add:graphics:dpi scaling support (#813)

This commit adds calculating a scaling factor out of the virtual_dpi assumed when the layout was created, and the real_dpi value of the hardware. It is activated if "virtual_dpi" tag is set into the "graphics" tag on navit.xml.
Currently only qt5 graphics implment returning the hardware dpi. But this can be simulated and overwritten by setting "real_dpi" tag to "graphics" tag on navit.xm on all available graphics.l

1 files changed, 99 insertions, 82 deletions

diff --git a/navit/graphics.h b/navit/graphics.h
index befeb8e2b..eec44ae14 100644
--- a/navit/graphics.h
+++ b/navit/graphics.h
@@ -24,6 +24,7 @@
 
 #ifndef NAVIT_GRAPHICS_H
 #define NAVIT_GRAPHICS_H
+#include "coord.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -42,7 +43,7 @@ struct mapset;
 
 /* This enum must be synchronized with the constants in NavitGraphics.java. */
 enum draw_mode_num {
-	draw_mode_begin, draw_mode_end
+    draw_mode_begin, draw_mode_end
 };
 
 struct graphics_priv;
@@ -54,14 +55,14 @@ struct graphics_gc_methods;
 struct graphics_image_methods;
 
 enum graphics_image_type {
-	graphics_image_type_unknown=0,
+    graphics_image_type_unknown=0,
 };
 
 struct graphics_image_buffer {
-	char magic[8]; /* buffer:\0 */
-	enum graphics_image_type type;
-	void *start;
-	int len;
+    char magic[8]; /* buffer:\0 */
+    enum graphics_image_type type;
+    void *start;
+    int len;
 };
 
 struct graphics_keyboard_priv;
@@ -70,20 +71,20 @@ struct graphics_keyboard_priv;
  * Describes an instance of the native on-screen keyboard or other input method.
  */
 struct graphics_keyboard {
-	int w;										/**< The width of the area obscured by the keyboard (-1 for full width) */
-	int h;										/**< The height of the area obscured by the keyboard (-1 for full height) */
-	/* TODO mode is currently a copy of the respective value in the internal GUI and uses the same values.
-	 * This may need to be changed to something with globally available enum, possibly with revised values.
-	 * The Android implementation (the first to support a native on-screen keyboard) does not use this field
-	 * due to limitations of the platform. */
-	int mode;									/**< Mode flags for the keyboard */
-	char *lang;									/**< The preferred language for text input, may be {@code NULL}. */
-	void *gui_priv;								/**< Private data determined by the GUI. The GUI may store
+    int w;										/**< The width of the area obscured by the keyboard (-1 for full width) */
+    int h;										/**< The height of the area obscured by the keyboard (-1 for full height) */
+    /* TODO mode is currently a copy of the respective value in the internal GUI and uses the same values.
+     * This may need to be changed to something with globally available enum, possibly with revised values.
+     * The Android implementation (the first to support a native on-screen keyboard) does not use this field
+     * due to limitations of the platform. */
+    int mode;									/**< Mode flags for the keyboard */
+    char *lang;									/**< The preferred language for text input, may be {@code NULL}. */
+    void *gui_priv;								/**< Private data determined by the GUI. The GUI may store
 												 *   a pointer to a data structure of its choice here. It is
 												 *   the responsibility of the GUI to free the data structure
 												 *   when it is no longer needed. The graphics plugin should
 												 *   not access this member. */
-	struct graphics_keyboard_priv *gra_priv;	/**< Private data determined by the graphics plugin. The
+    struct graphics_keyboard_priv *gra_priv;	/**< Private data determined by the graphics plugin. The
 												 *   graphics plugin is responsible for its management. If it
 												 *   uses this member, it must free the associated data in
 												 *   its {@code hide_native_keyboard} method. */
@@ -108,67 +109,75 @@ struct graphics_keyboard {
  * to be visible as long as Navit is in the foreground.
  */
 struct padding {
-	int left;
-	int top;
-	int right;
-	int bottom;
+    int left;
+    int top;
+    int right;
+    int bottom;
 };
 
