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Mail Archives: djgpp/1999/08/26/04:26:27

Message-Id: <199908260412.AAA09411@delorie.com>
From: "Dan Gold" <TedMat AT CoastNet DOT com>
To: <djgpp AT delorie DOT com>
Subject: Struct Array Allocation, Line Pointers, Automatic Offseting?
Date: Wed, 25 Aug 1999 23:55:08 -0700
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Reply-To: djgpp AT delorie DOT com

I made an 1 dimensional array of a struct and made line pointers to the
start of each row to make it like a 2 dimensional array.  If I want to
reference the line pointer as ->line[4][5], it will start on the row index
4, but will the 5 jump 5 tiles structs ahead as I allocated or just bytes. 
This is simalar to Allegro's bitmap line pointers which jump ahead bytes,
but I am using structures not bytes.

If it does jump ahead structs for me, is there any speed concern when
multiplying the address location 5 times by the size of the struct? [4th
row] + [5 * sizeof TILE] 

One more thing.  Does a struct pointer equal one 32bit address or an
address for each member of the struct?

((--Thanks From Dan Gold--))

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