diff --git a/include/constants.h b/include/constants.h
index 798b537..826ecc6 100644
--- a/include/constants.h
+++ b/include/constants.h
@@ -36,30 +36,31 @@ const int YEND = 950;
 
 // application constants
 
-const uint16_t LOGO_X = 80;
-const uint16_t LOGO_Y = 4;
-const uint16_t LOGO_C = WHITE;
+constexpr unsigned CANVAS_X = 4;
+constexpr unsigned CANVAS_Y = 30;
 
+constexpr unsigned CANVAS_W = 312;
+constexpr unsigned CANVAS_H = 312;
 
-const uint16_t CANVAS_W = 312;
-const uint16_t CANVAS_H = 312;
+constexpr unsigned CANVAS_BUFFER_W = 32;
+constexpr unsigned CANVAS_BUFFER_H = 32;
 
-const uint16_t CANVAS_X = 4;
-const uint16_t CANVAS_Y = 30;
+constexpr unsigned CANVAS_BUFFER_MAX_SEGMENTS = 18;
+constexpr unsigned CLIENT_BUFFER_MAX_SEGMENTS = 105;
 
 
-const uint16_t COLOR_SELECTOR_X = 40;
-const uint16_t COLOR_SELECTOR_Y = CANVAS_Y + CANVAS_H + 30;
+constexpr unsigned COLOR_SELECTOR_X = 40;
+constexpr unsigned COLOR_SELECTOR_Y = CANVAS_Y + CANVAS_H + 30;
 
-const uint16_t COLOR_SELECTOR_HPAD = 35;
-const uint16_t COLOR_SELECTOR_VPAD = 35;
+// const uint16_t COLOR_SELECTOR_HPAD = 35;
+// const uint16_t COLOR_SELECTOR_VPAD = 35;
 
-const uint16_t PAINT_RADIUS = 12;
+// const uint16_t PAINT_RADIUS = 12;
 
+constexpr unsigned THICKNESS_SELECTOR_X = 160;
+constexpr unsigned THICKNESS_SELECTOR_Y = COLOR_SELECTOR_Y;
 
-const uint16_t THICKNESS_SELECTOR_X = 160;
-const uint16_t THICKNESS_SELECTOR_Y = COLOR_SELECTOR_Y;
-const uint16_t THICKNESS_SELECTOR_PAD = 35;
+// const uint16_t THICKNESS_SELECTOR_PAD = 35;
 
 
 const uint16_t SAVE_X = 144;
@@ -106,10 +107,5 @@ const uint16_t SLOT_MENU_Y = COLOR_SELECTOR_Y - 8;
 const uint16_t SLOT_MENU_W = SAVE_W * 3;
 const uint16_t SLOT_MENU_H = SAVE_H * 4;
 
-constexpr unsigned CANVAS_BUFFER_W = 32;
-constexpr unsigned CANVAS_BUFFER_H = 32;
-
-constexpr unsigned CANVAS_BUFFER_MAX_SEGMENTS = 18;
-constexpr unsigned CLIENT_BUFFER_MAX_SEGMENTS = 105;
 
 #endif
\ No newline at end of file
diff --git a/include/widgets/button.h b/include/widgets/button.h
index 1e35b22..650f2d3 100644
--- a/include/widgets/button.h
+++ b/include/widgets/button.h
@@ -1,19 +1,17 @@
 #ifndef __WIDGETS_BUTTON_H__
 #define __WIDGETS_BUTTON_H__
 
-#include "Arduino.h"
-#include "Adafruit_GFX.h"
-#include "MCUFRIEND_kbv.h"
+#include "widget.h"
 
-class Button {
+class Button : Widget {
 
     MCUFRIEND_kbv *tft;
 
-    uint16_t x;
-    uint16_t y;
+    unsigned x;
+    unsigned y;
 
-    uint16_t w;
-    uint16_t h;
+    unsigned w;
+    unsigned h;
 
     uint16_t color;
 
@@ -21,10 +19,15 @@ class Button {
 
 public:
 
-    Button(uint16_t x, uint16_t y, uint16_t w, uint16_t h, uint16_t color, char *msg, MCUFRIEND_kbv *tft);
+    Button(unsigned x, unsigned y, unsigned w, unsigned h, uint16_t color, char *msg, MCUFRIEND_kbv *tft);
 