 struct graphics_methods {
-	void (*graphics_destroy)(struct graphics_priv *gr);
-	void (*draw_mode)(struct graphics_priv *gr, enum draw_mode_num mode);
-	void (*draw_lines)(struct graphics_priv *gr, struct graphics_gc_priv *gc, struct point *p, int count);
-	void (*draw_polygon)(struct graphics_priv *gr, struct graphics_gc_priv *gc, struct point *p, int count);
-	void (*draw_rectangle)(struct graphics_priv *gr, struct graphics_gc_priv *gc, struct point *p, int w, int h);
-	void (*draw_circle)(struct graphics_priv *gr, struct graphics_gc_priv *gc, struct point *p, int r);
-	void (*draw_text)(struct graphics_priv *gr, struct graphics_gc_priv *fg, struct graphics_gc_priv *bg, struct graphics_font_priv *font, char *text, struct point *p, int dx, int dy);
-	void (*draw_image)(struct graphics_priv *gr, struct graphics_gc_priv *fg, struct point *p, struct graphics_image_priv *img);
-	void (*draw_image_warp)(struct graphics_priv *gr, struct graphics_gc_priv *fg, struct point *p, int count, struct graphics_image_priv *img);
-	void (*draw_drag)(struct graphics_priv *gr, struct point *p);
-	struct graphics_font_priv *(*font_new)(struct graphics_priv *gr, struct graphics_font_methods *meth, char *font,  int size, int flags);
-	struct graphics_gc_priv *(*gc_new)(struct graphics_priv *gr, struct graphics_gc_methods *meth);
-	void (*background_gc)(struct graphics_priv *gr, struct graphics_gc_priv *gc);
-	struct graphics_priv *(*overlay_new)(struct graphics_priv *gr, struct graphics_methods *meth, struct point *p, int w, int h, int wraparound);
-	/** @brief Load an image from a file.
-	 *
-	 * @param gr graphics object
-	 * @param meth output parameter for graphics methods object
-	 * @param path file name/path of image to load
-	 * @param w In: width to scale image to, or IMAGE_W_H_UNSET for original width.
-	 * Out: Actual width of returned image.
-	 * @param h heigth; see w
-	 * @param hot output parameter for image hotspot
-	 * @param rotate angle to rotate the image, in 90 degree steps (not supported by all plugins).
-	 * @return pointer to allocated image, to be freed by image_free()
-	 * @see image_free()
-	 */
-	struct graphics_image_priv *(*image_new)(struct graphics_priv *gr, struct graphics_image_methods *meth, char *path, int *w, int *h, struct point *hot, int rotation);
-	void *(*get_data)(struct graphics_priv *gr, const char *type);
-	void (*image_free)(struct graphics_priv *gr, struct graphics_image_priv *priv);
-	void (*get_text_bbox)(struct graphics_priv *gr, struct graphics_font_priv *font, char *text, int dx, int dy, struct point *ret, int estimate);
-	void (*overlay_disable)(struct graphics_priv *gr, int disable);
-	void (*overlay_resize)(struct graphics_priv *gr, struct point *p, int w, int h, int wraparound);
-	int (*set_attr)(struct graphics_priv *gr, struct attr *attr);
-	int (*show_native_keyboard)(struct graphics_keyboard *kbd);
-	void (*hide_native_keyboard)(struct graphics_keyboard *kbd);
+    void (*graphics_destroy)(struct graphics_priv *gr);
+    void (*draw_mode)(struct graphics_priv *gr, enum draw_mode_num mode);
+    void (*draw_lines)(struct graphics_priv *gr, struct graphics_gc_priv *gc, struct point *p, int count);
+    void (*draw_polygon)(struct graphics_priv *gr, struct graphics_gc_priv *gc, struct point *p, int count);
+    void (*draw_rectangle)(struct graphics_priv *gr, struct graphics_gc_priv *gc, struct point *p, int w, int h);
+    void (*draw_circle)(struct graphics_priv *gr, struct graphics_gc_priv *gc, struct point *p, int r);
+    void (*draw_text)(struct graphics_priv *gr, struct graphics_gc_priv *fg, struct graphics_gc_priv *bg,
+                      struct graphics_font_priv *font, char *text, struct point *p, int dx, int dy);
+    void (*draw_image)(struct graphics_priv *gr, struct graphics_gc_priv *fg, struct point *p,
+                       struct graphics_image_priv *img);
+    void (*draw_image_warp)(struct graphics_priv *gr, struct graphics_gc_priv *fg, struct point *p, int count,
+                            struct graphics_image_priv *img);
+    void (*draw_drag)(struct graphics_priv *gr, struct point *p);
+    struct graphics_font_priv *(*font_new)(struct graphics_priv *gr, struct graphics_font_methods *meth, char *font,
+                                           int size, int flags);
+    struct graphics_gc_priv *(*gc_new)(struct graphics_priv *gr, struct graphics_gc_methods *meth);
+    void (*background_gc)(struct graphics_priv *gr, struct graphics_gc_priv *gc);
+    struct graphics_priv *(*overlay_new)(struct graphics_priv *gr, struct graphics_methods *meth, struct point *p, int w,
+                                         int h, int wraparound);
+    /** @brief Load an image from a file.
+     *
+     * @param gr graphics object
+     * @param meth output parameter for graphics methods object
+     * @param path file name/path of image to load
+     * @param w In: width to scale image to, or IMAGE_W_H_UNSET for original width.
+     * Out: Actual width of returned image.
+     * @param h heigth; see w
+     * @param hot output parameter for image hotspot
+     * @param rotate angle to rotate the image, in 90 degree steps (not supported by all plugins).
+     * @return pointer to allocated image, to be freed by image_free()
+     * @see image_free()
+     */
+    struct graphics_image_priv *(*image_new)(struct graphics_priv *gr, struct graphics_image_methods *meth, char *path,
+            int *w, int *h, struct point *hot, int rotation);
+    void *(*get_data)(struct graphics_priv *gr, const char *type);
+    void (*image_free)(struct graphics_priv *gr, struct graphics_image_priv *priv);
+    void (*get_text_bbox)(struct graphics_priv *gr, struct graphics_font_priv *font, char *text, int dx, int dy,
+                          struct point *ret, int estimate);
+    void (*overlay_disable)(struct graphics_priv *gr, int disable);
+    void (*overlay_resize)(struct graphics_priv *gr, struct point *p, int w, int h, int wraparound);
+    int (*set_attr)(struct graphics_priv *gr, struct attr *attr);
+    int (*show_native_keyboard)(struct graphics_keyboard *kbd);
+    void (*hide_native_keyboard)(struct graphics_keyboard *kbd);
+    navit_float (*get_dpi)(struct graphics_priv * gr);
 };
 
