From a954a12134959eab351047489430c57f6281f6c7 Mon Sep 17 00:00:00 2001
From: Joseph Pingenot <bzrdude@digitasaru.net>
Date: Tue, 22 Jul 2008 21:55:55 -0500
Subject: [PATCH] It works!  Yay!

---
 graph.c       |    2 +-
 graph.h       |    4 ++--
 graphwidget.c |   29 +++++++++++++++++++++--------
 graphwidget.h |    3 +--
 4 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/graph.c b/graph.c
index a3a05da..6da0fb6 100644
--- a/graph.c
+++ b/graph.c
@@ -56,7 +56,7 @@ int graph_add_point(Graph* graph, double x, double y) {
   g_ptr_array_add(graph->points, (gpointer)point);
   if(graph->points->len == 1) {
     graph->maxx = graph->minx = x;
-    graph->maxy = graph->miny = x;
+    graph->maxy = graph->miny = y;
   }else{
     if(x > graph->maxx) graph->maxx = x;
     if(x < graph->minx) graph->minx = x;
diff --git a/graph.h b/graph.h
index 44ec6d7..33112a5 100644
--- a/graph.h
+++ b/graph.h
@@ -32,7 +32,7 @@
 typedef enum {SQUARE, CIRCLE, STAR, PLUS, MINUS, CROSS} graph_symbol;
 
 typedef struct _Graph {
-  GObject parent;
+  GObject parent_instance;
   /*Array of n_points sets of x,y coords*/
   GPtrArray *points;
   double maxx;
@@ -43,7 +43,7 @@ typedef struct _Graph {
 } Graph;
 
 typedef struct _GraphClass {
-  GObject parent;
+  GObjectClass parent_class;
 } GraphClass;
 
 #define GRAPH_TYPE (graph_get_type())
diff --git a/graphwidget.c b/graphwidget.c
index ed9cf4b..3dec40e 100644
--- a/graphwidget.c
+++ b/graphwidget.c
@@ -38,19 +38,29 @@ struct drawing_context {
   GtkWidget *widget;
   cairo_t *cr;
   double radius;
+  double xoffset;
+  double yoffset;
+  double xscaling;
+  double yscaling;
 };
 
 static void draw_point(gpointer data, gpointer user_data) {
   struct drawing_context *cxt = (struct drawing_context *) user_data;
   double *d = (double*)data;
-  cairo_arc(cxt->cr, d[0], d[1], cxt->radius, 0, 2*M_PI);
+  fprintf(stderr, "draw_point(x=%g(%g) y=%g(%g)) xscaling=%g yscaling=%g xoffset=%g yoffset=%g\n", d[0], (d[0] + cxt->xoffset)*cxt->xscaling, d[1], (d[1] + cxt->yoffset)*cxt->yscaling, cxt->xscaling, cxt->yscaling, cxt->xoffset, cxt->yoffset);
+  cairo_arc(cxt->cr, (d[0] + cxt->xoffset)*cxt->xscaling, (d[1] + cxt->yoffset)*cxt->yscaling, cxt->radius, 0, 2*M_PI);
+  cairo_set_source_rgb(cxt->cr, 1, 1, 1);
+  cairo_fill_preserve(cxt->cr);
+  cairo_set_source_rgb(cxt->cr, 0, 0, 0);
+  cairo_stroke(cxt->cr);
 }
 
 static void draw(GtkWidget *graph, cairo_t *cr) {
   struct drawing_context cxt;
+  GraphWidget *gw = GRAPH_WIDGET(graph);
   #ifdef DEBUG
-    fprintf(stderr, "draw(%d, %d)\n", graph, cr);
-    fprintf(stderr, "allocation.x=%d, allocation.y=%d, allocation.height=%d, allocation.width=%d\n", graph->allocation.x, graph->allocation.y, graph->allocation.height, graph->allocation.width);
+  fprintf(stderr, "draw(%d, %d)\n", graph, cr);
+  fprintf(stderr, "allocation.x=%d, allocation.y=%d, allocation.height=%d, allocation.width=%d\n", graph->allocation.x, graph->allocation.y, graph->allocation.height, graph->allocation.width);
   #endif
   double x0=graph->allocation.x;
   double y0=graph->allocation.y;
@@ -58,17 +68,20 @@ static void draw(GtkWidget *graph, cairo_t *cr) {
   double width=graph->allocation.width;
   cxt.widget = graph;
   cxt.cr = cr;
-  cxt.radius = ((height < width)? height : width)*0.01;
+  cxt.radius = 0.1;
+  cxt.xscaling = (gw->graph->points->len == 1)? 1 : (1/(gw->graph->maxx - gw->graph->minx));
+  cxt.yscaling = (gw->graph->points->len == 1)? 1 : (1/(gw->graph->maxy - gw->graph->miny));
+  cxt.xoffset = (gw->graph->points->len == 1)? (-gw->graph->minx/2) : (-gw->graph->minx);
+  cxt.yoffset = (gw->graph->points->len == 1)? (-gw->graph->miny/2) : (-gw->graph->miny);
   #ifdef DEBUG
   fprintf(stderr, "x0=%g, y0=%g, width=%g, height=%g\n", x0, y0, height, width);
   fprintf(stderr, "move_to(%d, %g->%g, %g->%g)\n", cr, graph_data[0], graph->allocation.x + graph_data[0]*(graph->allocation.width), graph_data[1], graph->allocation.y + graph_data[1]*(graph->allocation.height));
   #endif
   cairo_save(cr);
-  cairo_translate(cr, x0, y0);
-  cairo_scale(cr, width, height);
+  cairo_translate(cr, x0, y0+height);
+  cairo_scale(cr, width, -height);
+  cairo_set_line_width(cr, 0.05);
   g_ptr_array_foreach(GRAPH_WIDGET(graph)->graph->points, &draw_point, (gpointer)&cxt);
-  cairo_set_source_rgb(cr, 0, 0, 0);
-  cairo_stroke(cr);
   cairo_restore(cr);
 }
 
diff --git a/graphwidget.h b/graphwidget.h
index be1ebaa..3b57af9 100644
--- a/graphwidget.h
+++ b/graphwidget.h
@@ -33,13 +33,12 @@
 #include <graph.h>
 
 typedef struct _GraphWidget {
-  GtkDrawingArea parent;
+  GtkDrawingArea parent_instance;
   Graph *graph;
 } GraphWidget;
 
 typedef struct _GraphWidgetClass {
   GtkDrawingAreaClass parent_class;
-  
 } GraphWidgetClass;
 
 #define GRAPH_WIDGET_TYPE (graph_widget_get_type())
-- 
1.7.9.5