Canvas.h

00001 /* NeatGUI Library
00002  * Copyright (c) 2013 Neil Thiessen
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 
00017 #ifndef CANVAS_H
00018 #define CANVAS_H
00019 
00020 #include "mbed.h"
00021 #include "Image.h"
00022 #include "Font.h"
00023 
00024 /** Canvas abstract class.
00025  *  Used as a base class for objects that provide 2D drawing capabilities.
00026  */
00027 class Canvas
00028 {
00029 public:
00030     /** Create a Canvas object with the specified width and height
00031      *
00032      * @param w The canvas width.
00033      * @param h The canvas height.
00034      */
00035     Canvas(int w, int h);
00036 
00037     /** Draw a single pixel at the specified coordinates
00038     *
00039     * @param x The X coordinate.
00040     * @param y The Y coordinate.
00041     * @param c The color of the pixel as a 32-bit ARGB value.
00042     */
00043     virtual void drawPixel(int x, int y, unsigned int c) = 0;
00044 
00045     /** Fill the entire canvas with the specified color using a filled rectangle
00046      *
00047      * @param c The color to fill with as a 32-bit ARGB value (black by default).
00048      */
00049     virtual void clear(unsigned int c = 0xFF000000);
00050 
00051     /** Draw a line between the specified coordinates using Bresenham's line algorithm
00052      *
00053      * @param x0 The starting X coordinate.
00054      * @param y0 The starting Y coordinate.
00055      * @param x1 The ending X coordinate.
00056      * @param y1 The ending Y coordinate.
00057      * @param c The color of the line as a 32-bit ARGB value.
00058      */
00059     virtual void drawLine(int x0, int y0, int x1, int y1, unsigned int c);
00060 
00061     /** Draw a fast horizontal line of the specified width, at the specified coordinates
00062      *
00063      * @param x The starting X coordinate.
00064      * @param y The starting Y coordinate.
00065      * @param w The width of the line.
00066      * @param c The color of the line as a 32-bit ARGB value.
00067      */
00068     virtual void drawHLine(int x, int y, int w, unsigned int c);
00069 
00070     /** Draw a fast vertical line of the specified height, at the specified coordinates
00071      *
00072      * @param x The starting X coordinate.
00073      * @param y The starting Y coordinate.
00074      * @param h The height of the line.
00075      * @param c The color of the line as a 32-bit ARGB value.
00076      */
00077     virtual void drawVLine(int x, int y, int h, unsigned int c);
00078 
00079     /** Draw an unfilled rectangle of the specified width and height, at the specified coordinates using fast lines
00080      *
00081      * @param x The starting X coordinate.
00082      * @param y The starting Y coordinate.
00083      * @param w The width of the rectangle.
00084      * @param h The height of the rectangle.
00085      * @param c The color of the rectangle as a 32-bit ARGB value.
00086      */
00087     virtual void drawRect(int x, int y, int w, int h, unsigned int c);
00088 
00089     /** Draw a filled rectangle of the specified width and height, at the specified coordinates using fast lines
00090      *
00091      * @param x The starting X coordinate.
00092      * @param y The starting Y coordinate.
00093      * @param w The width of the rectangle.
00094      * @param h The height of the rectangle.
00095      * @param c The color of the rectangle as a 32-bit ARGB value.
00096      */
00097     virtual void fillRect(int x, int y, int w, int h, unsigned int c);
00098 
00099     /** Draw an unfilled triangle with the specified vertices using lines
00100      *
00101      * @param x0 The first vertex X coordinate.
00102      * @param y0 The first vertex Y coordinate.
00103      * @param x1 The second vertex X coordinate.
00104      * @param y1 The second vertex Y coordinate.
00105      * @param x2 The third vertex X coordinate.
00106      * @param y2 The third vertex Y coordinate.
00107      * @param c The color of the triangle as a 32-bit ARGB value.
00108      */
00109     void drawTriangle(int x0, int y0, int x1, int y1, int x2, int y2, unsigned int c);
00110 
00111     /** Draw a filled triangle with the specified vertices using Adafruit's algorithm
00112      *
00113      * @param x0 The first vertex X coordinate.
00114      * @param y0 The first vertex Y coordinate.
00115      * @param x1 The second vertex X coordinate.
00116      * @param y1 The second vertex Y coordinate.