 
 struct graphics_font_methods {
-	void (*font_destroy)(struct graphics_font_priv *font);
+    void (*font_destroy)(struct graphics_font_priv *font);
 };
 
 struct graphics_font {
-	struct graphics_font_priv *priv;
-	struct graphics_font_methods meth;
+    struct graphics_font_priv *priv;
+    struct graphics_font_methods meth;
 };
 
 struct graphics_gc_methods {
-	void (*gc_destroy)(struct graphics_gc_priv *gc);
-	void (*gc_set_linewidth)(struct graphics_gc_priv *gc, int width);
-	void (*gc_set_dashes)(struct graphics_gc_priv *gc, int width, int offset, unsigned char dash_list[], int n);
-	void (*gc_set_foreground)(struct graphics_gc_priv *gc, struct color *c);
-	void (*gc_set_background)(struct graphics_gc_priv *gc, struct color *c);
+    void (*gc_destroy)(struct graphics_gc_priv *gc);
+    void (*gc_set_linewidth)(struct graphics_gc_priv *gc, int width);
+    void (*gc_set_dashes)(struct graphics_gc_priv *gc, int width, int offset, unsigned char dash_list[], int n);
+    void (*gc_set_foreground)(struct graphics_gc_priv *gc, struct color *c);
+    void (*gc_set_background)(struct graphics_gc_priv *gc, struct color *c);
 };
 
 /**
@@ -177,26 +186,26 @@ struct graphics_gc_methods {
  * linewidth and drawing color.
  */
 struct graphics_gc {
-	struct graphics_gc_priv *priv;
-	struct graphics_gc_methods meth;
-	struct graphics *gra;
+    struct graphics_gc_priv *priv;
+    struct graphics_gc_methods meth;
+    struct graphics *gra;
 };
 
 struct graphics_image_methods {
-	void (*image_destroy)(struct graphics_image_priv *img);
+    void (*image_destroy)(struct graphics_image_priv *img);
 };
 
 struct graphics_image {
-	struct graphics_image_priv *priv;
-	struct graphics_image_methods meth;
-	int width;
-	int height;
-	struct point hot;
+    struct graphics_image_priv *priv;
+    struct graphics_image_methods meth;
+    int width;
+    int height;
+    struct point hot;
 };
 
 struct graphics_data_image {
-	void *data;
-	int size;
+    void *data;
+    int size;
 };
 
