Diff: RA8875.h

Revision:

96:40b74dd3695b

Parent:

90:d113d71ae4f0

Child:

98:ecebed9b80b2

--- a/RA8875.h	Tue Jul 07 17:05:59 2015 +0000
+++ b/RA8875.h	Sat Nov 28 15:39:44 2015 +0000
@@ -104,6 +104,7 @@
 //namespace SW_graphics
 //{
 
+class FPointerDummy;    // used by the callback methods.
 
 /// This is a graphics library for the Raio RA8875 Display Controller chip
 /// attached to a 4-wire SPI interface.
@@ -219,6 +220,49 @@
         TP_Auto,               ///< Auto touch detection mode
         TP_Manual,             ///< Manual touch detection mode
     } tpmode_t;
+
+    /// printscreen callback commands
+    typedef enum
+    {
+        OPEN,       ///< command to open the file. cast uint32_t * to the buffer to get the total size to be written.
+        WRITE,      ///< command to write some data, buffer points to the data and the size is in bytes.
+        CLOSE,      ///< command to close the file
+    } filecmd_t;
+
+    /// print screen callback
+    ///
+    /// The special form of the print screen will pass one blob at a time 
+    /// to the callback. There are basic command declaring that the stream
+    /// can be opened, a block written, and the stream closed. There is
+    /// also a command to communicate the total size being delivered.
+    ///
+    /// @code
+    /// lcd.PrintScreen(x,y,w,h,callback);
+    /// ... 
+    /// void callback(filecmd_t cmd, uint8_t * buffer, uint16_t size) {
+    ///     switch(cmd) {
+    ///         case OPEN:
+    ///             pc.printf("About to write %u bytes\r\n", *(uint32_t *)buffer);
+    ///             fh = fopen("file.bmp", "w+b");
+    ///             break;
+    ///         case WRITE:
+    ///             fwrite(buffer, size, fh);
+    ///             break;
+    ///         case CLOSE:
+    ///             fclose(fh);
+    ///             break;
+    ///         default:
+    ///             pc.printf("Unexpected callback %d\r\n", cmd);
+    ///             break;
+    ///     }
+    /// }
+    /// @endcode
+    ///
+    /// @param cmd is the command to execute. @see filecmd_t.
+    /// @param buffer is a pointer to the buffer being passed.
+    /// @param size is the number of bytes in the buffer.
+    ///
+    typedef RetCode_t (* PrintCallback_T)(filecmd_t cmd, uint8_t * buffer, uint16_t size);
     
     /// Constructor for a display based on the RAiO RA8875 
     /// display controller.
@@ -1812,6 +1856,51 @@
     ///
     RetCode_t PrintScreen(loc_t x, loc_t y, dim_t w, dim_t h, const char *Name_BMP);
     
+    /// This method captures the specified area as a 24-bit bitmap file
+    /// and delivers it to the previously attached callback.
+    ///
+    /// Even though this is a 16-bit display, the stored image is in
+    /// 24-bit format.
+    ///
+    /// This method will interrogate the current display setting and
+    /// create a bitmap based on those settings. For instance, if 
+    /// only layer 1 is visible, then the bitmap is only layer 1. However,
+    /// if there is some other operation in effect (transparent mode), it
+    /// will return the blended image.
+    ///
+    /// @param[in] x is the left edge of the region to capture
+    /// @param[in] y is the top edge of the region to capture
+    /// @param[in] w is the width of the region to capture
+    /// @param[in] h is the height of the region to capture.
+    /// @return success or error code.
+    ///
+    RetCode_t PrintScreen(loc_t x, loc_t y, dim_t w, dim_t h);
+    
+    /// PrintScreen callback registration.
+    ///
+    /// This method attaches a simple c-compatible callback of type PrintCallback_T.
+    /// Then, the PrintScreen(x,y,w,h) method is called. Each chunk of data in the
+    /// BMP file to be created is passed to this callback.
+    /// 
+    /// @param callback is the callback function.
+    ///
+    void AttachPrintHandler(PrintCallback_T callback) { c_callback = callback; }
+
+    /// PrintScreen callback registration.
+    ///
+    /// This method attaches a c++ class method as a callback of type PrintCallback_T.
+    /// Then, the PrintScreen(x,y,w,h) method is called. Each chunk of data in the
+    /// BMP file to be created is passed to this callback.
+    /// 
+    /// @param object is the class hosting the callback function.
+    /// @param callback is the callback function.
+    ///
+    template <class T>
+    void AttachPrintHandler(T *object, RetCode_t (T::*member)(void)) { 
+        obj_callback    = (FPointerDummy *)item; 
+        method_callback = (uint32_t (FPointerDummy::*)(uint32_t))method;
+    }
+
     /// This method captures the specified area as a 24-bit bitmap file,
     /// including the option of layer selection.
     ///
@@ -2003,8 +2092,29 @@
     void RegisterPerformance(method_e method);
     Timer performance;
     #endif
+    
+    RetCode_t _printCallback(RA8875::filecmd_t cmd, uint8_t * buffer, uint16_t size);
+    
+    FILE * _printFH;             ///< PrintScreen file handle
+    
+    RetCode_t privateCallback(filecmd_t cmd, uint8_t * buffer, uint16_t size) {
+        if (c_callback != NULL) {
+            return (*c_callback)(cmd, buffer, size);
+        }
+        else {
+            if (obj_callback != NULL && method_callback != NULL) {
+                return (obj_callback->*method_callback)(cmd, buffer, size);
+            }
+        }
+        return noerror;
+    }
+    
+    RetCode_t (* c_callback)(filecmd_t cmd, uint8_t * buffer, uint16_t size);
+    FPointerDummy  *obj_callback;
+    RetCode_t (FPointerDummy::*method_callback)(filecmd_t cmd, uint8_t * buffer, uint16_t size);
 };
 
+
 //}     // namespace
 
 //using namespace SW_graphics;