1/*
2 * Copyright 2013 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#include "SampleCode.h"
9#include "SkView.h"
10#include "SkLua.h"
11#include "SkCanvas.h"
12
13extern "C" {
14#include "lua.h"
15#include "lualib.h"
16#include "lauxlib.h"
17}
18
19static const char gDrawName[] = "onDrawContent";
20
21static const char gCode[] = ""
22    "require \"math\" "
23    ""
24    "local r = { left = 10, top = 10, right = 100, bottom = 80 } "
25    "local x = 0;"
26    ""
27    "local paint = Sk.newPaint();"
28    "paint:setAntiAlias(true);"
29    ""
30    "local image = Sk.loadImage('/skia/trunk/sailboat.jpg');"
31    ""
32    "local color = {a = 1, r = 1, g = 0, b = 0};"
33    ""
34    "function rnd(range) "
35    "   return math.random() * range;"
36    "end "
37    ""
38    "rndX = function () return rnd(640) end "
39    "rndY = function () return rnd(480) end "
40    ""
41    "function draw_rand_path(canvas);"
42    "   if not path_paint then "
43    "       path_paint = Sk.newPaint();"
44    "       path_paint:setAntiAlias(true);"
45    "   end "
46    "   path_paint:setColor({a = 1, r = math.random(), g = math.random(), b = math.random() });"
47    ""
48    "   local path = Sk.newPath();"
49    "   path:moveTo(rndX(), rndY());"
50    "   for i = 0, 50 do "
51    "       path:quadTo(rndX(), rndY(), rndX(), rndY());"
52    "   end "
53    "   canvas:drawPath(path, path_paint);"
54    ""
55    "   paint:setColor{a=1,r=0,g=0,b=1};"
56    "   local align = { 'left', 'center', 'right' };"
57    "   paint:setTextSize(30);"
58    "   for k, v in next, align do "
59    "       paint:setTextAlign(v);"
60    "       canvas:drawText('Hamburgefons', 320, 200 + 30*k, paint);"
61    "   end "
62    "end "
63    ""
64    "function onStartup() "
65    "   local paint = Sk.newPaint();"
66    "   paint:setColor{a=1, r=1, g=0, b=0};"
67    "   local doc = Sk.newDocumentPDF('/skia/trunk/test.pdf');"
68    "   local canvas = doc:beginPage(72*8.5, 72*11);"
69    "   canvas:drawText('Hello Lua', 300, 300, paint);"
70    "   doc:close();"
71    "   doc = nil;"
72    "end "
73    ""
74    "function onDrawContent(canvas) "
75    "   draw_rand_path(canvas);"
76    "   color.g = x / 100;"
77    "   paint:setColor(color) "
78    "   canvas:translate(x, 0);"
79    "   canvas:drawOval(r, paint) "
80    "   x = x + 1;"
81    "   canvas:drawImage(image, x, r.bottom + 50, 0.5);"
82    "   if x > 100 then x = 0 end;"
83    "end "
84    ""
85    "onStartup();";
86
87class LuaView : public SampleView {
88public:
89    LuaView() : fLua(NULL) {}
90
91    virtual ~LuaView() {
92        SkDELETE(fLua);
93    }
94
95    lua_State* ensureLua() {
96        if (NULL == fLua) {
97            fLua = SkNEW(SkLua);
98            fLua->runCode(gCode);
99        }
100        return fLua->get();
101    }
102
103protected:
104    virtual bool onQuery(SkEvent* evt) SK_OVERRIDE {
105        if (SampleCode::TitleQ(*evt)) {
106            SampleCode::TitleR(evt, "Lua");
107            return true;
108        }
109        SkUnichar uni;
110        if (SampleCode::CharQ(*evt, &uni)) {
111        }
112        return this->INHERITED::onQuery(evt);
113    }
114
115    virtual void onDrawContent(SkCanvas* canvas) SK_OVERRIDE {
116        lua_State* L = this->ensureLua();
117
118        lua_getglobal(L, gDrawName);
119        if (!lua_isfunction(L, -1)) {
120            int t = lua_type(L, -1);
121            SkDebugf("--- expected %s function %d, ignoring.\n", gDrawName, t);
122            lua_pop(L, 1);
123        } else {
124            // does it make sense to try to "cache" the lua version of this
125            // canvas between draws?
126            fLua->pushCanvas(canvas);
127            if (lua_pcall(L, 1, 0, 0) != LUA_OK) {
128                SkDebugf("lua err: %s\n", lua_tostring(L, -1));
129            }
130        }
131        // need a way for the lua-sample to tell us if they want animations...
132        // hard-code it ON for now.
133        this->inval(NULL);
134    }
135
136    virtual SkView::Click* onFindClickHandler(SkScalar x, SkScalar y,
137                                              unsigned modi) SK_OVERRIDE {
138        return this->INHERITED::onFindClickHandler(x, y, modi);
139    }
140
141    virtual bool onClick(Click* click) SK_OVERRIDE {
142        return this->INHERITED::onClick(click);
143    }
144
145private:
146    SkLua* fLua;
147
148    typedef SampleView INHERITED;
149};
150
151//////////////////////////////////////////////////////////////////////////////
152
153static SkView* MyFactory() { return new LuaView; }
154static SkViewRegister reg(MyFactory);
155