 /* prototypes */
@@ -250,9 +259,12 @@ void graphics_draw_mode(struct graphics *this_, enum draw_mode_num mode);
 void graphics_draw_lines(struct graphics *this_, struct graphics_gc *gc, struct point *p, int count);
 void graphics_draw_circle(struct graphics *this_, struct graphics_gc *gc, struct point *p, int r);
 void graphics_draw_rectangle(struct graphics *this_, struct graphics_gc *gc, struct point *p, int w, int h);
-void graphics_draw_rectangle_rounded(struct graphics *this_, struct graphics_gc *gc, struct point *plu, int w, int h, int r, int fill);
-void graphics_draw_text(struct graphics *this_, struct graphics_gc *gc1, struct graphics_gc *gc2, struct graphics_font *font, char *text, struct point *p, int dx, int dy);
-void graphics_get_text_bbox(struct graphics *this_, struct graphics_font *font, char *text, int dx, int dy, struct point *ret, int estimate);
+void graphics_draw_rectangle_rounded(struct graphics *this_, struct graphics_gc *gc, struct point *plu, int w, int h,
+                                     int r, int fill);
+void graphics_draw_text(struct graphics *this_, struct graphics_gc *gc1, struct graphics_gc *gc2,
+                        struct graphics_font *font, char *text, struct point *p, int dx, int dy);
+void graphics_get_text_bbox(struct graphics *this_, struct graphics_font *font, char *text, int dx, int dy,
+                            struct point *ret, int estimate);
 void graphics_overlay_disable(struct graphics *this_, int disable);
 int  graphics_is_disabled(struct graphics *this_);
 void graphics_draw_image(struct graphics *this_, struct graphics_gc *gc, struct point *p, struct graphics_image *img);
@@ -261,8 +273,10 @@ void graphics_background_gc(struct graphics *this_, struct graphics_gc *gc);
 void graphics_draw_text_std(struct graphics *this_, int text_size, char *text, struct point *p);
 char *graphics_icon_path(const char *icon);
 void graphics_draw_itemgra(struct graphics *gra, struct itemgra *itm, struct transformation *t, char *label);
-void graphics_displaylist_draw(struct graphics *gra, struct displaylist *displaylist, struct transformation *trans, struct layout *l, int flags);
-void graphics_draw(struct graphics *gra, struct displaylist *displaylist, struct mapset *mapset, struct transformation *trans, struct layout *l, int async, struct callback *cb, int flags);
+void graphics_displaylist_draw(struct graphics *gra, struct displaylist *displaylist, struct transformation *trans,
+                               struct layout *l, int flags);
+void graphics_draw(struct graphics *gra, struct displaylist *displaylist, struct mapset *mapset,
+                   struct transformation *trans, struct layout *l, int async, struct callback *cb, int flags);
 int graphics_draw_cancel(struct graphics *gra, struct displaylist *displaylist);
 struct displaylist_handle *graphics_displaylist_open(struct displaylist *displaylist);
 struct displayitem *graphics_displaylist_next(struct displaylist_handle *dlh);
@@ -276,14 +290,17 @@ int graphics_displayitem_get_coord_count(struct displayitem *di);
 char *graphics_displayitem_get_label(struct displayitem *di);
 int graphics_displayitem_get_displayed(struct displayitem *di);
 int graphics_displayitem_get_z_order(struct displayitem *di);
-int graphics_displayitem_within_dist(struct displaylist *displaylist, struct displayitem *di, struct point *p, int dist);
+int graphics_displayitem_within_dist(struct displaylist *displaylist, struct displayitem *di, struct point *p,
+                                     int dist);
 void graphics_add_selection(struct graphics *gra, struct item *item, enum item_type type, struct displaylist *dl);
 void graphics_remove_selection(struct graphics *gra, struct item *item, enum item_type type, struct displaylist *dl);
 void graphics_clear_selection(struct graphics *gra, struct displaylist *dl);
 int graphics_show_native_keyboard (struct graphics *this_, struct graphics_keyboard *kbd);
 int graphics_hide_native_keyboard (struct graphics *this_, struct graphics_keyboard *kbd);
 void graphics_draw_polygon_clipped(struct graphics *gra, struct graphics_gc *gc, struct point *pin, int count_in);
-void graphics_draw_polyline_clipped(struct graphics *gra, struct graphics_gc *gc, struct point *pa, int count, int *width, int poly);
+void graphics_draw_polyline_clipped(struct graphics *gra, struct graphics_gc *gc, struct point *pa, int count,
+                                    int *width, int poly);
+navit_float graphics_get_dpi(struct graphics *gra);
 
 /* end of prototypes */
 #ifdef __cplusplus