Pass rect and matrix by value in geometry functions.

Several things irk me about passing values as const pointers:

* They can be NULL, which is not a valid value.
* They require explicit temporary variables for storage.
* They don't compose easily in a legible manner, requiring
  weird pointer passing semantics where the variable being assigned
  is hidden as an argument in the innermost function call.
* We can't change the value through the pointer, requiring yet more
  local variables to hold copies of the input value.

In the device interface where we pass a matrix to a function, we often
find ourselves making a local copy of the matrix so we can concatenate
other transforms to it. This copying is a lot of unnecessary busywork
that I hope to eventually avoid by laying the groundwork with this
commit.

This is a rather large API change, so I apologize for the inconvenience,
but I hope the end result and gain in legibility will be worth the pain.

1 files changed, 26 insertions, 27 deletions

diff --git a/platform/x11/pdfapp.c b/platform/x11/pdfapp.c
index 17af3d0f..20f4cc46 100644
--- a/platform/x11/pdfapp.c
+++ b/platform/x11/pdfapp.c
@@ -148,8 +148,7 @@ void pdfapp_setresolution(pdfapp_t *app, int res)
 
 void pdfapp_invert(pdfapp_t *app, const fz_rect *rect)
 {
-	fz_irect b;
-	fz_invert_pixmap_rect(app->ctx, app->image, fz_round_rect(&b, rect));
+	fz_invert_pixmap_rect(app->ctx, app->image, fz_round_rect(*rect));
 }
 
 void pdfapp_reloadfile(pdfapp_t *app)
@@ -262,7 +261,7 @@ static int make_fake_doc(pdfapp_t *app)
 		/* Create enough copies of our blank(ish) page so that the
 		 * page number is preserved if and when a subsequent load
 		 * works. */
-		page_obj = pdf_add_page(ctx, pdf, &mediabox, 0, NULL, contents);
+		page_obj = pdf_add_page(ctx, pdf, mediabox, 0, NULL, contents);
 		for (i = 0; i < app->pagecount; i++)
 			pdf_insert_page(ctx, pdf, -1, page_obj);
 	}
@@ -606,7 +605,7 @@ int pdfapp_preclose(pdfapp_t *app)
 
 static void pdfapp_viewctm(fz_matrix *mat, pdfapp_t *app)
 {
-	fz_pre_rotate(fz_scale(mat, app->resolution/72.0f, app->resolution/72.0f), app->rotate);
+	*mat = fz_pre_rotate(fz_scale(app->resolution/72.0f, app->resolution/72.0f), app->rotate);
 }
 
 static void pdfapp_panview(pdfapp_t *app, int newx, int newy)
@@ -671,8 +670,7 @@ static void pdfapp_loadpage(pdfapp_t *app, int no_cache)
 	fz_try(app->ctx)
 	{
 		app->page = fz_load_page(app->ctx, app->doc, app->pageno - 1);
-
-		fz_bound_page(app->ctx, app->page, &app->page_bbox);
+		app->page_bbox = fz_bound_page(app->ctx, app->page);
 	}
 	fz_catch(app->ctx)
 	{
@@ -687,7 +685,7 @@ static void pdfapp_loadpage(pdfapp_t *app, int no_cache)
 	{
 		fz_annot *annot;
 		/* Create display lists */
-		app->page_list = fz_new_display_list(app->ctx, NULL);
+		app->page_list = fz_new_display_list(app->ctx, fz_infinite_rect);
 		mdev = fz_new_list_device(app->ctx, app->page_list);
 		if (no_cache)
 			fz_enable_device_hints(app->ctx, mdev, FZ_NO_CACHE);
@@ -696,7 +694,7 @@ static void pdfapp_loadpage(pdfapp_t *app, int no_cache)
 		fz_close_device(app->ctx, mdev);
 		fz_drop_device(app->ctx, mdev);
 		mdev = NULL;
-		app->annotations_list = fz_new_display_list(app->ctx, NULL);
+		app->annotations_list = fz_new_display_list(app->ctx, fz_infinite_rect);
 		mdev = fz_new_list_device(app->ctx, app->annotations_list);
 		for (annot = fz_first_annot(app->ctx, app->page); annot; annot = fz_next_annot(app->ctx, annot))
 			fz_run_annot(app->ctx, annot, mdev, &fz_identity, &cookie);
@@ -757,7 +755,7 @@ static void pdfapp_recreate_annotationslist(pdfapp_t *app)
 	{
 		fz_annot *annot;
 		/* Create display list */
-		app->annotations_list = fz_new_display_list(app->ctx, NULL);
+		app->annotations_list = fz_new_display_list(app->ctx, fz_infinite_rect);
 		mdev = fz_new_list_device(app->ctx, app->annotations_list);
 		for (annot = fz_first_annot(app->ctx, app->page); annot; annot = fz_next_annot(app->ctx, annot))
 			fz_run_annot(app->ctx, annot, mdev, &fz_identity, &cookie);
@@ -813,9 +811,10 @@ static void pdfapp_updatepage(pdfapp_t *app)
 			fz_annot *annot = (fz_annot*)pannot;
 			fz_rect bounds;
 			fz_irect ibounds;
-			fz_transform_rect(fz_bound_annot(app->ctx, annot, &bounds), &ctm);
-			fz_rect_from_irect(&bounds, fz_round_rect(&ibounds, &bounds));
-			fz_clear_pixmap_rect_with_value(app->ctx, app->image, 255, &ibounds);
+			bounds = fz_transform_rect(fz_bound_annot(app->ctx, annot), ctm);
+			ibounds = fz_round_rect(bounds);
+			bounds = fz_rect_from_irect(ibounds);
+			fz_clear_pixmap_rect_with_value(app->ctx, app->image, 255, ibounds);
 			idev = fz_new_draw_device_with_bbox(app->ctx, NULL, app->image, &ibounds);
 			fz_try(app->ctx)
 			{
@@ -878,7 +877,8 @@ static void pdfapp_showpage(pdfapp_t *app, int loadpage, int drawpage, int repai
 		app->hit_count = 0;
 