-    void    draw() const;
-    bool    update(uint16_t touchX, uint16_t touchY);
+    void    draw() const override;
+    void    clear() const override;
+
+    bool    update(unsigned touchX, unsigned touchY) override;
+
+    unsigned height() const override;
+    unsigned width() const override;
 
 private:
 
diff --git a/include/widgets/buttonGrid.h b/include/widgets/buttonGrid.h
index 361f42d..4974014 100644
--- a/include/widgets/buttonGrid.h
+++ b/include/widgets/buttonGrid.h
@@ -1,52 +1,51 @@
 #ifndef __WIDGETS_BUTTON_GRID_H__
 #define __WIDGETS_BUTTON_GRID_H__
 
-#include "Arduino.h"
-#include "Adafruit_GFX.h"
-#include "MCUFRIEND_kbv.h"
-
 #include "constants.h"
+#include "widget.h"
 
-class ButtonGrid {
-
-    const char *msg = "SLOT"" ";
+class ButtonGrid : Widget {
 
-    const uint16_t SLOT_CLOSE_X = 2;
-    const uint16_t SLOT_CLOSE_Y = 2;
-    const uint16_t SLOT_CLOSE_W = 13;
+    static constexpr char *msg = "SLOT"" ";
 
-    const uint16_t SLOT_MENU_C = GRAY;
+    static constexpr unsigned CLOSE_X = 2;
+    static constexpr unsigned CLOSE_Y = 2;
+    static constexpr unsigned CLOSE_W = 13;
 
-    const uint16_t SLOT_OPTION_X = 23;
-    const uint16_t SLOT_OPTION_Y = 8;
+    static constexpr unsigned HPAD = 23;
+    static constexpr unsigned VPAD = 8;
 
-    const uint16_t SLOT_OPTION_W = SAVE_W;
-    const uint16_t SLOT_OPTION_H = SAVE_H;
-    const uint16_t SLOT_OPTION_C = WHITE;
+    static constexpr uint16_t BUTTON_C = WHITE;
 
     MCUFRIEND_kbv *tft;
 
-    uint16_t x;
-    uint16_t y;
+    unsigned x;
+    unsigned y;
 
-    uint16_t w;
-    uint16_t h;
+    unsigned w;
+    unsigned h;
 
-    uint16_t cc;
-    uint16_t rc;
+    unsigned cc;
+    unsigned rc;
 
-    uint16_t slot;
+    unsigned button_w;
+    unsigned button_h;
+
+    unsigned slot;
 
 public:
 
-    ButtonGrid(uint16_t x, uint16_t y, uint16_t w, uint16_t h, uint16_t c, uint16_t r, MCUFRIEND_kbv *tft);
+    ButtonGrid(unsigned x, unsigned y, unsigned w, unsigned h, unsigned cc, unsigned rc, unsigned button_w, unsigned button_h, MCUFRIEND_kbv *tft);
+
+    void    draw() const override;
+    void    clear() const override;
 
-    void    draw() const;
-    bool    update(uint16_t touchX, uint16_t touchY);
+    bool    update(unsigned touch_x, unsigned touch_y) override;
 
-    void    clear();
+    unsigned height() const override;
+    unsigned width() const override;
 
-    uint16_t getSlot() const;
+    unsigned getSlot() const;
 
 private:
 
diff --git a/include/widgets/canvas.h b/include/widgets/canvas.h
index 4318fef..698da42 100644
--- a/include/widgets/canvas.h
+++ b/include/widgets/canvas.h
@@ -1,34 +1,44 @@
 #ifndef __WIDGETS_CANVAS_H__
 #define __WIDGETS_CANVAS_H__
 
-#include "Arduino.h"
-#include "Adafruit_GFX.h"
-#include "MCUFRIEND_kbv.h"
+#include "widget.h"
 
-class Canvas {
+class Canvas : Widget {
 
     MCUFRIEND_kbv *tft;
 
-    uint16_t x;
-    uint16_t y;
+    unsigned x;
+    unsigned y;
 
-    uint16_t w;
-    uint16_t h;
+    unsigned w;
+    unsigned h;
+
+    unsigned thickness;
+    uint16_t color;
 
 public:
 
