Ticket #8419: credits.diff

TODO

@@ -196 +196 @@
 * Maybe add the ScummVM logo (+typeface?) to the about dialog
 * Unify DirBrowserDialog and FileBrowserDialog.
 * MacOS X version of FileBrowserDialog, since there is one of DirBrowserDialog.
-* The credits scroll is too CPU intensive. This is because for each time the
-  text is redrawn it has to do a full redraw, which causes blendRect() to be
-  called twice. Perhaps AboutDialog could keep a private copy of the blended
-  background so that it wouldn't have to be re-generated each time? Of course
-  we'd probably have to take screen changes into account, but there already is
-  a mechanism for that, I believe.
 
 Launcher
 ========

gui/about.cpp

@@ -120 +120 @@
         _scrollPos = 0;
         _modifiers = 0;
         _willClose = false;
+        _canvas.pixels = NULL;
 
         Dialog::open();
 }
 
+void AboutDialog::close() {
+        free(_canvas.pixels);
+        Dialog::close();
+}
+
 void AboutDialog::drawDialog() {
-        // Blend over the background
-        g_gui.blendRect(_x, _y, _w, _h, g_gui._bgcolor);
+        if (!_canvas.pixels) {
+                // Blend over the background. Since we can't afford to do that
+                // every time the text is updated (it's horribly CPU intensive)
+                // we do it just once and then use a copy of the result as our
+                // static background for the remainder of the credits.
+                g_gui.blendRect(_x, _y, _w, _h, g_gui._bgcolor);
+                g_gui.getRect(&_canvas, _x, _y, _w, _h);
+        }
+
+        g_gui.putRect(&_canvas, _x, _y);
 
         // Draw text
         // TODO: Add a "fade" effect for the top/bottom text lines
@@ -212 +226 @@
                 } else if ((uint32)_scrollPos > _lines.size() * _lineHeight) {
                         _scrollPos = 0;
                         _scrollTime += kScrollStartDelay;
-                } else {
-                        g_gui.addDirtyRect(_x, _y, _w, _h);
                 }
-                draw(); // Issue a full redraw
+                drawDialog();
         }
 }
 
+void AboutDialog::handleScreenChanged() {
+        // The screen has changed. Do a full redraw to ensure that the canvas
+        // we draw the text on will still have the correct background image.
+        free(_canvas.pixels);
+        _canvas.pixels = NULL;
+        draw();
+}
+
 void AboutDialog::handleMouseUp(int x, int y, int button, int clickCount) {
         // Close upon any mouse click
         close();

gui/about.h

@@ -23 +23 @@
 
 #include "gui/dialog.h"
 #include "common/str.h"
+#include "graphics/surface.h"
 
 namespace GUI {
 
@@ -35 +36 @@
         uint32          _lineHeight;
         byte            _modifiers;
         bool            _willClose;
+        Graphics::Surface       _canvas;
 
 public:
         AboutDialog();
 
         void open();
+        void close();
         void drawDialog();
         void handleTickle();
+        void handleScreenChanged();
         void handleMouseUp(int x, int y, int button, int clickCount);
         void handleKeyDown(uint16 ascii, int keycode, int modifiers);
         void handleKeyUp(uint16 ascii, int keycode, int modifiers);

gui/newgui.cpp

@@ -301 +301 @@
         _screen.vLine(x * _scaleFactor, y * _scaleFactor, y2 * _scaleFactor, color);
 }
 
+void NewGui::getRect(Graphics::Surface *s, int x, int y, int w, int h) {
+        Common::Rect rect(x * _scaleFactor, y * _scaleFactor, (x + w) * _scaleFactor, (y + h) * _scaleFactor);
+        rect.clip(_screen.w, _screen.h);
+
+        if (!rect.isValidRect())
+                return;
+
+        s->w = rect.width();
+        s->h = rect.height();
+        s->bytesPerPixel = sizeof(OverlayColor);
+        s->pitch = s->w * s->bytesPerPixel;
+        s->pixels = (OverlayColor *)malloc(s->pitch * s->h);
+
+        w = s->w;
+        h = s->h;
+
+        OverlayColor *dst = (OverlayColor *)s->pixels;
+        OverlayColor *src = getBasePtr(rect.left, rect.top);
+
+        while (h--) {
+                memcpy(dst, src, s->pitch);
+                src += _screenPitch;
+                dst += s->w;
+        }
+}
+
+void NewGui::putRect(Graphics::Surface *s, int x, int y) {
+        Common::Rect rect(x * _scaleFactor, y * _scaleFactor, x * _scaleFactor + s->w, y * _scaleFactor + s->h);
+        rect.clip(_screen.w, _screen.h);
+
+        if (!rect.isValidRect())
+                return;
+
+        OverlayColor *src = (OverlayColor *)s->pixels;
+        OverlayColor *dst = getBasePtr(rect.left, rect.top);
+
+        int w = rect.width();
+        int h = rect.height();
+
+        while (h--) {
+                memcpy(dst, src, s->pitch);
+                src += w;
+                dst += _screenPitch;
+        }
+}
+
 void NewGui::blendRect(int x, int y, int w, int h, OverlayColor color, int level) {
 #ifdef NEWGUI_256
         fillRect(x, y, w, h, color);

gui/newgui.h

@@ -134 +134 @@
         void box(int x, int y, int width, int height, OverlayColor colorA, OverlayColor colorB);
         void hLine(int x, int y, int x2, OverlayColor color);
         void vLine(int x, int y, int y2, OverlayColor color);
+        void getRect(Graphics::Surface *s, int x, int y, int w, int h);
+        void putRect(Graphics::Surface *s, int x, int y);
         void blendRect(int x, int y, int w, int h, OverlayColor color, int level = 3);
         void fillRect(int x, int y, int w, int h, OverlayColor color);
         void frameRect(int x, int y, int w, int h, OverlayColor color);