Add scrollable pane widget to textscreen library.

Subversion-branch: /trunk/chocolate-doom
Subversion-revision: 1437

7 files changed, 493 insertions, 4 deletions

diff --git a/textscreen/Makefile.am b/textscreen/Makefile.am
index 76fe8f0f..d09538fd 100644
--- a/textscreen/Makefile.am
+++ b/textscreen/Makefile.am
@@ -19,6 +19,7 @@ libtextscreen_a_SOURCES =                                 \
 	txt_button.c             txt_button.h             \
 	txt_label.c              txt_label.h              \
 	txt_radiobutton.c        txt_radiobutton.h        \
+        txt_scrollpane.c         txt_scrollpane.h         \
 	txt_separator.c          txt_separator.h          \
 	txt_spinctrl.c           txt_spinctrl.h           \
 	txt_sdl.c                txt_sdl.h                \
diff --git a/textscreen/examples/guitest.c b/textscreen/examples/guitest.c
index 94483236..2a4d78cb 100644
--- a/textscreen/examples/guitest.c
+++ b/textscreen/examples/guitest.c
@@ -119,7 +119,7 @@ void SetupWindow(void)
     }
 
     UpdateLabel(NULL, NULL);
-                                     
+
     TXT_AddWidget(window, TXT_NewButton2("Close Window", CloseWindow, NULL));
 
     pwn = TXT_NewWindowAction(KEY_F1, "PWN!");
@@ -133,8 +133,9 @@ void Window2(void)
 {
     txt_window_t *window;
     txt_table_t *table;
+    txt_scrollpane_t *scrollpane;
     int i;
-    
+
     window = TXT_NewWindow("Another test");
     TXT_SetWindowPosition(window, 
                           TXT_HORIZ_RIGHT, 
@@ -155,6 +156,22 @@ void Window2(void)
     TXT_AddWidget(table, TXT_NewIntInputBox(&numbox_value, 10));
     TXT_AddWidget(table, TXT_NewLabel("Spin control:"));
     TXT_AddWidget(table, TXT_NewSpinControl(&numbox_value, 0, 15));
+
+    TXT_AddWidget(window, TXT_NewSeparator("Scroll pane test"));
+    scrollpane = TXT_NewScrollPane(40, 5, TXT_NewLabel(
+        "This is a scrollable pane. The contents\n"
+        "of this box are larger than the box\n"
+        "itself, but it can be scrolled around\n"
+        "to explore the full contents.\n"
+        "\n"
+        "Scrollable panes can be scrolled both\n"
+        "vertically and horizontally. They\n"
+        "can contain any widget. The scroll bars\n"
+        "appear automatically as needed.\n"
+        "\n"
+        "This is a very long line of text that forces a horizontal scrollbar"
+    ));
+    TXT_AddWidget(window, scrollpane);
 }
 
 int main(int argc, char *argv[])
diff --git a/textscreen/textscreen.h b/textscreen/textscreen.h
index dcefa409..c01e96c8 100644
--- a/textscreen/textscreen.h
+++ b/textscreen/textscreen.h
@@ -32,6 +32,7 @@
 #include "txt_inputbox.h"
 #include "txt_label.h"
 #include "txt_radiobutton.h"
+#include "txt_scrollpane.h"
 #include "txt_separator.h"
 #include "txt_spinctrl.h"
 #include "txt_strut.h"
diff --git a/textscreen/txt_gui.c b/textscreen/txt_gui.c
index 679d66fa..e7f0472e 100644
--- a/textscreen/txt_gui.c
+++ b/textscreen/txt_gui.c
@@ -252,6 +252,101 @@ void TXT_DrawString(char *s)
     TXT_GotoXY(x + strlen(s), y);
 }
 
