From: Joseph Pingenot <bzrdude@digitasaru.net>
Date: Sun, 27 Jul 2008 20:49:46 +0000 (-0500)
Subject: * OK.  Now *this* seems to work great.
X-Git-Url: http://git.maemo.org/git/?p=scdataviz;a=commitdiff_plain;h=23aee1377a3f8d174451eaadbcdf22032978172b

* OK.  Now *this* seems to work great.
* Next up, the actual labels.
---

diff --git a/graph.c b/graph.c
index 647c310..891fc6f 100644
--- a/graph.c
+++ b/graph.c
@@ -209,8 +209,8 @@ struct graph_axis* autoset_axis(Graph* g, GString* title, double min, double max
       stop_mag = copysign(pow(10, ceil(log10(max))), max);
     if(stop_mag == start_mag) stop_mag *= 10;
     axis->major=10;
-    axis->minor=9;
-    axis->subminor=0;
+    axis->minor=1;
+    axis->subminor=4;
     axis->major_start=start_mag;
     axis->major_step=(stop_mag - start_mag)/(axis->major);
   }
diff --git a/graphwidget.c b/graphwidget.c
index 132b4a1..4ecc55a 100644
--- a/graphwidget.c
+++ b/graphwidget.c
@@ -35,13 +35,18 @@
 G_DEFINE_TYPE(GraphWidget, graph_widget, GTK_TYPE_DRAWING_AREA);
 
 #define INSET_PERCENT 0.1
-#define TITLE_PERCENT 0.1
+#define TITLE_PERCENT 0.15
 #define DEBUG_DRAW_AXIS
 
 struct drawing_context {
   GtkWidget *widget;
   cairo_t *cr;
   double radius;
+  double xoffset;
+  double yoffset;
+  double xscaling;
+  double yscaling;
+  /*Semi-normalized maxima*/
   double xmax;
   double ymax;
   cairo_matrix_t data_scale;
@@ -51,11 +56,8 @@ struct drawing_context {
 static void draw_point(gpointer data, gpointer user_data) {
   struct drawing_context *cxt = user_data;
   struct graph_point *pt = data;
-  cairo_save(cxt->cr);
-  cairo_transform(cxt->cr, cxt->data_xlat);
-  cairo_transform(cxt->cr, cxt->data_scale);
-  double x = pt->x;
-  double y = pt->y;
+  double x = (pt->x + cxt->xoffset)*cxt->xscaling;
+  double y = (pt->y + cxt->yoffset)*cxt->yscaling;
   cairo_move_to(cxt->cr, x, y);
   cairo_arc(cxt->cr, x, y, cxt->radius, 0, 2*M_PI);
   if(pt->label != NULL) {
@@ -64,40 +66,32 @@ static void draw_point(gpointer data, gpointer user_data) {
     cairo_show_text(cxt->cr, pt->label->str);
     cairo_restore(cxt->cr);
   }
-  cairo_restore;
 }
 
 static void draw_lines(gpointer data, gpointer user_data) {
   struct drawing_context *cxt = user_data;
   struct graph_line *l = data;
-  cairo_save(cxt->cr);
-  cairo_transform(cxt->cr, cxt->data_xlat);
-  cairo_transform(cxt->cr, cxt->data_scale);
-  double p0_x = l->p0_x;
-  double p0_y = l->p0_y;
-  double p1_x = l->p1_x;
-  double p1_y = l->p1_y;
-  double p2_x = l->p2_x;
-  double p2_y = l->p2_y;
-  double p3_x = l->p3_x;
-  double p3_y = l->p3_y;
+  double p0_x = (l->p0_x + cxt->xoffset)*cxt->xscaling;
+  double p0_y = (l->p0_y + cxt->yoffset)*cxt->yscaling;
+  double p1_x = (l->p1_x + cxt->xoffset)*cxt->xscaling;
+  double p1_y = (l->p1_y + cxt->yoffset)*cxt->yscaling;
+  double p2_x = (l->p2_x + cxt->xoffset)*cxt->xscaling;
+  double p2_y = (l->p2_y + cxt->yoffset)*cxt->yscaling;
+  double p3_x = (l->p3_x + cxt->xoffset)*cxt->xscaling;
+  double p3_y = (l->p3_y + cxt->yoffset)*cxt->yscaling;
   #ifdef DEBUG_DRAW
   fprintf(stderr, "draw_lines: p0_x=%g, p0_y=%g, p1_x=%g, p1_y=%g, p2_x=%g, p2_y=%g, p3_x=%g, p3_y=%g\n", p0_x, p0_y, p1_x, p1_y, p2_x, p2_y, p3_x, p3_y);
   #endif
   cairo_move_to(cxt->cr, p0_x, p0_y);
   cairo_curve_to(cxt->cr, p1_x, p1_y, p2_x, p2_y, p3_x, p3_y);
-  cairo_restore(cxt->cr);
 }
 
