IT'S ALIVE!

CMakeLists.txt

@@ -36,6 +36,7 @@ set(SRCS
   src/imgui-SFML.cpp
   src/filesys.cpp
   src/limgui.cpp
+  src/lua_buffers.cpp
   ${IMGUI}/imgui.cpp
   ${IMGUI}/imgui_draw.cpp
   ${IMGUI}/imgui_demo.cpp
@@ -48,6 +49,7 @@ set(HDRS
   src/limgui.h
   src/stb_image.h
   src/stb_image_write.h
+  src/lua_buffers.h
   ${LUA}/lua.hpp
   ${LUA}/lualib.h
 )

projects/circle.lua

@@ -1,11 +0,0 @@
-for i=1,10 do
-	print(i)
-end
-color={0,0,0,0}
-
-function update(  )
-	imgui.Begin("Hello")
-	local changed
-	changed,color=imgui.ColorEdit3("thing",color)
-	imgui.End()
-end

projects/spirograph.lua

@@ -0,0 +1,102 @@
+--[[ Example:
+imgui_config=make_config{
+	{"debug_display",false},
+	{"complexity",0.5,type="float"}, --implied min=0,max=1
+	{"shapes","3"},
+	{"w",3,type="int",min=1,max=5},
+}
+
+Begin
+End
+Bullet
+BulletText
+RadioButton
+CollapsingHeader
+SliderFloat
+SliderAngle
+SliderInt
+InputText
+]]
+function make_config(tbl,defaults)
+	local ret={}
+	defaults=defaults or {}
+	for i,v in ipairs(tbl) do
+		ret[v[1]]=defaults[v[1]] or v[2]
+		ret[i]=v
+	end
+	return ret
+end
+
+img_buf=img_buf or buffers.Make("color")
+tick=tick or 0
+config=make_config({
+	{"color",{0.5,0,0,1},type="color"},
+	{"k",0.2,type="float"},
+	{"l",0.4,type="float"},
+	{"R",400,type="int",min=0,max=512},
+	{"ticking",100,type="float",min=1,max=10000},
+},config)
+
+function draw_config( tbl )
+	for _,entry in ipairs(tbl) do
+		local name=entry[1]
+		local v=tbl[name]
+		local k=name
+		if type(v)=="boolean" then
+			if imgui.Button(k) then
+				tbl[k]=not tbl[k]
+			end
+		elseif type(v)=="string" then
+			local changing
+			changing,tbl[k]=imgui.InputText(k,tbl[k])
+			entry.changing=changing
+		else --if type(v)~="table" then
+
+			if entry.type=="int" then
+				local changing
+				changing,tbl[k]=imgui.SliderInt(k,tbl[k],entry.min or 0,entry.max or 100)
+				entry.changing=changing
+			elseif entry.type=="float" then
+				local changing
+				changing,tbl[k]=imgui.SliderFloat(k,tbl[k],entry.min or 0,entry.max or 1)
+				entry.changing=changing
+			elseif entry.type=="angle" then
+				local changing
+				changing,tbl[k]=imgui.SliderAngle(k,tbl[k],entry.min or 0,entry.max or 360)
+				entry.changing=changing
+			elseif entry.type=="color" then
+				local changing
+				changing,tbl[k]=imgui.ColorEdit4(k,tbl[k],true)
+				entry.changing=changing
+			end
+
+		end
+	end
+end
+function pos( t )
+	local k=config.k
+	local l=config.l
+	return config.R*((1-k)*math.cos(t)+l*k*math.cos(((1-k)/k)*t)),
+		   config.R*((1-k)*math.sin(t)-l*k*math.sin(((1-k)/k)*t))
+end
+function update(  )
+	imgui.Begin("Hello")
+
+	draw_config(config)
+	local c_u8={config.color[1]*255,config.color[2]*255,config.color[3]*255,config.color[4]*255}
+	if imgui.Button("Clear image") then
+		local s=STATE.size
+		for x=0,s[1]-1 do
+			for y=0,s[2]-1 do
+				img_buf:set(x,y,{0,0,0,0})
+			end
+		end
+	end
+	imgui.End()
+	for i=1,config.ticking do
+		local x,y=pos(tick/config.ticking);
+		img_buf:set(x+512,y+512,c_u8)
+		tick=tick+1
+	end
+	buffers.Present(img_buf)
+end