 		/* Extract text */
-		app->page_text = fz_new_stext_page(app->ctx, fz_bound_page(app->ctx, app->page, &mediabox));
+		mediabox = fz_bound_page(app->ctx, app->page);
+		app->page_text = fz_new_stext_page(app->ctx, mediabox);
 
 		if (app->page_list || app->annotations_list)
 		{
@@ -914,9 +914,9 @@ static void pdfapp_showpage(pdfapp_t *app, int loadpage, int drawpage, int repai
 		wintitle(app, buf);
 
 		pdfapp_viewctm(&ctm, app);
-		bounds = app->page_bbox;
-		fz_round_rect(&ibounds, fz_transform_rect(&bounds, &ctm));
-		fz_rect_from_irect(&bounds, &ibounds);
+		bounds = fz_transform_rect(app->page_bbox, ctm);
+		ibounds = fz_round_rect(bounds);
+		bounds = fz_rect_from_irect(ibounds);
 
 		/* Draw */
 		fz_drop_pixmap(app->ctx, app->image);
@@ -931,7 +931,7 @@ static void pdfapp_showpage(pdfapp_t *app, int loadpage, int drawpage, int repai
 
 		fz_try(app->ctx)
 		{
-			app->image = fz_new_pixmap_with_bbox(app->ctx, colorspace, &ibounds, NULL, 1);
+			app->image = fz_new_pixmap_with_bbox(app->ctx, colorspace, ibounds, NULL, 1);
 			fz_clear_pixmap_with_value(app->ctx, app->image, 255);
 			if (app->page_list || app->annotations_list)
 			{
@@ -958,7 +958,7 @@ static void pdfapp_showpage(pdfapp_t *app, int loadpage, int drawpage, int repai
 			colorspace = fz_device_gray(app->ctx);
 		else
 			colorspace = app->colorspace;
-		app->image = fz_new_pixmap_with_bbox(app->ctx, colorspace, &ibounds, NULL, 1);
+		app->image = fz_new_pixmap_with_bbox(app->ctx, colorspace, ibounds, NULL, 1);
 		app->duration = 0;
 		fz_page_presentation(app->ctx, app->page, &app->transition, &app->duration);
 		if (app->duration == 0)
@@ -1051,7 +1051,8 @@ void pdfapp_inverthit(pdfapp_t *app)
 	for (i = 0; i < app->hit_count; i++)
 	{
 		bbox = fz_rect_from_quad(app->hit_bbox[i]);
-		pdfapp_invert(app, fz_transform_rect(&bbox, &ctm));
+		bbox = fz_transform_rect(bbox, ctm);
+		pdfapp_invert(app, &bbox);
 	}
 }
 
@@ -1624,14 +1625,14 @@ void pdfapp_onmouse(pdfapp_t *app, int x, int y, int btn, int modifiers, int sta
 	int processed = 0;
 
 	if (app->image)
-		fz_pixmap_bbox(app->ctx, app->image, &irect);
+		irect = fz_pixmap_bbox(app->ctx, app->image);
 	p.x = x - app->panx + irect.x0;
 	p.y = y - app->pany + irect.y0;
 
 	pdfapp_viewctm(&ctm, app);
-	fz_invert_matrix(&ctm, &ctm);
+	ctm = fz_invert_matrix(ctm);
 
-	fz_transform_point(&p, &ctm);
+	p = fz_transform_point(p, ctm);
 
 	if (btn == 1 && (state == 1 || state == -1))
 	{
@@ -1767,8 +1768,7 @@ void pdfapp_onmouse(pdfapp_t *app, int x, int y, int btn, int modifiers, int sta
 		fz_annot *annot;
 		for (annot = fz_first_annot(app->ctx, app->page); annot; annot = fz_next_annot(app->ctx, annot))
 		{
-			fz_rect rect;
-			fz_bound_annot(app->ctx, annot, &rect);
+			fz_rect rect = fz_bound_annot(app->ctx, annot);
 			if (x >= rect.x0 && x < rect.x1)
 				if (y >= rect.y0 && y < rect.y1)
 					break;
@@ -1921,9 +1921,8 @@ void pdfapp_oncopy(pdfapp_t *app, unsigned short *ucsbuf, int ucslen)
 	fz_rect sel;
 
 	pdfapp_viewctm(&ctm, app);
-	fz_invert_matrix(&ctm, &ctm);
-	sel = app->selr;
-	fz_transform_rect(&sel, &ctm);
+	ctm = fz_invert_matrix(ctm);
+	sel = fz_transform_rect(app->selr, ctm);
 
 	p = 0;
 	need_newline = 0;