-    Canvas(uint16_t x, uint16_t y, uint16_t w, uint16_t h, MCUFRIEND_kbv *tft);
+    Canvas(unsigned x, unsigned y, unsigned w, unsigned h, MCUFRIEND_kbv *tft);
+
+    void    draw() const override;
+    void    clear() const override;
+
+    bool    update(unsigned touch_x, unsigned touch_y) override;
+
+    unsigned height() const override;
+    unsigned width() const override;
+
+    unsigned heightInternal() const;
+    unsigned widthInternal() const;
 
-    void    draw() const;
-    bool    update(uint16_t touchX, uint16_t touchY, uint16_t curThickness, uint16_t curColor);
+    void    setThickness(unsigned curThickness);
+    void    setColor(uint16_t curColor);
 
-    void    clear();
+    void    clearDrawing();
 
-    uint16_t readPixel(uint16_t r, uint16_t c) const;
-    void    writePixel(uint16_t r, uint16_t c, uint16_t color);
+    uint16_t readPixel(unsigned r, unsigned c) const;
+    void    writePixel(unsigned r, unsigned c, uint16_t color);
 
-    uint16_t height() const;
-    uint16_t width() const;
 
 private:
 
diff --git a/include/widgets/colorSelector.h b/include/widgets/colorSelector.h
index 9c685cb..956a23b 100644
--- a/include/widgets/colorSelector.h
+++ b/include/widgets/colorSelector.h
@@ -1,38 +1,43 @@
 #ifndef __WIDGETS_COLOR_SELECTOR_H__
 #define __WIDGETS_COLOR_SELECTOR_H__
 
-#include "Arduino.h"
-#include "Adafruit_GFX.h"
-#include "MCUFRIEND_kbv.h"
+#include "widget.h"
 
 #include "constants.h"
 
-class ColorSelector {
+class ColorSelector : Widget {
 
-    constexpr static uint16_t colors[3][3] {
+    constexpr static uint16_t COLORS[3][3] {
         {RED, GREEN, BLUE},
         {CYAN, MAGENTA, YELLOW},
         {WHITE, GRAY, BLACK}
     };
 
-    MCUFRIEND_kbv *tft;
+    constexpr static unsigned HPAD = 35;
+    constexpr static unsigned VPAD = 35;
+    constexpr static unsigned PAINT_RADIUS = 12;
 
-    uint16_t x;
-    uint16_t y;
+    constexpr static unsigned HEIGHT = (PAINT_RADIUS/2) + (3*HPAD);
+    constexpr static unsigned WIDTH = (PAINT_RADIUS/2) + (3*VPAD);
 
-    uint16_t hpad;
-    uint16_t vpad;
+    MCUFRIEND_kbv *tft;
 
-    uint16_t paintRadius;
+    unsigned x;
+    unsigned y;
 
-    uint16_t curColor = WHITE;
+    uint16_t curColor;
 
 public:
 
-    ColorSelector(uint16_t x, uint16_t y, uint16_t hpad, uint16_t vpad, uint16_t paintRadius, MCUFRIEND_kbv *tft);
+    ColorSelector(unsigned x, unsigned y, MCUFRIEND_kbv *tft);
+
+    void    draw() const override;
+    void    clear() const override;
+
+    bool    update(unsigned touch_x, unsigned touch_y) override;
 
-    void    draw() const;
-    bool    update(uint16_t touchX, uint16_t touchY);
+    unsigned height() const;
+    unsigned width() const;
 
     uint16_t getColor() const;
 
diff --git a/include/widgets/thicknessSelector.h b/include/widgets/thicknessSelector.h
index 795b098..de966a9 100644
--- a/include/widgets/thicknessSelector.h
+++ b/include/widgets/thicknessSelector.h
@@ -1,32 +1,38 @@
 #ifndef __WIDGETS_THICKNESS_SELECTOR_H__
 #define __WIDGETS_THICKNESS_SELECTOR_H__
 
-#include "Arduino.h"
-#include "Adafruit_GFX.h"
-#include "MCUFRIEND_kbv.h"
+#include "widget.h"
 
-class ThicknessSelector {
+class ThicknessSelector : Widget {
 
-    const uint16_t radii[4] = {3, 5, 7, 9};
+    static constexpr unsigned RADII[4] = {3, 5, 7, 9};
+    static constexpr unsigned PAD = 35;
 
