Fallacies of Doom - RivieraDEV 19

Lessons learned from porting Doom 3 to Java

@blackbeard0x14e @blackbeard0x14e Boring intro: history • id Software: Unusual company
creating ‘innovative’ games ◦ (Rover, Dave, Keen, Wolf3D, Doom, Quake...etc • Self taught era, eﬃcient coding style(s) ◦ Nerd rage anecdote • Djoom3==fun • So why the boring awesome intro?

@blackbeard0x14e

@blackbeard0x14e wishlist “ C++ protects against accident, not against fraud.
” Bjarne Stroustrup

@blackbeard0x14e

@blackbeard0x14e @blackbeard0x14e Operator overloading cout << ”Total price: “ <<
price*quantity << endl; p2 = anchor + 32.0f * coneVector - master->GetWorldOrigin(); p2 = anchor.oPlus(coneVector.oMultiply(32.0f).oMinus(master.GetWorldOrigin())); p2 = anchor.oPlus(coneVector.oMultiply(32.0f)).oMinus(master.GetWorldOrigin()); [2] https://www.cs.virginia.edu/~evans/cs655/readings/steele.pdf

@blackbeard0x14e @blackbeard0x14e Operator overloading idMat3 a, b, c, z; z
= a + b * c; z = a.oPlus(b).oMultiply(c); z = b.oMultiply(c).oPlus(a);//technically correct

@blackbeard0x14e >>>

@blackbeard0x14e @blackbeard0x14e Unsigned primitives Runtime or compile-time error??

@blackbeard0x14e @blackbeard0x14e Unsigned primitives

@blackbeard0x14e @blackbeard0x14e Unsigned primitives Microbenchmark alert:

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@blackbeard0x14e @blackbeard0x14e Immutability; const vs ﬁnal

@blackbeard0x14e @blackbeard0x14e sizeof( )

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@blackbeard0x14e @blackbeard0x14e Enum

@blackbeard0x14e @blackbeard0x14e Super.super...inheritance?

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@blackbeard0x14e @blackbeard0x14e Pointers

@blackbeard0x14e (thank God we don’t have this…)-list System.out.println( (byte)~(char)-(int)+(long)-1 );

@blackbeard0x14e @blackbeard0x14e Death by Macros [3] https://blogs.msdn.microsoft.com/oldnewthing/20050106-00/?p=36783 [4] https://youtu.be/4cCeUfzH-No?t=23m

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@blackbeard0x14e @blackbeard0x14e Death by Macros

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@blackbeard0x14e @blackbeard0x14e Hungarian Camels [5]https://www.joelonsoftware.com/2005/05/11/making-wrong-code-look-wrong/ [6] https://steve-yegge.blogspot.nl/2006/03/execution-in-kingdom-of-nouns.html

@blackbeard0x14e Hungarian Camels

@blackbeard0x14e @blackbeard0x14e Unholy union

@blackbeard0x14e @blackbeard0x14e Unholy union: SDL_events.h

@blackbeard0x14e Unholy union

@blackbeard0x14e @blackbeard0x14e Unholy union

@blackbeard0x14e nice to have -list “ Object-oriented design is the
roman numerals of Computing. ” Rob Pike

@blackbeard0x14e

@blackbeard0x14e @blackbeard0x14e Destructor • Deconstructors • Finalize(@deprecated) • Autocloseable++

@blackbeard0x14e Default arguments

@blackbeard0x14e @blackbeard0x14e string::insert, string::swap

@blackbeard0x14e @blackbeard0x14e Inlining

@blackbeard0x14e weird(tips...tricks...pitfalls) -list Integer a = 42; Integer b =
42; System.out.println(a == b); Integer c = 666; Integer d = 666; System.out.println(c == d); String e = “666”; String f = “666”; String g = new String(“666”); System.out.println(e == f); System.out.println(f == g);

@blackbeard0x14e @blackbeard0x14e The memory watcher

@blackbeard0x14e @blackbeard0x14e 5.1.2. Widening Primitive Conversion(...aka read the JLS!)

@blackbeard0x14e @blackbeard0x14e Pop goes the callstack

@blackbeard0x14e @blackbeard0x14e Floating point operator precedence

@blackbeard0x14e

@blackbeard0x14e @blackbeard0x14e Floating point operator precedence

@blackbeard0x14e @blackbeard0x14e Conditional breakpoints

@blackbeard0x14e @blackbeard0x14e Conditional breakpoints •Sloooow(interpretive) Microbenchmark alert:

@blackbeard0x14e @blackbeard0x14e A backwards compatible story?

@blackbeard0x14e @blackbeard0x14e Sometimes the bug isn’t in your code...T_T

@blackbeard0x14e @blackbeard0x14e

@blackbeard0x14e Questions...while the Demo loads? https://github.com/blackbeard334/djoom3

Fallacies of Doom - RivieraDEV 19

Fallacies of Doom - RivieraDEV 19

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