psimage: fix -B+t>title> issue

src/gmt_init.c

@@ -4866,6 +4866,12 @@ GMT_LOCAL int gmtinit_parse5_B_frame_setting (struct GMT_CTRL *GMT, char *in) {
 	/* Now parse the frame choices, if any */
 	error += gmtinit_decode5_wesnz (GMT, text, true);
 
+	/* Issue #5635: Only set frame.draw = true when a modifier that actually requires a drawn frame outline
+	 * is given (+w pen, +b 3D box, +w wall). Plain +t<title>, +s<subtitle>, +g<fill> must NOT cause an
+	 * unwanted frame outline; title/subtitle render via map_annotate path, fill via plotcanvas. */
+	if (GMT->current.map.frame.draw_wall || (GMT->current.map.frame.draw_box & (GMT_3D_BOX | GMT_3D_WALL)))
+		GMT->current.map.frame.draw = true;
+
 	return (error);
 }
 

src/gmt_plot.c

@@ -470,6 +470,8 @@ GMT_LOCAL unsigned char * gmtplot_latex_eps (struct GMT_CTRL *GMT, struct GMT_FO
 
 /*	GMT_LINEAR PROJECTION MAP BOUNDARY	*/
 
+GMT_LOCAL double gmtplot_place_latex_eps(struct GMT_CTRL *GMT, double x, double y, struct GMT_FONT *F, const char *string);
+
 GMT_LOCAL void gmtplot_linear_map_boundary (struct GMT_CTRL *GMT, struct PSL_CTRL *PSL, double w, double e, double s, double n) {
 	unsigned int cap = PSL->internal.line_cap;
 	double x_length, y_length;
@@ -524,6 +526,41 @@ GMT_LOCAL void gmtplot_linear_map_boundary (struct GMT_CTRL *GMT, struct PSL_CTR
 
 	PSL_comment (PSL, "Placing plot title\n");
 
+	if (GMT->current.proj.three_D) {
+		/* Issue #5635: place the title parallel to the rotated top edge of the map rect.
+		 * Project the two top corners (XLO,YHI) and (XHI,YHI) at the current z-level to
+		 * paper space, take their midpoint, offset perpendicularly outward by the title
+		 * offset, and rotate the text to match the edge slope. */
+		int form, old_plane = GMT->current.proj.z_project.plane;
+		double old_level = GMT->current.proj.z_project.level;
+		double xTL, yTL, xTR, yTR, xm, ym, ex, ey, nx, ny, nlen, ang, off;
+		double z_for_proj = gmt_z_to_zz(GMT, GMT->current.proj.z_level);
+		gmt_xyz_to_xy(GMT, GMT->current.proj.rect[XLO], GMT->current.proj.rect[YHI], z_for_proj, &xTL, &yTL);
+		gmt_xyz_to_xy(GMT, GMT->current.proj.rect[XHI], GMT->current.proj.rect[YHI], z_for_proj, &xTR, &yTR);
+		ex = xTR - xTL;
+		ey = yTR - yTL;
+		ang = atan2d(ey, ex);
+		/* Outward (CCW perpendicular) unit normal */
+		nx = -ey;
+		ny =  ex;
+		nlen = hypot(nx, ny);
+		if (nlen > 0.0) { nx /= nlen; ny /= nlen; }
+		off = GMT->current.setting.map_title_offset;
+		xm = 0.5 * (xTL + xTR) + off * nx;
+		ym = 0.5 * (yTL + yTR) + off * ny;
+		gmt_plane_perspective(GMT, -1, 0.0);
+		if (gmt_text_is_latex(GMT, GMT->current.map.frame.header)) {
+			(void)gmtplot_place_latex_eps(GMT, xm, ym, &GMT->current.setting.font_title, GMT->current.map.frame.header);
+		}
+		else {
+			form = gmt_setfont(GMT, &GMT->current.setting.font_title);
+			PSL_plottext(PSL, xm, ym, GMT->current.setting.font_title.size, GMT->current.map.frame.header, ang, -PSL_BC, form);
+		}
+		GMT->current.map.frame.plotted_header = true;
+		gmt_plane_perspective(GMT, old_plane, old_level);
+		return;
+	}
+
 	y_length += GMT->current.setting.map_graph_shift;  /* Extra shift (set in gmt_xy_axis) for map title when we have a centered y-axis with vector */
 
 	if (!GMT->current.map.frame.draw || GMT->current.map.frame.side[N_SIDE] <= GMT_AXIS_DRAW || GMT->current.setting.map_frame_type == GMT_IS_INSIDE)

src/psimage.c

@@ -607,17 +607,19 @@ EXTERN_MSC int GMT_psimage (void *V_API, int mode, void *args) {
 