src/limgui.cpp

@@ -2,6 +2,10 @@
 
 #include <imgui.h>
 #include <vector>
+
+#include "lua.hpp"
+#include "lualib.h"
+#include "lauxlib.h"
 int lua_absindex(lua_State *L, int i) {
 	if (i < 0 && i > LUA_REGISTRYINDEX)
 		i += lua_gettop(L) + 1;

src/limgui.h

@@ -1,9 +1,6 @@
 #pragma once
 
-#include "lua.hpp"
-#include "lualib.h"
-#include "lauxlib.h"
-
+struct lua_State;
 int lua_open_imgui(lua_State* L);
-
+//NOTE: call this because on error, there might be unmatched imgui::begin/end(s)
 void fixup_imgui_state();

src/lua_buffers.cpp

@@ -0,0 +1,229 @@
+#include "lua_buffers.h"
+
+#include "SFML\Graphics.hpp"
+
+#include "lua.hpp"
+#include "lualib.h"
+#include "lauxlib.h"
+
+#include <unordered_map>
+enum class buffer_type {
+	vector_u8x4,
+	vector_float,
+};
+struct u8x4 {
+	uint8_t r, g, b, a;
+};
+struct buffer_entry
+{
+	int w;
+	buffer_type t;
+};
+std::unordered_map<void*, buffer_entry> buffer_registry;
+
+void get_current_size(lua_State* L, int& x, int& y)
+{
+	lua_getglobal(L, "STATE");
+	lua_getfield(L, -1, "size");
+
+	lua_rawgeti(L, -1, 1);
+	x=lua_tointeger(L, -1);
+	lua_pop(L, 1);
+
+	lua_rawgeti(L, -1, 2);
+	y = lua_tointeger(L, -1);
+	lua_pop(L, 1);
+
+	lua_pop(L, 2);
+}
+
+
+
+template <typename T>
+struct buffer_value_access{
+static constexpr char* name();
+static int push(lua_State* L, const T& v);
+static T to_element(lua_State* L, int id);
+static std::vector<T>* check(lua_State* L, int id) { return *reinterpret_cast<std::vector<T>**>(luaL_checkudata(L, id, name())); }
+static int get_buffer(lua_State* L)
+{
+	auto ptr = buffer_value_access<T>::check(L, 1);
+	int x = luaL_checkinteger(L, 2);
+	int y = luaL_checkinteger(L, 3);
+	auto e = buffer_registry[ptr];
+	auto& v = ptr->at(x*e.w + y); \
+	return buffer_value_access<T>::push(L, v);
+}
+static int set_buffer(lua_State* L) {
+	auto ptr = buffer_value_access<T>::check(L, 1);
+	int x = luaL_checkinteger(L, 2);
+	int y = luaL_checkinteger(L, 3);
+	auto new_value = buffer_value_access<T>::to_element(L, 4);
+	auto e = buffer_registry[ptr];
+	ptr->at(x*e.w + y) = new_value;
+	return 0;
+}
+static int del_buffer(lua_State* L) {	
+	auto ptr= check(L, 1);
+	buffer_registry.erase(ptr); delete ptr;
+	return 0;
+}
+static int len_buffer(lua_State* L) {
+	auto ptr = check(L, 1);
+	lua_pushnumber(L, ptr->size());
+	return 1;
+}
+static int index_buffer(lua_State* L) {
+	auto ptr = check(L, 1);
+	int id = luaL_checkinteger(L, 2);
+	auto& v = ptr->at(id);
+	return push(L, v);
+}
+static int newindex_buffer(lua_State* L){
+	auto ptr = check(L, 1);
+	int id = luaL_checkinteger(L, 2);
+	auto new_value = to_element(L, 3);
+	ptr->at(id) = new_value;
+	return 0;
+}
+static void resize_buffer(void* d, int w, int h){
+	auto p = reinterpret_cast<std::vector<T>*>(d);
+	p->resize(w*h);
+	buffer_registry[d].w = w;
+}
+static int make_buffer(lua_State* L, int w, int h){
+	auto ret = new std::vector<T>(w*h);
+	buffer_registry[ret].w = w;
+	auto np=lua_newuserdata(L,sizeof(ret));
+	*reinterpret_cast<std::vector<T>**>(np)=ret;
+	if (luaL_newmetatable(L, name()))
+	{
