aboutsummaryrefslogtreecommitdiff
path: root/liblogdiag
diff options
context:
space:
mode:
authorPřemysl Janouch <p.janouch@gmail.com>2011-02-10 06:03:41 +0100
committerPřemysl Janouch <p.janouch@gmail.com>2011-02-10 06:03:41 +0100
commitd96acedcdbab4e8c0ce54d7a3c5c28334557adbd (patch)
tree8ba8a955a781f1f141a5c2de74467254b6054a62 /liblogdiag
parent39fb4bb56f5c5644aba0603c01cbad112b66273c (diff)
downloadlogdiag-d96acedcdbab4e8c0ce54d7a3c5c28334557adbd.tar.gz
logdiag-d96acedcdbab4e8c0ce54d7a3c5c28334557adbd.tar.xz
logdiag-d96acedcdbab4e8c0ce54d7a3c5c28334557adbd.zip
Speed up drawing of the grid.
Diffstat (limited to 'liblogdiag')
-rw-r--r--liblogdiag/ld-canvas.c59
1 files changed, 41 insertions, 18 deletions
diff --git a/liblogdiag/ld-canvas.c b/liblogdiag/ld-canvas.c
index f89cbfd..f568f5f 100644
--- a/liblogdiag/ld-canvas.c
+++ b/liblogdiag/ld-canvas.c
@@ -216,6 +216,7 @@ static gdouble ld_canvas_get_scale_in_px (LdCanvas *self);
static void ld_canvas_color_set (LdCanvasColor *color,
gdouble r, gdouble g, gdouble b, gdouble a);
static void ld_canvas_color_apply (LdCanvasColor *color, cairo_t *cr);
+static guint32 ld_canvas_color_to_cairo_argb (LdCanvasColor *color);
static gdouble point_to_line_segment_distance
(const LdPoint *point, const LdPoint *p1, const LdPoint *p2);
@@ -997,6 +998,15 @@ ld_canvas_color_apply (LdCanvasColor *color, cairo_t *cr)
cairo_set_source_rgba (cr, color->r, color->g, color->b, color->a);
}
+static guint32
+ld_canvas_color_to_cairo_argb (LdCanvasColor *color)
+{
+ return (guint) (color->a * 255) << 24
+ | (guint) (color->r * color->a * 255) << 16
+ | (guint) (color->g * color->a * 255) << 8
+ | (guint) (color->b * color->a * 255);
+}
+
static gdouble
point_to_line_segment_distance
(const LdPoint *point, const LdPoint *p1, const LdPoint *p2)
@@ -1998,7 +2008,10 @@ draw_grid (GtkWidget *widget, DrawData *data)
gint grid_factor;
gdouble x_init, y_init;
gdouble x, y;
- gdouble x_round, y_round;
+ cairo_surface_t *grid_surface;
+ gint stride;
+ unsigned char *pixels;
+ guint32 color;
grid_step = data->scale;
grid_factor = 1;
@@ -2008,9 +2021,13 @@ draw_grid (GtkWidget *widget, DrawData *data)
grid_factor *= 5;
}
- ld_canvas_color_apply (COLOR_GET (data->self, COLOR_GRID), data->cr);
- cairo_set_line_width (data->cr, 1);
- cairo_set_line_cap (data->cr, CAIRO_LINE_CAP_ROUND);
+ /* Paint manually on our own raster surface for speed. */
+ stride = cairo_format_stride_for_width
+ (CAIRO_FORMAT_ARGB32, data->exposed_rect.width);
+ pixels = g_malloc0 (stride * data->exposed_rect.height);
+ grid_surface = cairo_image_surface_create_for_data
+ (pixels, CAIRO_FORMAT_ARGB32,
+ data->exposed_rect.width, data->exposed_rect.height, stride);
/* Get coordinates of the top-left point. */
ld_canvas_widget_to_diagram_coords (data->self,
@@ -2024,20 +2041,26 @@ draw_grid (GtkWidget *widget, DrawData *data)
ld_canvas_diagram_to_widget_coords (data->self,
x_init, y_init, &x_init, &y_init);
- /* Iterate over all the points. */
- for (x = x_init; x <= data->exposed_rect.x + data->exposed_rect.width;
- x += grid_step)
- {
- for (y = y_init; y <= data->exposed_rect.y + data->exposed_rect.height;
- y += grid_step)
- {
- x_round = floor (x) + 0.5;
- y_round = floor (y) + 0.5;
- cairo_move_to (data->cr, x_round, y_round);
- cairo_line_to (data->cr, x_round, y_round);
- }
- }
- cairo_stroke (data->cr);
+ x_init -= data->exposed_rect.x;
+ y_init -= data->exposed_rect.y;
+
+ while (x_init < 0)
+ x_init += grid_step;
+ while (y_init < 0)
+ y_init += grid_step;
+
+ color = ld_canvas_color_to_cairo_argb (COLOR_GET (data->self, COLOR_GRID));
+
+ for (x = x_init; x < data->exposed_rect.width; x += grid_step)
+ for (y = y_init; y < data->exposed_rect.height; y += grid_step)
+ *((guint32 *) (pixels + stride * (gint) y) + (gint) x) = color;
+
+ cairo_set_source_surface (data->cr, grid_surface,
+ data->exposed_rect.x, data->exposed_rect.y);
+ cairo_paint (data->cr);
+
+ cairo_surface_destroy (grid_surface);
+ g_free (pixels);
}
static void