 	/* The following is needed to have psimage work correctly in perspective */
 
+	bool fake_J_only = false;	/* Issue #5635: track whether we took the no-R fake-J branch so we skip the redundant re-setup */
 	gmt_set_basemap_orders (GMT, GMT_BASEMAP_FRAME_AFTER, GMT_BASEMAP_GRID_AFTER, GMT_BASEMAP_ANNOT_AFTER);
 	gmt_M_memset (wesn, 4, double);
 	if (!(GMT->common.R.active[RSET] && GMT->common.J.active)) {	/* When no projection specified, use fake linear projection */
+		fake_J_only = true;
 		GMT->common.R.active[RSET] = true;
 		GMT->common.J.active = false;
-		gmt_parse_common_options (GMT, "J", 'J', "X1i");
+		gmt_parse_common_options(GMT, "J", 'J', "x1i");	/* Issue #5635: lowercase x = 1 inch per unit so wesn span = inches; uppercase X1i forced rect to 1x1 inch regardless of image size */
 		gmt_adjust_refpoint (GMT, Ctrl->D.refpoint, Ctrl->D.dim, Ctrl->D.off, Ctrl->D.justify, PSL_BL);	/* Adjust refpoint to BL corner */
 		wesn[XHI] = Ctrl->D.refpoint->x + Ctrl->D.n_columns * Ctrl->D.dim[GMT_X];
 		wesn[YHI] = Ctrl->D.refpoint->y + Ctrl->D.n_rows * Ctrl->D.dim[GMT_Y];
 		gmt_M_memcpy (Rwesn, wesn, 4U, double);
-		strncpy (Jarg, "X1i", GMT_LEN128);
+		strncpy(Jarg, "x1i", GMT_LEN128);
 		if (gmt_map_setup (GMT, wesn)) {
 			if (free_GMT)
 				gmt_M_free (GMT, picture);
@@ -704,17 +706,22 @@ EXTERN_MSC int GMT_psimage (void *V_API, int mode, void *args) {
  	if (Ctrl->F.active)	/* Draw frame outlines */
 		gmt_draw_map_panel (GMT, Ctrl->D.refpoint->x + 0.5 * Ctrl->F.panel->width, Ctrl->D.refpoint->y + 0.5 * Ctrl->F.panel->height, 2U, Ctrl->F.panel);
 
-	/* Redo original -R -J so basemap can work */
-	GMT->common.J.active = false;
-	gmt_parse_common_options (GMT, "J", 'J', Jarg);
-	if (gmt_map_setup (GMT, Rwesn)) {
-		if (free_GMT)
-			gmt_M_free (GMT, picture);
-		else if (is_eps || did_gray)
-			PSL_free (picture);
-		gmt_M_str_free (file);
-		Return (GMT_PROJECTION_ERROR);
+	/* Redo original -R -J so basemap can work. Issue #5635: only needed when the original -R/-J were used
+	 * (else branch above swapped them out for a fake X1i to place the image, and now must restore them).
+	 * In the fake-J-only branch we never swapped, so re-parsing/-setup is redundant and corrupts state. */
+	if (!fake_J_only) {
+		GMT->common.J.active = false;
+		gmt_parse_common_options(GMT, "J", 'J', Jarg);
+		if (gmt_map_setup(GMT, Rwesn)) {
+			if (free_GMT)
+				gmt_M_free(GMT, picture);
+			else if (is_eps || did_gray)
+				PSL_free(picture);
+			gmt_M_str_free(file);
+			Return (GMT_PROJECTION_ERROR);
+		}
 	}
+	GMT->current.map.frame.order = GMT_BASEMAP_AFTER;	/* Issue #5635: ensure basemap renders AFTER content (frame, title) since this is the only call when fake_J_only */
 	gmt_map_basemap (GMT);	/* Draw basemap if requested */
 	gmt_plane_perspective (GMT, -1, 0.0);
 	gmt_plotend (GMT);