+		lua_pushcfunction(L, del_buffer);
+		lua_setfield(L, -2, "__gc");
+		lua_pushcfunction(L, len_buffer);
+		lua_setfield(L, -2, "__len");
+
+		lua_pushcfunction(L, get_buffer);
+		lua_setfield(L, -2, "get");
+		lua_pushcfunction(L, set_buffer);
+		lua_setfield(L, -2, "set");
+		lua_pushvalue(L, -1);
+		lua_setfield(L, -2, "__index");
+	}
+	lua_setmetatable(L, -2);
+	return 1;
+}
+};
+
+static int make_lua_auto_buffer(lua_State* L)
+{
+	const char* buf_type = luaL_checkstring(L, 1);
+	int x, y;
+	get_current_size(L, x, y);
+
+	if (strcmp(buf_type, "color")==0)
+	{
+		return buffer_value_access<u8x4>::make_buffer(L,x,y);
+	} else if (strcmp(buf_type, "float") == 0)
+	{
+		return buffer_value_access<float>::make_buffer(L, x, y);
+	}
+}
+static int present_buffer(lua_State* L)
+{
+	auto ptr= buffer_value_access<u8x4>::check(L, 1);
+	lua_getglobal(L, "STATE");
+	lua_getfield(L, -1, "texture");
+
+	auto tex=reinterpret_cast<sf::Texture*>(lua_touserdata(L, -1));
+	lua_pop(L, 2);
+	tex->update(reinterpret_cast<const sf::Uint8*>(ptr->data()));
+	return 0;
+}
+static const luaL_Reg lua_buffers_lib[] = {
+	{ "Make",make_lua_auto_buffer },
+	{ "Present",present_buffer},
+	{ NULL, NULL }
+};
+
+int lua_open_buffers(lua_State * L)
+{
+	luaL_newlib(L, lua_buffers_lib);
+
+	lua_setglobal(L, "buffers");
+
+	return 1;
+}
+
+void resize_lua_buffers(int w, int h)
+{
+	for (auto& v : buffer_registry)
+	{
+		switch (v.second.t)
+		{
+#define DO_BUFFER_RESIZE(tname,name) case buffer_type::vector_##tname: buffer_value_access<tname>::resize_buffer(v.first,w,h);break
+		DO_BUFFER_RESIZE(u8x4, color);
+		DO_BUFFER_RESIZE(float, float);
+		default:
+			break;
+		}
+	}
+}
+#undef DO_BUFFER_RESIZE
+
+template<>
+static constexpr char * buffer_value_access<u8x4>::name()
+{
+	return "color_buffer";
+}
+
+template<>
+static int buffer_value_access<u8x4>::push(lua_State * L, const u8x4& v)
+{
+	lua_newtable(L);
+
+	lua_pushinteger(L, v.r);
+	lua_rawseti(L, -2, 1);
+
+	lua_pushinteger(L, v.g);
+	lua_rawseti(L, -2, 2);
+
+	lua_pushinteger(L, v.b);
+	lua_rawseti(L, -2, 3);
+
+	lua_pushinteger(L, v.a);
+	lua_rawseti(L, -2, 4);
+
+	return 1;
+}
+
+template<>
+static u8x4 buffer_value_access<u8x4>::to_element(lua_State * L, int id)
+{
+	u8x4 ret;
+	luaL_checktype(L, id, LUA_TTABLE);
+	lua_rawgeti(L, id, 1); ret.r = lua_tointeger(L, -1); lua_pop(L, 1);
+	lua_rawgeti(L, id, 2); ret.g = lua_tointeger(L, -1); lua_pop(L, 1);
+	lua_rawgeti(L, id, 3); ret.b = lua_tointeger(L, -1); lua_pop(L, 1);
+	lua_rawgeti(L, id, 4); ret.a = lua_tointeger(L, -1); lua_pop(L, 1);
+	return ret;
+}
+
+template<>
+static constexpr char * buffer_value_access<float>::name()
+{
+	return "float_buffer";
+}
+
+template<>
+static int buffer_value_access<float>::push(lua_State * L, const float& v)
+{
+	lua_pushnumber(L, v);
+	return 1;
+}
+
+template<>
+static float buffer_value_access<float>::to_element(lua_State * L, int id)
+{
+	return luaL_checknumber(L, id);
+}

src/lua_buffers.h

@@ -0,0 +1,6 @@
+#pragma once
+
+struct lua_State;
+int lua_open_buffers(lua_State* L);
+
+void resize_lua_buffers(int w,int h);