-    MCUFRIEND_kbv *tft;
+    static constexpr unsigned HEIGHT = 0;
+    static constexpr unsigned WIDTH = 0;
 
-    uint16_t x;
-    uint16_t y;
+    MCUFRIEND_kbv *tft;
 
-    uint16_t pad;
+    unsigned x;
+    unsigned y;
 
     uint16_t color;
-    uint16_t curSelected;
+    unsigned curSelected;
 
 public:
 
-    ThicknessSelector(uint16_t x, uint16_t y, uint16_t pad, MCUFRIEND_kbv *tft);
+    ThicknessSelector(unsigned x, unsigned y, MCUFRIEND_kbv *tft);
 
     void    setColor(uint16_t clr);
 
-    void    draw() const;
-    bool    update(uint16_t touchX, uint16_t touchY);
+    void    draw() const override;
+    void    clear() const override;
+
+    bool    update(unsigned touch_x, unsigned touch_y) override;
+
+    unsigned height() const override;
+    unsigned width() const override;
+
     uint16_t getThickness() const;
 
 private:
diff --git a/src/canvasClient.cpp b/src/canvasClient.cpp
index 57bb41d..957d696 100644
--- a/src/canvasClient.cpp
+++ b/src/canvasClient.cpp
@@ -59,8 +59,8 @@ void CanvasClient::loadCanvas(uint8_t id, Compressor<CANVAS_BUFFER_MAX_SEGMENTS>
         return;
     }
 
-    uint16_t imageHeight = canvas->height() - 2;
-    uint16_t imageWidth = canvas->width() - 2;
+    uint16_t imageHeight = canvas->heightInternal();
+    uint16_t imageWidth = canvas->widthInternal();
 
     client.write("\x02", 1);
     client.write(&id, 1);
@@ -86,7 +86,7 @@ void CanvasClient::loadCanvas(uint8_t id, Compressor<CANVAS_BUFFER_MAX_SEGMENTS>
         }
 
         for (uint16_t j = 0; j < imageWidth; ++j) {
-            canvas->writePixel(row + 1, j + 1, rowbuf.color[j]);
+            canvas->writePixel(row, j, rowbuf.color[j]);
         }
 
         for (uint16_t j = 0; j < imageWidth; ++j) {
@@ -125,7 +125,7 @@ void CanvasClient::saveCanvas(uint8_t id, Compressor<CANVAS_BUFFER_MAX_SEGMENTS>
         }
         else {
             for (unsigned j = compressed[i].uncompress(rowbuf.code); j < imageWidth; ++j) {
-                rowbuf.code[j] = color2code(canvas->readPixel(i + 1, j + 1));
+                rowbuf.code[j] = color2code(canvas->readPixel(i, j));
             }
             compressable = compressor.compress(rowbuf.code, imageWidth);
         }
diff --git a/src/main.cpp b/src/main.cpp
index 46fa706..3b2f818 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -23,9 +23,9 @@
 MCUFRIEND_kbv tft;
 
 Canvas canvas(CANVAS_X, CANVAS_Y, CANVAS_W, CANVAS_H, &tft);
-ColorSelector colorSelector(COLOR_SELECTOR_X, COLOR_SELECTOR_Y, COLOR_SELECTOR_HPAD, COLOR_SELECTOR_VPAD, PAINT_RADIUS, &tft);
-ThicknessSelector thicknessSelector(THICKNESS_SELECTOR_X, THICKNESS_SELECTOR_Y, THICKNESS_SELECTOR_PAD, &tft);
-ButtonGrid slotSelector(SLOT_MENU_X, SLOT_MENU_Y, SLOT_MENU_W, SLOT_MENU_H, 2, 3, &tft);
+ColorSelector colorSelector(COLOR_SELECTOR_X, COLOR_SELECTOR_Y, &tft);
+ThicknessSelector thicknessSelector(THICKNESS_SELECTOR_X, THICKNESS_SELECTOR_Y, &tft);
+ButtonGrid slotSelector(SLOT_MENU_X, SLOT_MENU_Y, SLOT_MENU_W, SLOT_MENU_H, 2, 3, 72, 28, &tft);
 