+void TXT_DrawHorizScrollbar(int x, int y, int w, int cursor, int range)
+{
+    int x1;
+    int cursor_x;
+
+    if (!VALID_Y(y))
+    {
+        return;
+    }
+
+    TXT_FGColor(TXT_COLOR_BLACK);
+    TXT_BGColor(TXT_COLOR_GREY, 0);
+
+    TXT_GotoXY(x, y);
+    TXT_PutChar('\x1b');
+
+    cursor_x = x + 1;
+
+    if (range > 1)
+    {
+        cursor_x += (cursor * (w - 3)) / (range - 1);
+    }
+
+    if (cursor_x > x + w - 2)
+    {
+        cursor_x = x + w - 2;
+    }
+
+    for (x1=x+1; x1<x+w-1; ++x1)
+    {
+        if (VALID_X(x1))
+        {
+            if (x1 == cursor_x)
+            {
+                TXT_PutChar('\xdb');
+            }
+            else
+            {
+                TXT_PutChar('\xb1');
+            }
+        }
+    }
+
+    TXT_PutChar('\x1a');
+}
+
+void TXT_DrawVertScrollbar(int x, int y, int h, int cursor, int range)
+{
+    int y1;
+    int cursor_y;
+
+    if (!VALID_X(x))
+    {
+        return;
+    }
+
+    TXT_FGColor(TXT_COLOR_BLACK);
+    TXT_BGColor(TXT_COLOR_GREY, 0);
+
+    TXT_GotoXY(x, y);
+    TXT_PutChar('\x18');
+
+    cursor_y = y + 1;
+
+    if (cursor_y > y + h - 2)
+    {
+        cursor_y = y + h - 2;
+    }
+
+    if (range > 1)
+    {
+        cursor_y += (cursor * (h - 3)) / (range - 1);
+    }
+
+    for (y1=y+1; y1<y+h-1; ++y1)
+    {
+        if (VALID_Y(y1))
+        {
+            TXT_GotoXY(x, y1);
+
+            if (y1 == cursor_y)
+            {
+                TXT_PutChar('\xdb');
+            }
+            else
+            {
+                TXT_PutChar('\xb1');
+            }
+        }
+    }
+
+    TXT_GotoXY(x, y + h - 1);
+    TXT_PutChar('\x19');
+}
+
 void TXT_InitClipArea(void)
 {
     if (cliparea == NULL)
@@ -283,13 +378,17 @@ void TXT_PushClipArea(int x1, int x2, int y1, int y2)
         newarea->x1 = x1;
     if (x2 < newarea->x2)
         newarea->x2 = x2;
-    if (y1 > newarea->x1)
+    if (y1 > newarea->y1)
         newarea->y1 = y1;
     if (y2 < newarea->y2)
         newarea->y2 = y2;
 
+#if 0
+    printf("New scrollable area: %i,%i-%i,%i\n", x1, y1, x2, y2);
+#endif
+
     // Hook into the list
-    
+
     newarea->next = cliparea;
     cliparea = newarea;
 }
diff --git a/textscreen/txt_gui.h b/textscreen/txt_gui.h
index 5c120f6c..3795c65a 100644
--- a/textscreen/txt_gui.h
+++ b/textscreen/txt_gui.h
@@ -32,6 +32,9 @@ void TXT_DrawWindowFrame(char *title, int x, int y, int w, int h);
 void TXT_DrawSeparator(int x, int y, int w);
 void TXT_DrawString(char *s);
 
