gseisviewaxisz.c

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                start_label += labels_step;
            end_label = ((gint)(last_value / labels_step)) * labels_step;
            while (end_label > last_value)
                end_label -= labels_step;
            labels_num = (end_label - start_label) / labels_step + 1;
            labels_step_object = labels_step * value_to_object_scale;
            for (;;) {
                if (ten_factor < 2.0)
                    ten_factor = 2.0;
                else if (ten_factor < 2.4)
                    ten_factor = 2.5;
                else if (ten_factor < 4.0)
                    ten_factor = 5.0;
                else {
                    power_of_ten++;
                    ten_powered = pow (10, power_of_ten);
                    ten_factor = 1.0;
                }
                labels_residue = ten_powered * ten_factor - (gint)(ten_powered * ten_factor);
                labels_precision = 0;
                while (labels_residue - (gint)(labels_residue)) {
                    labels_precision++;
                    labels_residue *= 10.0;
                }
                if (G_SEIS_VIEW_AXIS_Z_FLOAT == private->format &&
                    labels_precision <= private->precision)
                    break;
                else if (0 == labels_precision)
                    break;
            }
        }
        start_label_object = data_visibility->fast_start_object + (start_label - first_value) * value_to_object_scale;

        private->display_list_base = glGenLists (1);

        glNewList (private->display_list_base, GL_COMPILE);

        glPushAttrib (GL_LINE_BIT | GL_LIST_BIT);
        glListBase (private->font_list_base);
        /* Preceding label - might be visible partially */
        gdouble preceding_label = start_label - labels_step;
        if ((preceding_label >= private->min_value && preceding_label <= private->max_value) ||
            (preceding_label <= private->min_value && preceding_label >= private->max_value)) {
            if (G_SEIS_VIEW_AXIS_Z_INTEGER == private->format)
                g_snprintf (gbuffer, G_ASCII_DTOSTR_BUF_SIZE, private->gformat, (gint)(start_label - labels_step));
            else
                g_ascii_formatd (gbuffer, G_ASCII_DTOSTR_BUF_SIZE, private->gformat, start_label - labels_step);
            for (label_strlen = 0; gbuffer[label_strlen] != '\0'; label_strlen++);

            if (self->type == G_SEIS_VIEW_AXIS_RIGHT)
                glRasterPos2f (slow_start_object - tick_size_object + margin_object,
                               start_label_object);
            else
                glRasterPos2f (margin_object + text_width_object * (private->label_max_strlen - label_strlen) / (gdouble)private->label_max_strlen,
                               start_label_object);
            glBitmap (0, 0, 0, 0, 0, labels_step_object / fast_pixel_to_object_scale + private->text_height_screen / -4.0, NULL);
            glCallLists (label_strlen, GL_UNSIGNED_BYTE, (GLubyte*)gbuffer);
        }
        /* All visible labels */
        for (i = 0; i < labels_num; i++) {
            if (G_SEIS_VIEW_AXIS_Z_INTEGER == private->format)
                g_snprintf (gbuffer, G_ASCII_DTOSTR_BUF_SIZE, private->gformat, (gint)(start_label + i * labels_step));
            else
                g_ascii_formatd (gbuffer, G_ASCII_DTOSTR_BUF_SIZE, private->gformat, start_label + i * labels_step);
            /* Text length */
            for (label_strlen = 0; gbuffer[label_strlen] != '\0'; label_strlen++);

            if (self->type == G_SEIS_VIEW_AXIS_RIGHT)
                glRasterPos2f (slow_start_object - tick_size_object + margin_object,
                               start_label_object + i * labels_step_object);
            else
                glRasterPos2f (margin_object + text_width_object * (private->label_max_strlen - label_strlen) / (gdouble)private->label_max_strlen,
                               start_label_object + i * labels_step_object);
            glBitmap (0, 0, 0, 0, 0, private->text_height_screen / -4.0, NULL);
            glCallLists (label_strlen, GL_UNSIGNED_BYTE, (GLubyte*)gbuffer);

