ref: 18b85275bb4a995fbfcc7924ac488ba8df35de4a
parent: 47d9aa4bee9831d6f68773921817639f2c015885
author: telephil9 <telephil9@gmail.com>
date: Wed Oct 21 17:06:17 EDT 2020
Added helper functions to simplify API implementation Inspired by lua C API, some new helper functions were added to retrieve libdraw objects from the stack. These helpers simplify a lot the implementation of individual libdraw functions exported to lua. Sample program was also cleaned up and a call to the newly added line() function included.
--- a/lua9.c
+++ b/lua9.c
@@ -124,6 +124,20 @@
return p;
}
+static Point l_checkpoint(lua_State *L, int index)
+{+ if(lua_istable(L, index) == 0)
+ luaL_argerror(L, index, "draw: point table expected");
+ return l_getpoint(L, index);
+}
+
+static Point l_optpoint(lua_State *L, int index)
+{+ if(lua_istable(L, index) == 0)
+ return ZP;
+ return l_getpoint(L, index);
+}
+
static Rectangle l_getrect(lua_State *L, int index)
{Rectangle r;
@@ -150,67 +164,82 @@
return r;
}
-static int l_draw(lua_State *L) {+static Rectangle l_checkrect(lua_State *L, int index)
+{+ if(lua_istable(L, index) == 0)
+ luaL_argerror(L, index, "draw: rectangle table expected");
+ return l_getrect(L, index);
+}
+
+static Image* l_checkimage(lua_State *L, int index)
+{ImagePtr *p;
+
+ p = (ImagePtr*)luaL_checkudata(L, index, IMAGE_META);
+ luaL_argcheck(L, p != NULL, index, "draw: Image expected");
+ return p->p;
+}
+
+static Image* l_optimage(lua_State *L, int index)
+{+ if(lua_isnil(L, index))
+ return nil;
+ return l_checkimage(L, index);
+}
+
+static Font* l_checkfont(lua_State *L, int index)
+{+ FontPtr *p;
+
+ p = (FontPtr*)luaL_checkudata(L, index, FONT_META);
+ luaL_argcheck(L, p != NULL, index, "draw: Font expected");
+ return p->p;
+}
+
+static int l_draw(lua_State *L) {Image *dst, *src, *mask;
- Point pt;
+ Point p;
Rectangle r;
-
- p = (ImagePtr*)luaL_checkudata(L, 1, IMAGE_META);
- luaL_argcheck(L, p != NULL, 1, "draw: Image expected");
- dst = p->p;
- if(lua_istable(L, 2) == 0) {- luaL_argerror(L, 2, "draw: table expected");
- } else {- r = l_getrect(L, 2);
- }
- p = (ImagePtr*)luaL_checkudata(L, 3, IMAGE_META);
- luaL_argcheck(L, p != NULL, 3, "draw: Image expected");
- src = p->p;
- mask = nil;
- if(lua_isnil(L, 4) == 0) {- p = (ImagePtr*)luaL_checkudata(L, 4, IMAGE_META);
- luaL_argcheck(L, p != NULL, 4, "draw: Image expected");
- mask = p->p;
- }
- if(lua_istable(L, 5) == 0) {- luaL_argerror(L, 2, "draw: table expected");
- } else {- pt = l_getpoint(L, 5);
- }
- draw(dst, r, src, mask, pt);
+
+ dst = l_checkimage(L, 1);
+ r = l_checkrect(L, 2);
+ src = l_checkimage(L, 3);
+ mask = l_optimage(L, 4);
+ p = l_checkpoint(L, 5);
+ draw(dst, r, src, mask, p);
return 0;
}
+static int l_line(lua_State *L) {+ Image *dst, *src;
+ Point p0, p1, sp;
+ int end0, end1, thick;
+
+ dst = l_checkimage(L, 1);
+ p0 = l_checkpoint(L, 2);
