text widget has a constant buffer and owns the string to draw now

(passing a const char * from a local stack context is not really a
good idea!)
added more efficiet draw method for characters in vga driver
protected desktop for now against too often redraws (boolean global
variable needs_redraw, this is later a soffisticated set-of-areas-to
-redraw algorithm)

4 files changed, 25 insertions, 6 deletions

diff --git a/src/gui/desktop.c b/src/gui/desktop.c
index 6592b52..ad4aad9 100644
--- a/src/gui/desktop.c
+++ b/src/gui/desktop.c
@@ -28,6 +28,7 @@ void desktop_init( desktop_t *desktop, const int w, const int h, const vga_color
 
 	desktop->mouse_x = w / 2;
 	desktop->mouse_y = h / 2;
+	desktop->needs_redrawing = true;
 
 	desktop->base.base.vtable = (widget_vtable_t *)&desktop_vtable;
 	desktop->base.vtable = (composite_widget_vtable_t *)&desktop_vtable;
@@ -38,6 +39,10 @@ void desktop_draw( void *obj, graphics_context_t *context )
 {
 	desktop_t *desktop = obj;
 
+	if( !desktop->needs_redrawing ) {
+		return;
+	}
+
 	vga_clear_screen( context, desktop->base.base.background_color );
 
 	composite_widget_draw( obj, context );
@@ -56,16 +61,26 @@ void desktop_draw( void *obj, graphics_context_t *context )
 			vga_set_pixel( context, desktop->mouse_x, desktop->mouse_y + i, VGA_COLOR_WHITE );
 		}
 	}
+
+	desktop->needs_redrawing = false;
 }
 
 void desktop_on_mouse_down( void *obj, const int x, const int y )
 {
+	desktop_t *desktop = obj;
+
 	composite_widget_on_mouse_down( obj, x, y );
+
+	desktop->needs_redrawing = true;
 }
 
 void desktop_on_mouse_up( void *obj, const int x, const int y )
 {
+	desktop_t *desktop = obj;
+
 	composite_widget_on_mouse_up( obj, x, y );
+
+	desktop->needs_redrawing = true;
 }
 
 void desktop_on_mouse_move( void *obj, const int old_x, const int old_y, const int x, const int y )
@@ -76,4 +91,6 @@ void desktop_on_mouse_move( void *obj, const int old_x, const int old_y, const i
 	desktop->mouse_y = y;
 
 	composite_widget_on_mouse_move( obj, old_x, old_y, x, y );
+
+	desktop->needs_redrawing = true;
 }
diff --git a/src/gui/desktop.h b/src/gui/desktop.h
index a8db094..a9d1946 100644
--- a/src/gui/desktop.h
+++ b/src/gui/desktop.h
@@ -5,6 +5,8 @@
 
 #define MAX_NOF_WIDGET_CHILDREN 100
 
+#include <stdbool.h>
+
 typedef struct {
 	composite_widget_vtable_t base;
 } desktop_vtable_t;
@@ -14,6 +16,7 @@ typedef struct {
 	desktop_vtable_t *vtable;
 	int mouse_x;
 	int mouse_y;
+	bool needs_redrawing;
 } desktop_t;
 
 void desktop_init( desktop_t *widget, const int w, const int h, const vga_color_t background_color );
diff --git a/src/gui/text_widget.c b/src/gui/text_widget.c
index eea2613..db237af 100644
--- a/src/gui/text_widget.c
+++ b/src/gui/text_widget.c
@@ -24,9 +24,7 @@ void text_widget_init( text_widget_t *widget, widget_t *parent, const int x, con
 
 	widget_init( &widget->base, parent, x, y, w, h, background_color );	
 
-	// TODO: const for now, caller has to preserve the text
-	// maybe with memory manager in place we can do this with a strdup
-	widget->s = s;
+	text_widget_set_text( widget, s );
 
 	widget->base.vtable = (widget_vtable_t *)&text_widget_vtable;
 	widget->vtable = &text_widget_vtable;
@@ -61,7 +59,6 @@ void text_widget_set_text( void *obj, const char *s )
 {
 	text_widget_t *widget = obj;
 
-	// TODO: see above
-	widget->s = s;
+	strlcpy( widget->s, s, TEXT_WIDGET_MAX_TEXT_SIZE );
 }
 
diff --git a/src/gui/text_widget.h b/src/gui/text_widget.h
index 4b00b4f..7e87a3c 100644
--- a/src/gui/text_widget.h
+++ b/src/gui/text_widget.h
@@ -3,6 +3,8 @@
 
 #include "widget.h"
 
+#define TEXT_WIDGET_MAX_TEXT_SIZE 100
+
 typedef struct {
 	widget_vtable_t base;
 	void (*set_text)( void *obj, const char *s );
@@ -11,7 +13,7 @@ typedef struct {
 typedef struct {
 	widget_t base;
 	text_widget_vtable_t *vtable;
-	const char *s;
+	char s[TEXT_WIDGET_MAX_TEXT_SIZE];
 } text_widget_t;
 
 void text_widget_init( text_widget_t *widget, widget_t *parent, const int x, const int y, const int w, const int h, const vga_color_t background_color, const char *s );