 Button loadButton(LOAD_X, LOAD_Y, LOAD_W, LOAD_H, LOAD_C, "LOAD", &tft);
 Button saveButton(SAVE_X, SAVE_Y, SAVE_W, SAVE_H, SAVE_C, "SAVE", &tft);
@@ -36,7 +36,6 @@ CanvasClient client(&canvas);
 
 GFXcanvas1 canvasBuffer(CANVAS_BUFFER_W, CANVAS_BUFFER_H);
 
-// CompressedRow compressed[CANVAS_H - 2];
 Compressor<CANVAS_BUFFER_MAX_SEGMENTS> compressed[CANVAS_H - 2];
 uint8_t rawCode[CANVAS_W - 2] {};
 
@@ -78,7 +77,10 @@ void loop(void) {
         const uint16_t color = colorSelector.getColor();
         const uint8_t code = color2code(color);
 
-        if (canvas.update(x, y, thickness, color)) {
+        canvas.setThickness(thickness);
+        canvas.setColor(color);
+
+        if (canvas.update(x, y)) {
 
             const uint16_t canvasX = x - CANVAS_X - 1;
             const uint16_t canvasY = y - CANVAS_Y - 1;
@@ -163,7 +165,7 @@ void loop(void) {
     }
 
     if (clearButton.update(x, y)) {
-        canvas.clear();
+        canvas.clearDrawing();
         clearCompressedCanvas();
     }
 
diff --git a/src/widgets/button.cpp b/src/widgets/button.cpp
index a17e009..0962f81 100644
--- a/src/widgets/button.cpp
+++ b/src/widgets/button.cpp
@@ -2,7 +2,7 @@
 #include "constants.h"
 #include "helper.h"
 
-Button::Button(uint16_t x, uint16_t y, uint16_t w, uint16_t h, uint16_t color, char *msg, MCUFRIEND_kbv *tft)
+Button::Button(unsigned x, unsigned y, unsigned w, unsigned h, uint16_t color, char *msg, MCUFRIEND_kbv *tft)
     : x {x}
     , y {y}
     , w {w}
@@ -23,7 +23,12 @@ void Button::draw() const {
     tft->print(msg);
 }
 
-bool Button::update(uint16_t touchX, uint16_t touchY) {
+void Button::clear() const {
+
+    tft->fillRect(x, y, w, h, BLACK);
+}
+
+bool Button::update(unsigned touchX, unsigned touchY) {
 
     if (!inRange(touchX, x, x + w) || !inRange(touchY, y, y + h)) {
         return false;
@@ -31,3 +36,11 @@ bool Button::update(uint16_t touchX, uint16_t touchY) {
 
     return true;
 }
+
+unsigned Button::height() const {
+    return h;
+}
+
+unsigned Button::width() const {
+    return w;
+}
diff --git a/src/widgets/buttonGrid.cpp b/src/widgets/buttonGrid.cpp
index 364069b..b021dfa 100644
--- a/src/widgets/buttonGrid.cpp
+++ b/src/widgets/buttonGrid.cpp
@@ -2,84 +2,93 @@
 #include "constants.h"
 #include "helper.h"
 
-ButtonGrid::ButtonGrid(uint16_t x, uint16_t y, uint16_t w, uint16_t h, uint16_t c, uint16_t r, MCUFRIEND_kbv *tft)
+ButtonGrid::ButtonGrid(unsigned x, unsigned y, unsigned w, unsigned h, unsigned cc, unsigned rc, unsigned button_w, unsigned button_h, MCUFRIEND_kbv *tft)
     : x {x}
     , y {y}
     , w {w}
     , h {h}
-    , cc {c}
-    , rc {r}
+    , cc {cc}
+    , rc {rc}
+    , button_w {button_w}
+    , button_h {button_h}
     , tft {tft}
+    , slot {}
 {}
 
 void ButtonGrid::draw() const {
 
+    unsigned i, j;
+
     tft->fillRect(x, y, w, h, BLACK);
     tft->drawRect(x, y, w, h, GRAY);
 
-    tft->fillRoundRect(x + SLOT_CLOSE_X, y + SLOT_CLOSE_Y, SLOT_CLOSE_W, SLOT_CLOSE_W, SLOT_CLOSE_W / 2, RED);
+    tft->fillRoundRect(x + CLOSE_X, y + CLOSE_Y, CLOSE_W, CLOSE_W, CLOSE_W / 2, RED);
 
     tft->setTextColor(WHITE, BLACK);
     tft->setTextSize(2);
 