            /* Tick */
            glBegin (GL_LINES);
            glVertex2f (slow_start_object - tick_size_object, start_label_object + i * labels_step_object);
            glVertex2f (slow_start_object, start_label_object + i * labels_step_object);
            glEnd ();
        }
        /* Trailing label - might be visible partially */
        gdouble trailing_label = start_label + labels_num * labels_step;
        if ((trailing_label <= private->max_value && trailing_label >= private->min_value) ||
            (trailing_label >= private->max_value && trailing_label <= private->min_value)) {
            if (G_SEIS_VIEW_AXIS_Z_INTEGER == private->format)
                g_snprintf (gbuffer, G_ASCII_DTOSTR_BUF_SIZE, private->gformat, (gint)(start_label + labels_num * labels_step));
            else
                g_ascii_formatd (gbuffer, G_ASCII_DTOSTR_BUF_SIZE, private->gformat, start_label + labels_num * labels_step);
            for (label_strlen = 0; gbuffer[label_strlen] != '\0'; label_strlen++);
            if (self->type == G_SEIS_VIEW_AXIS_RIGHT)
                glRasterPos2f (slow_start_object - tick_size_object + margin_object,
                               start_label_object + (labels_num - 1) * labels_step_object);
            else
                glRasterPos2f (margin_object + text_width_object * (private->label_max_strlen - label_strlen) / (gdouble)private->label_max_strlen,
                               start_label_object + (labels_num - 1) * labels_step_object);
            glBitmap (0, 0, 0, 0, 0, -labels_step_object / fast_pixel_to_object_scale + private->text_height_screen / -4.0, NULL);
            glCallLists (label_strlen, GL_UNSIGNED_BYTE, (GLubyte*)gbuffer);
        }
        /* Border line */
        glLineWidth (2);
        glBegin (GL_LINES);
        glVertex2f (slow_start_object, data_visibility->fast_start_object);
        glVertex2f (slow_start_object, data_visibility->fast_start_object + data_visibility->fast_size_object);
        glEnd ();
        glPopAttrib ();
        glEndList ();
        private->redisplay = FALSE;
        if (private->rendering_mutex)
            g_mutex_unlock (private->rendering_mutex);
    }

    if (private->display_list_base)
        glCallList (private->display_list_base);
}

static void g_seis_view_axis_z_resize_event (GSeisViewAxis *self, GtkWidget *seis_view_gl,
                                             GSeisViewDataVisibility *data_visibility) {
    GSeisViewAxisZPrivate *private = G_SEIS_VIEW_AXIS_Z_GET_PRIVATE (G_SEIS_VIEW_AXIS_Z (self));

    private->redisplay = TRUE;
}

void g_seis_view_axis_z_set_min_max (GSeisViewAxisZ *axis, gdouble min_value,
                                     gdouble values_step, guint32 values_num) {
    GSeisViewAxisZPrivate *private = G_SEIS_VIEW_AXIS_Z_GET_PRIVATE (axis);

    if (private->rendering_mutex)
        g_mutex_lock (private->rendering_mutex);

    private->min_value = min_value;
    private->values_step = values_step;
    private->values_num = values_num;
    private->max_value = min_value + (values_num - 1) * values_step;

    if (private->rendering_mutex)
        g_mutex_unlock (private->rendering_mutex);
}

void g_seis_view_axis_z_set_format (GSeisViewAxisZ *axis, GSeisViewAxisZFormat format) {
    GSeisViewAxisZPrivate *private = G_SEIS_VIEW_AXIS_Z_GET_PRIVATE (axis);

    if (private->rendering_mutex)
        g_mutex_lock (private->rendering_mutex);

    private->format = format;

    if (private->rendering_mutex)
        g_mutex_unlock (private->rendering_mutex);
}

void g_seis_view_axis_z_set_precision (GSeisViewAxisZ *axis, guint8 precision) {
    GSeisViewAxisZPrivate *private = G_SEIS_VIEW_AXIS_Z_GET_PRIVATE (axis);

    if (private->rendering_mutex)
        g_mutex_lock (private->rendering_mutex);

    private->precision = precision;
    if (private->precision > 6)
        private->precision = 6;

    if (private->rendering_mutex)
        g_mutex_unlock (private->rendering_mutex);
}

void g_seis_view_axis_z_set_font (GSeisViewAxisZ *axis, const gchar *font_name) {
    GSeisViewAxisZPrivate *private = G_SEIS_VIEW_AXIS_Z_GET_PRIVATE (axis);

    if (private->rendering_mutex)
        g_mutex_lock (private->rendering_mutex);

    if (private->font_name)
        g_free (private->font_name);

    private->font_name = g_strdup (font_name);

