Lua calling `GetLightmapPageSize`

[Akabenko]

Description

Functions ITexture:GetMappingWidth, ITexture:Width, ITexture:GetMappingHeight, ITexture:Height can't get a lightmaps size. Therefore, I propose to add a function GetLightmapPageSize. This will simplify manual work with lightmaps.

if (!IsErrorTexture(g_pMaterialSystem->FindTexture("[lightmap0]", ""))) // Boundaries check
{
	int nLightmapWidth;
	int nLightmapHeight;
	g_pMaterialSystem->GetLightmapPageSize(0, &nLightmapWidth, &nLightmapHeight);

	ConMsg("nLightmapWidth: %d; nLightmapHeight: %d\n", nLightmapWidth, nLightmapHeight);
}
-- thanks mutezero

Other methods (invalid):

ITexture* m_pLightmapTexture = materials->FindTexture("[lightmap0]", TEXTURE_GROUP_LIGHTMAP);
        
if (m_pLightmapTexture) {
    int nLightmapWidth = m_pLightmapTexture->GetActualWidth();
    int nLightmapHeight = m_pLightmapTexture->GetActualHeight();
    ConMsg("GetActualWidth: %d; GetActualHeight: %d\n", nLightmapWidth, nLightmapHeight);

    int nLightmapWidth2 = m_pLightmapTexture->GetMappingWidth();
    int nLightmapHeight2 = m_pLightmapTexture->GetMappingHeight();
    ConMsg("GetMappingWidth: %d; GetMappingHeight: %d\n", nLightmapWidth2, nLightmapHeight2);
}

Alternatively:

pShaderAPI->GetLightmapDimensions(&nLightmapWidth, &nLightmapHeight);

[Akabenko]

Test code for lightmap getting, but here size info is invalid.

local prefix = "[lightmap %d]"

local fail = false
local iLightMapNum = 0
local plm = {}
local m_pLightmapPages = {}

local maxWidth = 0
local maxHeight = 0

local name_to_tex = {}

local function GetLightmaps()
	return plm
end

local function GetMaxLightmapPageWidth()
	if maxWidth == 1 then return 512 end
	return maxWidth
end

local function GetMaxLightmapPageHeight()
	if maxHeight == 1 then return 256 end
	return maxHeight
end

local function GetLightmapWidth( lightmapPageID )
	if maxWidth == 1 then return 512 end
	return m_pLightmapPages[lightmapPageID].width
end

local function GetLightmapHeight( lightmapPageID )
	if maxHeight == 1 then return 256 end
	return m_pLightmapPages[lightmapPageID].height
end

local function StoreLightMapInfo()
	while !fail do
		local tex_name = string.format(prefix, iLightMapNum)
		local mat = CreateMaterial(tex_name, "UnlitGeneric",{})
		mat:SetTexture("$basetexture", tex_name)
		local tex = mat:GetTexture("$basetexture")

		if !tex or tex:IsErrorTexture() then
			fail = true
			iLightMapNum = iLightMapNum - 1
		else
			plm[iLightMapNum] = tex

			-- invalid width and height
			local width = math.max( mat:Width(), math.max( tex:Width(), tex:GetMappingWidth() ) )
			local height = math.max( mat:Height(), math.max( tex:Height(), tex:GetMappingHeight() ))
			if width > maxWidth then maxWidth = width end
			if height > maxHeight then maxHeight = height end

			m_pLightmapPages[iLightMapNum] = {
				width = width;
				height = height;
			}
		end

		if !fail then
			iLightMapNum = iLightMapNum + 1
		end
	end

	for i = 0, #GetLightmaps() do
		name_to_tex[string.format(prefix, i)] = GetLightmaps()[i]
	end
end

StoreLightMapInfo()
PrintTable(GetLightmaps())

Result, gm_construct:

[0]	=	Texture [[lightmap 0]]
[1]	=	Texture [[lightmap 1]]
[2]	=	Texture [[lightmap 2]]
[3]	=	Texture [[lightmap 3]]
[4]	=	Texture [[lightmap 4]]
[5]	=	Texture [[lightmap 5]]
[6]	=	Texture [[lightmap 6]]
[7]	=	Texture [[lightmap 7]]
[8]	=	Texture [[lightmap 8]]
[9]	=	Texture [[lightmap 9]]
[10]	=	Texture [[lightmap 10]]
[11]	=	Texture [[lightmap 11]]
[12]	=	Texture [[lightmap 12]]
[13]	=	Texture [[lightmap 13]]
[14]	=	Texture [[lightmap 14]]
[15]	=	Texture [[lightmap 15]]
[16]	=	Texture [[lightmap 16]]
[17]	=	Texture [[lightmap 17]]
[18]	=	Texture [[lightmap 18]]