-    for (uint16_t r = 0; r < rc; ++r) {
-        for (uint16_t c = 0; c < cc; ++c) {
+    for (unsigned r = 0; r < rc; ++r) {
+
+        for (unsigned c = 0; c < cc; ++c) {
 
-            uint16_t i = x + SLOT_OPTION_X*(c + 1) + SLOT_OPTION_W*(c);
-            uint16_t j = y + SLOT_OPTION_Y*(r + 1) + SLOT_OPTION_H*(r);
+            j = y + VPAD + (button_h + VPAD)*r;
+            i = x + HPAD + (button_w + HPAD)*c;
 
-            tft->drawRect(
-                i,
-                j,
-                SLOT_OPTION_W,
-                SLOT_OPTION_H,
-                WHITE
-            );
+            tft->drawRect(i, j, button_w, button_h, WHITE);
 
             tft->setCursor(i, j);
 
             tft->print(msg);
             tft->print(1 + r + (c * rc));
+
+            // delay(2000);
         }
     }
 }
 
-bool ButtonGrid::update(uint16_t touchX, uint16_t touchY) {
+bool ButtonGrid::update(unsigned touch_x, unsigned touch_y) {
 
-    // close button pressed
-    if (inRange(touchX, x + SLOT_CLOSE_X, x + SLOT_CLOSE_X + SLOT_CLOSE_W) && inRange(touchY, y + SLOT_CLOSE_Y, y + SLOT_CLOSE_Y + SLOT_CLOSE_W)) { // close this menu
+    if (inRange(touch_x, x + CLOSE_X, x + CLOSE_X + CLOSE_W)
+        && inRange(touch_y, y + CLOSE_Y, y + CLOSE_Y + CLOSE_W)) { // close this menu
 
         slot = 0;
         return true;
     }
 
-    for (uint16_t r = 0; r < rc; ++r) {
-        for (uint16_t c = 0; c < cc; ++c) {
-
-            if (!inRange(
-                    touchX,
-                    x + SLOT_OPTION_X*(c + 1) + SLOT_OPTION_W*(c),
-                    x + SLOT_OPTION_X*(c + 1) + SLOT_OPTION_W*(c + 1)) ||
-                !inRange(
-                    touchY,
-                    y + SLOT_OPTION_Y*(r + 1) + SLOT_OPTION_H*(r),
-                    y + SLOT_OPTION_Y*(r + 1) + SLOT_OPTION_H*(r + 1))) {
-                continue;
-            }
+    for (unsigned r = 0; r < rc; ++r) {
+        for (unsigned c = 0; c < cc; ++c) {
+
+            if (inRange(
+                    touch_x,
+                    x + HPAD + (button_w + HPAD)*c,
+                    x + (button_w + HPAD)*(c + 1)) &&
+                inRange(
+                    touch_y,
+                    y + VPAD + (button_h + VPAD)*r,
+                    y + (button_h + VPAD)*(r + 1))) {
 
-            slot = 1 + r + (c * rc);
-            return true;
+                slot = 1 + r + (c * rc);
+                return true;
+            }
         }
     }
 
     return false;
 }
 
-void ButtonGrid::clear() {
+void ButtonGrid::clear() const {
 
     tft->fillRect(x, y, w, h, BLACK);
 }
 
-uint16_t ButtonGrid::getSlot() const {
+unsigned ButtonGrid::height() const {
+    return h;
+}
+
+unsigned ButtonGrid::width() const {
+    return w;
+}
+
+unsigned ButtonGrid::getSlot() const {
     return slot;
 }
diff --git a/src/widgets/canvas.cpp b/src/widgets/canvas.cpp
index 0cee463..0027a51 100644
--- a/src/widgets/canvas.cpp
+++ b/src/widgets/canvas.cpp
@@ -2,48 +2,70 @@
 #include "constants.h"
 #include "helper.h"
 
