From f42e079b708e2648a7b59736b3385c51dd4b3fd6 Mon Sep 17 00:00:00 2001
From: Nick Gasson <nick@nickg.me.uk>
Date: Sat, 24 Oct 2009 20:18:00 +0100
Subject: [PATCH] Use scissor test to crop widgets

---
 include/gui2/RenderContext.hpp |  4 ++++
 src/gui/Font.cpp               | 15 ++++++++++++-
 src/gui2/Button.cpp            |  5 +++--
 src/gui2/ContainerWidget.cpp   |  4 +++-
 src/gui2/RenderContext.cpp     | 41 ++++++++++++++++++++++++++++++----
 src/gui2/Theme.cpp             |  4 ++--
 6 files changed, 63 insertions(+), 10 deletions(-)

diff --git a/include/gui2/RenderContext.hpp b/include/gui2/RenderContext.hpp
index 47415c6..7343cf2 100644
--- a/include/gui2/RenderContext.hpp
+++ b/include/gui2/RenderContext.hpp
@@ -29,6 +29,8 @@
 
 namespace gui {
 
+   class Widget;
+
    class RenderContext {
    public:
       RenderContext();
@@ -37,6 +39,8 @@ namespace gui {
       void push_origin(int x, int y);
       void pop_origin();
 
+      void scissor(Widget* w);
+      
       void rectangle(int x, int y, int w, int h, Colour c);
       void border(int x, int y, int w, int h, Colour c);
 
diff --git a/src/gui/Font.cpp b/src/gui/Font.cpp
index 01a1c6e..35f9f9f 100644
--- a/src/gui/Font.cpp
+++ b/src/gui/Font.cpp
@@ -21,6 +21,7 @@
 #include <vector>
 #include <stdexcept>
 #include <cstdarg>
+#include <map>
 
 #include <GL/gl.h>
 #include "ft2build.h"
@@ -335,5 +336,17 @@ int Font::stringWidth(const char* fmt, ...) const
 
 IFontPtr gui::loadFont(const string& aFile, int aHeight, bool shadow)
 {
-   return IFontPtr(new Font(aFile, aHeight, shadow));
+   typedef tuple<string, int, bool> FontToken;
+   static map<FontToken, IFontPtr> cache;
+
+   FontToken t = make_tuple(aFile, aHeight, shadow);
+   map<FontToken, IFontPtr>::iterator it = cache.find(t);
+
+   if (it != cache.end())
+      return (*it).second;
+   else {
+      IFontPtr p(new Font(aFile, aHeight, shadow));
+      cache[t] = p;
+      return p;
+   }
 }
diff --git a/src/gui2/Button.cpp b/src/gui2/Button.cpp
index 4a195db..fbf2f17 100644
--- a/src/gui2/Button.cpp
+++ b/src/gui2/Button.cpp
@@ -29,9 +29,10 @@ void Button::render(RenderContext& rc) const
 {
    rc.rectangle(x(), y(), width(), height(),
       rc.theme().background());
-   rc.border(x(), y(), width(), height(),
-      rc.theme().border());
 
    rc.print(rc.theme().normal_font(), x() + 5, y() + 5,
       "Yahyahyah");
+
+   rc.border(x(), y(), width(), height(),
+      rc.theme().border());
 }
diff --git a/src/gui2/ContainerWidget.cpp b/src/gui2/ContainerWidget.cpp
index a32e34a..44a8484 100644
--- a/src/gui2/ContainerWidget.cpp
+++ b/src/gui2/ContainerWidget.cpp
@@ -28,8 +28,10 @@ ContainerWidget::ContainerWidget(const AttributeSet& attrs)
 void ContainerWidget::render(RenderContext& rc) const
 {
    for (ChildList::const_iterator it = const_begin();
-        it != const_end(); ++it)
+        it != const_end(); ++it) {
+      rc.scissor(*it);
       (*it)->render(rc);
+   }
 }
 
 void ContainerWidget::add_child(Widget* w)
diff --git a/src/gui2/RenderContext.cpp b/src/gui2/RenderContext.cpp
index 29a8a8e..c839ac3 100644
--- a/src/gui2/RenderContext.cpp
+++ b/src/gui2/RenderContext.cpp
@@ -16,11 +16,16 @@
 //
 
 #include "gui2/RenderContext.hpp"
+#include "gui2/Widget.hpp"
+#include "ILogger.hpp"
+#include "IWindow.hpp"
 
 #include <GL/gl.h>
 
 using namespace gui;
 
+IWindowPtr getGameWindow();
+
 namespace {
    inline void set_colour(Colour c)
    {
@@ -31,12 +36,13 @@ namespace {
 RenderContext::RenderContext()
    : origin_x(0), origin_y(0)
 {
-
+   glPushAttrib(GL_ENABLE_BIT);
+   glEnable(GL_SCISSOR_TEST);
 }
 
 RenderContext::~RenderContext()
 {
-
+   glPopAttrib();
 }
 
 void RenderContext::push_origin(int x, int y)
@@ -75,12 +81,26 @@ void RenderContext::border(int x, int y, int w, int h, Colour c)
 {
    offset(x, y);
    set_colour(c);
-   
-   glBegin(GL_LINE_LOOP);
+
+   x += 1;
+   y += 1;
+   w -= 1;
+   h -= 1;
+
+   glBegin(GL_LINES);
+
    glVertex2i(x, y);
    glVertex2i(x + w, y);
+   
+   glVertex2i(x + w, y);
+   glVertex2i(x + w, y + h);
+   
    glVertex2i(x + w, y + h);
    glVertex2i(x, y + h);
+   
+   glVertex2i(x, y + h);
+   glVertex2i(x, y - 1);
+   
    glEnd();
 }
 
@@ -89,3 +109,16 @@ void RenderContext::print(IFontPtr font, int x, int y, const string& s)
    offset(x, y);
    font->print(x, y, "%s", s.c_str());
 }
+
+void RenderContext::scissor(Widget* w)
+{
+   static int wh = getGameWindow()->height();
+   
+   int x = w->x() - 1;
+   int y = w->y() - 1;
+   offset(x, y);
+
+   y = wh - y - w->height() - 1;
+   
+   glScissor(x, y, w->width() + 1, w->height() + 1);
+}
diff --git a/src/gui2/Theme.cpp b/src/gui2/Theme.cpp
index 1cee39a..9cf7cb0 100644
--- a/src/gui2/Theme.cpp
+++ b/src/gui2/Theme.cpp
@@ -21,7 +21,7 @@ using namespace gui;
 
 Theme::Theme()
 {
-   normal_font_ = loadFont("data/fonts/Vera.ttf", 14);
+   normal_font_ = loadFont("data/fonts/Vera.ttf", 11, false);
 }
       
 Colour Theme::background() const
@@ -31,5 +31,5 @@ Colour Theme::background() const
 
 Colour Theme::border() const
 {
-   return make_colour(1.0f, 0.0f, 0.0f, 0.5f);
+   return make_colour(1.0f, 0.0f, 0.0f, 1.0f);
 }
-- 
2.39.2