+void TXT_DrawHorizScrollbar(int x, int y, int w, int cursor, int range);
+void TXT_DrawVertScrollbar(int x, int y, int h, int cursor, int range);
+
 void TXT_InitClipArea(void);
 void TXT_PushClipArea(int x1, int x2, int y1, int y2);
 void TXT_PopClipArea(void);
diff --git a/textscreen/txt_scrollpane.c b/textscreen/txt_scrollpane.c
new file mode 100644
index 00000000..9049413b
--- /dev/null
+++ b/textscreen/txt_scrollpane.c
@@ -0,0 +1,326 @@
+// Emacs style mode select   -*- C++ -*- 
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 2009 Simon Howard
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License
+// as published by the Free Software Foundation; either version 2
+// of the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+// 02111-1307, USA.
+//
+
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+
+#include "txt_scrollpane.h"
+#include "txt_gui.h"
+#include "txt_io.h"
+#include "txt_main.h"
+
+#define SCROLLBAR_VERTICAL   (1 << 0)
+#define SCROLLBAR_HORIZONTAL (1 << 1)
+
+static int FullWidth(txt_scrollpane_t *scrollpane)
+{
+    if (scrollpane->child != NULL)
+    {
+        return scrollpane->child->w;
+    }
+    else
+    {
+        return 0;
+    }
+}
+
+static int FullHeight(txt_scrollpane_t *scrollpane)
+{
+    if (scrollpane->child != NULL)
+    {
+        return scrollpane->child->h;
+    }
+    else
+    {
+        return 0;
+    }
+}
+
+// Calculate which scroll bars the pane needs.
+
+static int NeedsScrollbars(txt_scrollpane_t *scrollpane)
+{
+    int result;
+
+    result = 0;
+
+    if (FullWidth(scrollpane) > scrollpane->w)
+    {
+        result |= SCROLLBAR_HORIZONTAL;
+    }
+    if (FullHeight(scrollpane) > scrollpane->h)
+    {
+        result |= SCROLLBAR_VERTICAL;
+    }
+
+    return result;
+}
+
+// If a scrollbar isn't needed, the scroll position is reset.
+
+static void SanityCheckScrollbars(txt_scrollpane_t *scrollpane)
+{
+    int scrollbars;
+    int max_x, max_y;
+
+    scrollbars = NeedsScrollbars(scrollpane);
+
+    if ((scrollbars & SCROLLBAR_HORIZONTAL) == 0)
+    {
+        scrollpane->x = 0;
+    }
+    if ((scrollbars & SCROLLBAR_VERTICAL) == 0)
+    {
+        scrollpane->y = 0;
+    }
+
+    max_x = FullWidth(scrollpane) - scrollpane->w;
+    max_y = FullHeight(scrollpane) - scrollpane->h;
+
+    if (scrollpane->x < 0)
+    {
+        scrollpane->x = 0;
+    }
+    else if (scrollpane->x > max_x)
+    {
+        scrollpane->x = max_x;
+    }
+
+    if (scrollpane->y < 0)
+    {
+        scrollpane->y = 0;
+    }
+    else if (scrollpane->y > max_y)
+    {
+        scrollpane->y = max_y;
+    }
+}
+
+static void TXT_ScrollPaneSizeCalc(TXT_UNCAST_ARG(scrollpane))
+{
+    TXT_CAST_ARG(txt_scrollpane_t, scrollpane);
+    int scrollbars;
+
+    if (scrollpane->child != NULL)
+    {
+        TXT_CalcWidgetSize(scrollpane->child);
+    }
+
+    // Expand as necessary (to ensure that no scrollbars are needed)?
+
+    if (scrollpane->expand_w)
+    {
+        scrollpane->w = FullWidth(scrollpane);
+    }
+    if (scrollpane->expand_h)
+    {
+        scrollpane->h = FullWidth(scrollpane);
+    }
+
+    scrollpane->widget.w = scrollpane->w;
+    scrollpane->widget.h = scrollpane->h;
+
+    // If we have scroll bars, we need to expand slightly to
+    // accomodate them. Eg. if we have a vertical scrollbar, we
+    // need to be an extra character wide.
+
+    scrollbars = NeedsScrollbars(scrollpane);
+
+    if (scrollbars & SCROLLBAR_HORIZONTAL)
+    {
+        ++scrollpane->widget.h;
+    }
+    if (scrollbars & SCROLLBAR_VERTICAL)
+    {
+        ++scrollpane->widget.w;
+    }
+}
+
+static void TXT_ScrollPaneDrawer(TXT_UNCAST_ARG(scrollpane), int selected)
+{
+    TXT_CAST_ARG(txt_scrollpane_t, scrollpane);
+    int x1, y1, x2, y2;
+    int scrollbars;
+
+    // We set a clipping area of the scroll pane.
+
+    x1 = scrollpane->widget.x,
+    y1 = scrollpane->widget.y,
+    x2 = x1 + scrollpane->w,
+    y2 = y1 + scrollpane->h;
+
+    scrollbars = NeedsScrollbars(scrollpane);
+
+    if (scrollbars & SCROLLBAR_HORIZONTAL)
+    {
+        TXT_DrawHorizScrollbar(x1,
+                               y1 + scrollpane->h,
+                               scrollpane->w,
+                               scrollpane->x,
+                               FullWidth(scrollpane) - scrollpane->w);
+    }
+
+    if (scrollbars & SCROLLBAR_VERTICAL)
