Point& point,
+          const Button button,
+          const Type type,
+          const float pressure)
+    : m_point(point)
+    , m_button(button)
+    , m_type(type)
+    , m_pressure(pressure) { }
 
   const gfx::Point& point() const { return m_point; }
   Button button() const { return m_button; }
+  Type type() const { return m_type; }
+  float pressure() const { return m_pressure; }
 
 private:
   gfx::Point m_point;
   Button m_button;
+  Type m_type;
+  float m_pressure;
 };
 
 } // namespace tools

src/app/tools/tool_loop.h

@@ -9,8 +9,10 @@
 #define APP_TOOLS_TOOL_LOOP_H_INCLUDED
 #pragma once
 
+#include "app/tools/dynamics.h"
 #include "app/tools/tool_loop_modifiers.h"
 #include "app/tools/trace_policy.h"
+#include "doc/brush.h"
 #include "doc/color.h"
 #include "doc/frame.h"
 #include "filters/tiled_mode.h"
@@ -23,7 +25,6 @@ namespace gfx {
 }
 
 namespace doc {
-  class Brush;
   class Image;
   class Layer;
   class Mask;
@@ -72,6 +73,7 @@ namespace app {
 
       // Returns the brush which will be used with the tool
       virtual Brush* getBrush() = 0;
+      virtual void setBrush(const BrushRef& newBrush) = 0;
 
       // Returns the document to which belongs the sprite.
       virtual Doc* getDocument() = 0;
@@ -235,6 +237,9 @@ namespace app {
       virtual render::DitheringAlgorithmBase* getDitheringAlgorithm() = 0;
       virtual render::GradientType getGradientType() = 0;
 
+      // For freehand algorithms with dynamics
+      virtual tools::DynamicsOptions getDynamics() = 0;
+
       // Called when the user release the mouse on SliceInk
       virtual void onSliceRect(const gfx::Rect& bounds) = 0;
     };