00117      * @param x2 The third vertex X coordinate.
00118      * @param y2 The third vertex Y coordinate.
00119      * @param c The color of the triangle as a 32-bit ARGB value.
00120      */
00121     void fillTriangle(int x0, int y0, int x1, int y1, int x2, int y2, unsigned int c);
00122 
00123     /** Draw an unfilled circle of the specified radius, at the specified coordinates using the midpoint circle algorithm
00124      *
00125      * @param x The center X coordinate.
00126      * @param y The center Y coordinate.
00127      * @param r The radius of the circle.
00128      * @param c The color of the circle as a 32-bit ARGB value.
00129      */
00130     void drawCircle(int x, int y, int r, unsigned int c);
00131 
00132     /** Draw a filled circle of the specified radius, at the specified coordinates using Adafruit's modified midpoint circle algorithm
00133      *
00134      * @param x The center X coordinate.
00135      * @param y The center Y coordinate.
00136      * @param r The radius of the circle.
00137      * @param c The color of the circle as a 32-bit ARGB value.
00138      */
00139     void fillCircle(int x, int y, int r, unsigned int c);
00140 
00141     /** Draw an unfilled rounded rectangle of the specified width, height, and corner radius, at the specified coordinates using Adafruit's algorithm
00142      *
00143      * @param x The starting X coordinate.
00144      * @param y The starting Y coordinate.
00145      * @param w The width of the rectangle.
00146      * @param h The height of the rectangle.
00147      * @param r The radius of the corners.
00148      * @param c The color of the rectangle as a 32-bit ARGB value.
00149      */
00150     void drawRoundRect(int x, int y, int w, int h, int r, unsigned int c);
00151 
00152     /** Draw a filled rounded rectangle of the specified width, height, and corner radius, at the specified coordinates using Adafruit's algorithm
00153      *
00154      * @param x The starting X coordinate.
00155      * @param y The starting Y coordinate.
00156      * @param w The width of the rectangle.
00157      * @param h The height of the rectangle.
00158      * @param r The radius of the corners.
00159      * @param c The color of the rectangle as a 32-bit ARGB value.
00160      */
00161     void fillRoundRect(int x, int y, int w, int h, int r, unsigned int c);
00162 
00163     /** Draw an Image object at the specified coordinates
00164      *
00165      * @param img Pointer to the image to draw.
00166      * @param x The starting X coordinate.
00167      * @param y The starting Y coordinate.
00168      */
00169     void drawImage(Image* img, int x, int y);
00170 
00171     /** Draw a character at the specified coordinates without wrapping
00172      *
00173      * @param c The character to draw.
00174      * @param fnt Pointer to the font to draw with.
00175      * @param x The starting X coordinate.
00176      * @param y The starting Y coordinate.
00177      *
00178      * @returns The width of the drawn character.
00179      */
00180     int drawChar(char c, Font* fnt, int x, int y);
00181 
00182     /** Draw a string at the specified coordinates without wrapping
00183      *
00184      * @param str Pointer to the string to draw.
00185      * @param fnt Pointer to the font to draw with.
00186      * @param x The starting X coordinate.
00187      * @param y The starting Y coordinate.
00188      */
00189     void drawString(const char* str, Font* fnt, int x, int y);
00190 
00191     /** Draw a string within the specified rectangle with wrapping
00192      *
00193      * @param str Pointer to the string to draw.
00194      * @param fnt Pointer to the font to draw with.
00195      * @param x The starting X coordinate.
00196      * @param y The starting Y coordinate.
00197      * @param w The width of the bounding rectangle.
00198      * @param h The height of the bounding rectangle.
00199      */
00200     void drawString(const char* str, Font* fnt, int x, int y, int w, int h);
00201 
00202     /** Get the width of the canvas
00203      *
00204      * @returns The width of the canvas.
00205      */
00206     int width();
00207 
00208     /** Get the height of the canvas
00209      *
00210      * @returns The height of the canvas.
00211      */
00212     int height();
00213 
00214 protected:
00215     //The canvas width/height
00216     int m_Width, m_Height;
00217 
00218     //Drawing helper functions
00219     void drawCircleHelper(int x, int y, int r, unsigned int corner, unsigned int color);
00220     void fillCircleHelper(int x, int y, int r, unsigned int corner, int delta, unsigned int color);
00221 };
00222 
00223 #endif