+    {
+        TXT_DrawVertScrollbar(x1 + scrollpane->w,
+                              y1,
+                              scrollpane->h,
+                              scrollpane->y,
+                              FullHeight(scrollpane) - scrollpane->h);
+    }
+
+    TXT_PushClipArea(x1, x2, y1, y2);
+
+    // Draw the child widget
+
+    if (scrollpane->child != NULL)
+    {
+        TXT_DrawWidget(scrollpane->child, selected);
+    }
+
+    // Restore old clipping area.
+
+    TXT_PopClipArea();
+}
+
+static void TXT_ScrollPaneDestructor(TXT_UNCAST_ARG(scrollpane))
+{
+    TXT_CAST_ARG(txt_scrollpane_t, scrollpane);
+
+    if (scrollpane->child != NULL)
+    {
+        TXT_DestroyWidget(scrollpane->child);
+    }
+}
+
+static int TXT_ScrollPaneKeyPress(TXT_UNCAST_ARG(scrollpane), int key)
+{
+    TXT_CAST_ARG(txt_scrollpane_t, scrollpane);
+
+    if (scrollpane->child != NULL)
+    {
+        return TXT_WidgetKeyPress(scrollpane->child, key);
+    }
+    else
+    {
+        return 0;
+    }
+}
+
+static void TXT_ScrollPaneMousePress(TXT_UNCAST_ARG(scrollpane),
+                                     int x, int y, int b)
+{
+    TXT_CAST_ARG(txt_scrollpane_t, scrollpane);
+    int scrollbars;
+    int rel_x, rel_y;
+
+    scrollbars = NeedsScrollbars(scrollpane);
+
+    rel_x = x - scrollpane->widget.x;
+    rel_y = y - scrollpane->widget.y;
+
+    // Click on the horizontal scrollbar?
+    if ((scrollbars & SCROLLBAR_HORIZONTAL) && rel_y == scrollpane->h)
+    {
+        if (rel_x == 0)
+        {
+            --scrollpane->x;
+        }
+        else if (rel_x == scrollpane->w - 1)
+        {
+            ++scrollpane->x;
+        }
+
+        return;
+    }
+
+    // Click on the horizontal scrollbar?
+    if ((scrollbars & SCROLLBAR_VERTICAL) && rel_x == scrollpane->w)
+    {
+        if (rel_y == 0)
+        {
+            --scrollpane->y;
+        }
+        else if (rel_y == scrollpane->h - 1)
+        {
+            ++scrollpane->y;
+        }
+
+        return;
+    }
+
+    if (scrollpane->child != NULL)
+    {
+        TXT_WidgetMousePress(scrollpane->child,
+                             x - scrollpane->x,
+                             y - scrollpane->y,
+                             b);
+    }
+
+}
+
+static void TXT_ScrollPaneLayout(TXT_UNCAST_ARG(scrollpane))
+{
+    TXT_CAST_ARG(txt_scrollpane_t, scrollpane);
+
+    SanityCheckScrollbars(scrollpane);
+
+    // The child widget takes the same position as the scroll pane
+    // itself, but is offset by the scroll position.
+
+    if (scrollpane->child != NULL)
+    {
+        scrollpane->child->x = scrollpane->widget.x - scrollpane->x;
+        scrollpane->child->y = scrollpane->widget.y - scrollpane->y;
+    }
+}
+
+txt_widget_class_t txt_scrollpane_class =
+{
+    TXT_ScrollPaneSizeCalc,
+    TXT_ScrollPaneDrawer,
+    TXT_ScrollPaneKeyPress,
+    TXT_ScrollPaneDestructor,
+    TXT_ScrollPaneMousePress,
+    TXT_ScrollPaneLayout,
+};
+
+txt_scrollpane_t *TXT_NewScrollPane(int w, int h, TXT_UNCAST_ARG(target))
+{
+    TXT_CAST_ARG(txt_widget_t, target);
+    txt_scrollpane_t *scrollpane;
+
+    scrollpane = malloc(sizeof(txt_scrollpane_t));
+    TXT_InitWidget(scrollpane, &txt_scrollpane_class);
+    scrollpane->w = w;
+    scrollpane->h = h;
+    scrollpane->x = 0;
+    scrollpane->y = 0;
+    scrollpane->child = target;
+    scrollpane->expand_w = w <= 0;
+    scrollpane->expand_h = h <= 0;
+
+    return scrollpane;
+}
+
diff --git a/textscreen/txt_scrollpane.h b/textscreen/txt_scrollpane.h
new file mode 100644
index 00000000..661542a3
--- /dev/null
+++ b/textscreen/txt_scrollpane.h
@@ -0,0 +1,42 @@
+// Emacs style mode select   -*- C++ -*- 
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 2009 Simon Howard
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License
+// as published by the Free Software Foundation; either version 2
+// of the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+// 02111-1307, USA.
+//
+
+#ifndef TXT_SCROLLPANE_H
+#define TXT_SCROLLPANE_H
+
+typedef struct txt_scrollpane_s txt_scrollpane_t;
+
+#include "txt_widget.h"
+
+struct txt_scrollpane_s
+{
+    txt_widget_t widget;
+    int w, h;
+    int x, y;
+    int expand_w, expand_h;
+    txt_widget_t *child;
+};
+
+txt_scrollpane_t *TXT_NewScrollPane(int w, int h, TXT_UNCAST_ARG(target));
+
+#endif /* #ifndef TXT_SCROLLPANE_H */
+
+