    if (private->font_desc)
        pango_font_description_free (private->font_desc);

    private->rebuild_font = TRUE;

    private->font_desc = pango_font_description_from_string (private->font_name);

    if (private->rendering_mutex)
        g_mutex_unlock (private->rendering_mutex);
}

void g_seis_view_axis_z_set_fg_color (GSeisViewAxisZ *axis, const GSeisColor *fg_color) {
    GSeisViewAxisZPrivate *private = G_SEIS_VIEW_AXIS_Z_GET_PRIVATE (axis);

    if (private->rendering_mutex)
        g_mutex_lock (private->rendering_mutex);

    private->fg_color.red = fg_color->red;
    private->fg_color.green = fg_color->green;
    private->fg_color.blue = fg_color->blue;

    if (private->rendering_mutex)
        g_mutex_unlock (private->rendering_mutex);

    g_object_notify (G_OBJECT (axis), "fg_color");
}

void g_seis_view_axis_z_set_bg_color (GSeisViewAxisZ *axis, const GSeisColor *bg_color) {
    GSeisViewAxisZPrivate *private = G_SEIS_VIEW_AXIS_Z_GET_PRIVATE (axis);

    if (private->rendering_mutex)
        g_mutex_lock (private->rendering_mutex);

    private->bg_color.red = bg_color->red;
    private->bg_color.green = bg_color->green;
    private->bg_color.blue = bg_color->blue;

    if (private->rendering_mutex)
        g_mutex_unlock (private->rendering_mutex);

    g_object_notify (G_OBJECT (axis), "bg_color");
}

static void g_seis_view_axis_z_reshape (GSeisViewAxis *axis, GtkWidget *seis_view_gl) {
    GSeisViewAxisZPrivate *private = G_SEIS_VIEW_AXIS_Z_GET_PRIVATE (G_SEIS_VIEW_AXIS_Z (axis));
    gchar gbuffer[G_ASCII_DTOSTR_BUF_SIZE];
    guint max_text_width_screen = 0, max_text_height_screen = 0;
    guint text_width_screen = 0, text_height_screen = 0;
    gint16 label_strlen = 0, label_max_strlen = 0;
    gfloat value;

    if (private->rendering_mutex)
        g_mutex_lock (private->rendering_mutex);

    if (G_SEIS_VIEW_AXIS_Z_INTEGER == private->format)
        g_snprintf (private->gformat, G_ASCII_DTOSTR_BUF_SIZE, "%%%s", G_GINT32_FORMAT);
    else
        g_snprintf (private->gformat, G_ASCII_DTOSTR_BUF_SIZE, "%%.%"G_GUINT32_FORMAT"f", (guint32)private->precision);
    gbuffer[0] = '\0';

    if (GTK_WIDGET_REALIZED (seis_view_gl)) {
        PangoLayout *layout = gtk_widget_create_pango_layout (seis_view_gl, gbuffer);
        pango_layout_set_width (layout, -1);
        pango_layout_set_indent (layout, 0);
        pango_layout_set_spacing (layout, 0);
        pango_layout_set_justify (layout, FALSE);
        pango_layout_set_font_description (layout, private->font_desc);

        /* Render values and get their dimensions in pixels */
        for (value = private->min_value; value <= private->max_value; value += private->values_step) {
            if (G_SEIS_VIEW_AXIS_Z_INTEGER == private->format)
                g_snprintf (gbuffer, G_ASCII_DTOSTR_BUF_SIZE, private->gformat, (gint)value);
            else
                g_ascii_formatd (gbuffer, G_ASCII_DTOSTR_BUF_SIZE, private->gformat, value);
            for (label_strlen = 0; gbuffer[label_strlen] != '\0'; label_strlen++);
            if (label_strlen > label_max_strlen)
                label_max_strlen = label_strlen;

            pango_layout_set_text (layout, gbuffer, -1);
            pango_layout_get_pixel_size (layout, &text_width_screen, &text_height_screen);
            if (text_width_screen > max_text_width_screen)
                max_text_width_screen = text_width_screen;
            if (text_height_screen > max_text_height_screen)
                max_text_height_screen = text_height_screen;
        }

        private->label_max_strlen = label_max_strlen;
        private->text_width_screen = max_text_width_screen;
        private->text_height_screen = max_text_height_screen;
        g_object_unref (layout);