-Canvas::Canvas(uint16_t x, uint16_t y, uint16_t w, uint16_t h, MCUFRIEND_kbv *tft)
+Canvas::Canvas(unsigned x, unsigned y, unsigned w, unsigned h, MCUFRIEND_kbv *tft)
     : x {x}
     , y {y}
     , w {w}
     , h {h}
     , tft {tft}
+    , thickness {}
+    , color {}
 {}
 
 void Canvas::draw() const {
     tft->drawRect(x, y, w, h, WHITE);
 }
 
-bool Canvas::update(uint16_t touchX, uint16_t touchY, uint16_t curThickness, uint16_t curColor) {
+void Canvas::clear() const {
+    tft->fillRect(x, y, w, h, BLACK);
+}
+
+bool Canvas::update(unsigned touch_x, unsigned touch_y) {
 
-    if (inRange(touchX, x + curThickness + 2, x + w - curThickness - 2)
-        && inRange(touchY, y + curThickness + 2, y + h - curThickness - 2)) {
+    if (inRange(touch_x, x + thickness + 2, x + w - thickness - 2)
+        && inRange(touch_y, y + thickness + 2, y + h - thickness - 2)) {
 
-            tft->fillCircle(touchX, touchY, curThickness, curColor);
+            tft->fillCircle(touch_x, touch_y, thickness, color);
             return true;
     }
     return false;
 }
 
-void Canvas::clear() {
-    tft->fillRect(x + 1, y + 1, w - 2, h - 2, BLACK);
+unsigned Canvas::height() const {
+    return h;
 }
 
+unsigned Canvas::width() const {
+    return w;
+}
+
+unsigned Canvas::heightInternal() const {
+    return h - 2;
+}
 
-uint16_t Canvas::readPixel(uint16_t r, uint16_t c) const {
+unsigned Canvas::widthInternal() const {
+    return w - 2;
+}
 
-    return tft->readPixel(x + c, y + r);
+void Canvas::setThickness(unsigned curThickness) {
+    thickness = curThickness;
 }
 
-void Canvas::writePixel(uint16_t r, uint16_t c, uint16_t color) {
+void Canvas::setColor(uint16_t curColor) {
+    color = curColor;
+}
 
-    tft->writePixel(x + c, y + r, color);
+void Canvas::clearDrawing() {
+    tft->fillRect(x + 1, y + 1, w - 2, h - 2, BLACK);
 }
 
-uint16_t Canvas::height() const {
-    return h;
+
+uint16_t Canvas::readPixel(unsigned r, unsigned c) const {
+
+    return tft->readPixel(x + c + 1, y + r + 1);
 }
 
-uint16_t Canvas::width() const {
-    return w;
+void Canvas::writePixel(unsigned r, unsigned c, uint16_t color) {
+
+    tft->writePixel(x + c + 1, y + r + 1, color);
 }
diff --git a/src/widgets/colorSelector.cpp b/src/widgets/colorSelector.cpp
index 2578a21..619ada8 100644
--- a/src/widgets/colorSelector.cpp
+++ b/src/widgets/colorSelector.cpp
@@ -2,48 +2,53 @@
 #include "constants.h"
 #include "helper.h"
 
-ColorSelector::ColorSelector(uint16_t x, uint16_t y, uint16_t hpad, uint16_t vpad, uint16_t paintRadius, MCUFRIEND_kbv *tft)
+ColorSelector::ColorSelector(unsigned x, unsigned y, MCUFRIEND_kbv *tft)
     : x {x}
     , y {y}
-    , hpad {hpad}
-    , vpad {vpad}
-    , paintRadius {paintRadius}
     , tft {tft}
+    , curColor {WHITE}
 {}
 
 
 void ColorSelector::draw() const {
 
-    for (uint16_t r = 0; r < 3; ++r) {
+    unsigned i, j;
+    uint16_t color;
 
-        for (uint16_t c = 0; c < 3; ++c) {
+    for (unsigned r = 0; r < 3; ++r) {
 
-            uint16_t i = x + (c * hpad);
-            uint16_t j = y + (r * vpad);
-            uint16_t color = colors[r][c];
+        for (unsigned c = 0; c < 3; ++c) {
 
-            tft->fillCircle(i, j, paintRadius, color);
-            tft->drawCircle(i, j, paintRadius + 2, WHITE);
+            i = x + (c * HPAD);
+            j = y + (r * VPAD);
+            color = COLORS[r][c];
+
+            tft->fillCircle(i, j, PAINT_RADIUS, color);
+            tft->drawCircle(i, j, PAINT_RADIUS + 2, WHITE);
         }
     }
 }
 