-static void draw_axis(struct drawing_context* cxt, struct graph_axis *axis) {
-  cairo_save(cxt->cr);
-  cairo_transform(cxt->cr, cxt->data_xlat);
-  cairo_transform(cxt->cr, cxt->data_scale);
+static void draw_axis(struct drawing_context* cxt, struct graph_axis *axis, double scaling, double offset, double max) {
   #ifdef DEBUG_DRAW_AXIS
   fprintf(stderr, "draw_axis; major_start=%g, major_step=%g, >major=%d, minor=%d, subminor=%d, label=%s\n", axis->major_start, axis->major_step, axis->major, axis->minor, axis->subminor, axis->title->str);
   #endif
   cairo_move_to(cxt->cr, 0, 0);
-  cairo_line_to(cxt->cr, 1, 0);
+  cairo_line_to(cxt->cr, max, 0);
   register int i, j, k;
   register double pos, mpos, smpos;
   for(i=0; i<axis->major; i++) {
@@ -123,7 +117,6 @@ static void draw_axis(struct drawing_context* cxt, struct graph_axis *axis) {
   pos=i*axis->major_step + axis->major_start;
   cairo_move_to(cxt->cr, (pos + offset)*scaling, 0);
   cairo_line_to(cxt->cr, (pos + offset)*scaling, 0.05);
-  cairo_restore(cxt->cr);
 }
 
 static void draw(GtkWidget *graph, cairo_t *cr) {
@@ -167,9 +160,9 @@ static void draw(GtkWidget *graph, cairo_t *cr) {
     axis_inset = ((effective_height > effective_width)?effective_width:effective_height)*TITLE_PERCENT;
     effective_height -= axis_inset;
     effective_width -= axis_inset;
-  }elsif(gw->graph->xaxis != NULL) {
+  }else if(gw->graph->xaxis != NULL) {
     effective_height -= effective_height*TITLE_PERCENT;
-  }elsif(gw->graph->yaxis != NULL) {
+  }else if(gw->graph->yaxis != NULL) {
     effective_width -= effective_width*TITLE_PERCENT;
   }
   if(effective_width > effective_height) {
@@ -184,13 +177,27 @@ static void draw(GtkWidget *graph, cairo_t *cr) {
   double yscaling = (gw->graph->points->len == 1)? cxt.ymax : (cxt.ymax/(maxy-miny));
   double xoffset = (gw->graph->points->len == 1)? (-minx/2) : (-minx);
   double yoffset = (gw->graph->points->len == 1)? (-miny/2) : (-miny);
+  /*Finish up our context information.*/
+  cxt.xscaling = (gw->graph->points->len == 1)? cxt.xmax : (cxt.xmax/(maxx - minx));
+  cxt.yscaling = (gw->graph->points->len == 1)? cxt.ymax : (cxt.ymax/(maxy - miny));
+  cxt.xoffset = (gw->graph->points->len == 1)? (-minx/2) : (-minx);
+  cxt.yoffset = (gw->graph->points->len == 1)? (-miny/2) : (-miny);
   cairo_matrix_translate(&(cxt.data_xlat), xoffset, yoffset);
   cairo_matrix_scale(&(cxt.data_scale), xscaling, yscaling);
+  #ifdef DEBUG
+  fprintf(stderr, "minx=%g, maxx=%g, miny=%g, maxy=%g, xscaling=%g, yscaling=%g, xoffset=%g, yoffset=%g\n", minx, maxx, miny, maxy, cxt.xscaling, cxt.yscaling, cxt.xoffset, cxt.yoffset);
+  fprintf(stderr, "x0=%g, y0=%g, width=%g, height=%g\n", x0, y0, height, width);
+  fprintf(stderr, "translate=(%g, %g)\n", x0 + ((width>height)?(width-height)/2.0:0), y0+((width > height)?height:width) + ((height>width)?(height-width)/2.0:0));
+#endif
+  double offset_height =  ((width>=height)?height*INSET_PERCENT:0);;
+  double offset_width = ((height>=width)?width*INSET_PERCENT:0); 
+  double inset_height = height - offset_height;
+  double inset_width = width - offset_width;
   cairo_save(cr);
-  cairo_translate(cr, effective_width - inset/2, effective_height - inset/2);
-  cairo_scale(cr, effective_width, effective_height);
+  cairo_translate(cr, x0 + (width - effective_width) - inset/2, y0 + effective_height + inset/2);
+  cairo_scale(cr, effective_width/cxt.xmax, -effective_height/cxt.ymax);
   cairo_set_line_width(cr, 0.005);
-  cairo_select_font_face (cr, "Sans Serif",
+  cairo_select_font_face (cr, "Georgia",
 			  CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_BOLD);
   cairo_set_font_size (cr, 0.05);
   if(gw->graph->lines != NULL) {
@@ -203,12 +210,12 @@ static void draw(GtkWidget *graph, cairo_t *cr) {
   cairo_set_source_rgb(cr, 0, 0, 0);
   g_ptr_array_foreach(gw->graph->points, &draw_point, (gpointer)&cxt);
   if(gw->graph->xaxis != NULL) 
-    draw_axis(&cxt, gw->graph->xaxis, cxt.xscaling, cxt.xoffset);
+    draw_axis(&cxt, gw->graph->xaxis, cxt.xscaling, cxt.xoffset, cxt.xmax);
   if(gw->graph->yaxis != NULL) {
     cairo_save(cr);
     cairo_matrix_t matrix = { .xx=0, .xy = 1, .x0 = 0, .yx = 1, .yy = 0, .y0 = 0 };
     cairo_transform(cr, &matrix);
-    draw_axis(&cxt, gw->graph->yaxis, cxt.yscaling, cxt.yoffset);
+    draw_axis(&cxt, gw->graph->yaxis, cxt.yscaling, cxt.yoffset, cxt.ymax);
     cairo_restore(cr);
   }
   cairo_stroke(cr);