+ p1 = l_checkpoint(L, 3);
+ end0 = luaL_checkinteger(L, 4);
+ end1 = luaL_checkinteger(L, 5);
+ thick = luaL_checkinteger(L, 6);
+ src = l_checkimage(L, 7);
+ sp = l_checkpoint(L, 8);
+ line(dst, p0, p1, end0, end1, thick, src, sp);
+ return 0;
+}
+
static int l_string(lua_State *L) {- ImagePtr *p;
- FontPtr *fp;
Image *dst, *src;
Font *f;
- Point pt, spt;
+ Point p, sp;
const char *s;
- p = (ImagePtr*)luaL_checkudata(L, 1, IMAGE_META);
- luaL_argcheck(L, p != NULL, 1, "draw: Image expected");
- dst = p->p;
- if(lua_istable(L, 2)) {- pt = l_getpoint(L, 2);
- } else {- luaL_argerror(L, 2, "draw: table expected");
- }
- p = (ImagePtr*)luaL_checkudata(L, 3, IMAGE_META);
- luaL_argcheck(L, p != NULL, 3, "draw: Image expected");
- src = p->p;
- if(lua_istable(L, 4)) {- spt = l_getpoint(L, 4);
- } else {- spt = ZP;
- }
- fp = (FontPtr*)luaL_checkudata(L, 5, FONT_META);
- luaL_argcheck(L, fp != NULL, 5, "draw: Font expected");
- f = fp->p;
- s = luaL_checkstring(L, 6);
- string(dst, pt, src, spt, f, s);
+ dst = l_checkimage(L, 1);
+ p = l_checkpoint(L, 2);
+ src = l_checkimage(L, 3);
+ sp = l_optpoint(L, 4);
+ f = l_checkfont(L, 5);
+ s = luaL_checkstring(L, 6);
+ string(dst, p, src, sp, f, s);
return 0;
}
@@ -358,10 +387,17 @@
{ "einit", l_einit }, { "event", l_event }, { "draw", l_draw },+ { "line", l_line }, { "string", l_string }, { NULL, NULL }};
+static void l_pushglobal(lua_State *L, const char *name, int value, int index)
+{+ lua_pushnumber(L, value);
+ lua_setfield(L, index, name);
+}
+
int luaopen_drawlib (lua_State *L) {create_metatable(L, IMAGE_META, image_funcs);
create_metatable(L, DISPLAY_META, display_funcs);
@@ -371,6 +407,11 @@
lua_setfield(L, -2, "Emouse");
lua_pushnumber(L, Ekeyboard);
lua_setfield(L, -2, "Ekeyboard");
+ l_pushglobal(L, "Endsquare", Endsquare, -2);
+ l_pushglobal(L, "Enddisc", Enddisc, -2);
+ l_pushglobal(L, "Endarrow", Endarrow, -2);
+ l_pushglobal(L, "Endmask", Endmask, -2);
+
return 1;
}
--- a/sample.lua
+++ b/sample.lua
@@ -1,20 +1,22 @@
-#!/bin/ape/lua
+#!/bin/ape/lua9
-- lua libdraw sample
function rect(x0, y0, x1, y1)
- r = { min={}, max={} }- r.min.x = x0
- r.min.y = y0
- r.max.x = x1
- r.max.y = y1
- return r
+ return { min = { x = x0, y = y0 }, max = { x = x1, y = y1 } }end
+function pt(x, y)
+ return { x = x, y = y }+end
+
+local ZP = pt(0, 0)
+
function eresized()
- draw.draw(screen, screen.r, display.white, nil, {x=0, y=0})- draw.draw(screen, rect(50, 150, 100, 200), display.black, nil, {x=0, y=0})- draw.string(screen, {x=110, y=160}, display.black, nil, font, 'Hello LUA')+ draw.draw(screen, screen.r, display.white, nil, ZP)
+ draw.draw(screen, rect(50, 150, 100, 200), display.black, nil, ZP)
+ draw.string(screen, pt(110, 160), display.black, nil, font, 'Hello LUA')
+ draw.line(screen, pt(50, 210), pt(200, 210), draw.Endsquare, draw.Endarrow, 1, display.black, ZP)
end
draw.initdraw('lua sample')