-bool ColorSelector::update(uint16_t touchX, uint16_t touchY) {
+void ColorSelector::clear() const {
+    tft->fillRect(x, y, WIDTH, HEIGHT, BLACK);
+}
+
+bool ColorSelector::update(unsigned touch_x, unsigned touch_y) {
 
     uint32_t i, j, d;
 
-    for (uint16_t r = 0; r < 3; ++r) {
+    for (unsigned r = 0; r < 3; ++r) {
 
-        for (uint16_t c = 0; c < 3; ++c) {
+        for (unsigned c = 0; c < 3; ++c) {
 
-            i = x + (c * hpad);
-            j = y + (r * vpad);
+            i = x + (c * HPAD);
+            j = y + (r * VPAD);
 
-            d = distance(i, j, touchX, touchY);
+            d = distance(i, j, touch_x, touch_y);
 
             if (d <= PAINT_RADIUS) {
 
-                curColor = colors[r][c];
+                curColor = COLORS[r][c];
                 return true;
             }
         }
@@ -52,6 +57,14 @@ bool ColorSelector::update(uint16_t touchX, uint16_t touchY) {
     return false;
 }
 
+unsigned ColorSelector::height() const { //todo
+    return HEIGHT;
+}
+
+unsigned ColorSelector::width() const { //todo
+    return WIDTH;
+}
+
 uint16_t ColorSelector::getColor() const {
     return curColor;
 }
diff --git a/src/widgets/thicknessSelector.cpp b/src/widgets/thicknessSelector.cpp
index eda029a..c6aeb84 100644
--- a/src/widgets/thicknessSelector.cpp
+++ b/src/widgets/thicknessSelector.cpp
@@ -2,11 +2,10 @@
 #include "constants.h"
 #include "helper.h"
 
-ThicknessSelector::ThicknessSelector(uint16_t x, uint16_t y, uint16_t pad, MCUFRIEND_kbv *tft)
+ThicknessSelector::ThicknessSelector(unsigned x, unsigned y, MCUFRIEND_kbv *tft)
     : x {x}
     , y {y}
-    , pad {pad}
-    , curSelected {radii[0]}
+    , curSelected {RADII[0]}
     , tft {tft}
 {}
 
@@ -16,13 +15,13 @@ void ThicknessSelector::setColor(uint16_t clr) {
 
 void ThicknessSelector::draw() const {
 
-    uint16_t i, j, t;
+    unsigned i, j, t;
 
-    for (uint16_t c = 0; c < 4; ++c) {
+    for (unsigned c = 0; c < 4; ++c) {
 
-        i = x + (pad * c);
+        i = x + (PAD * c);
         j = y;
-        t = radii[c];
+        t = RADII[c];
 
         (color == BLACK)
         ? tft->fillCircle(i, j, t, TFT_DARKGREY)
@@ -34,17 +33,21 @@ void ThicknessSelector::draw() const {
     }
 }
 
-bool ThicknessSelector::update(uint16_t touchX, uint16_t touchY) {
+void ThicknessSelector::clear() const { //todo
 
-    uint32_t i, j, t, d;
+}
+
+bool ThicknessSelector::update(unsigned touch_x, unsigned touch_y) {
 
-    for (uint16_t c = 0; c < 4; ++c) {
+    unsigned i, j, t, d;
 
-        i = x + (pad * c);
+    for (unsigned c = 0; c < 4; ++c) {
+
+        i = x + (PAD * c);
         j = y;
-        t = radii[c];
+        t = RADII[c];
 
-        d = distance(i, j, touchX, touchY);
+        d = distance(i, j, touch_x, touch_y);
 
         // the pen is in this color if the distance between its centre
         // and the pen is less than the radius of the paint
@@ -59,6 +62,14 @@ bool ThicknessSelector::update(uint16_t touchX, uint16_t touchY) {
     return false;
 }
 
+unsigned ThicknessSelector::height() const {
+    return HEIGHT;
+}
+
+unsigned ThicknessSelector::width() const {
+    return WIDTH;
+}
+
 uint16_t ThicknessSelector::getThickness() const {
     return curSelected;
 }