svenstaro / derp

The derp game engine in D

Derp Project

Subprojects

• Derp is the library.
• Derper is the loader (runtime) for fully scripted applications.
• HerpDerp is the editor.

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# Derp - Engine

Derp is a very simple and yet to be powerful game engine for 2D and 3D games written in D. It is supposed to be a hybrid engine, providing both a D and a Lua interface. Thus it will be possible to write application code both in D (compiled) or Lua (scripted, dynamically loaded and executed with LuaD).

Goals

It is planned that derp features

• 2D and 3D Graphics via OpenGL
• audio via OpenAL
• simple, extensible resource loading, with many already supported types (ASSIMP)
• simple distribution (see also Derper)
• powerful scene graph with entity/component system
• full scene serialization (level files etc.)
• full access to engine API from LUA
• and probably more

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# Derper - Loader

Derper is a simple to use loader for fully scripted derp applications. Similar to the distribution method of Löve2D packages, derper will be able to open a package containing all application data. This should make it very easy to distribute (open-source) projects for all supported platforms.

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# HerpDerp - Editor

HerpDerp is a planned scene graph editor for the derp engine. This subproject has not yet been started.

derp's Issues

Advanced text rendering

Advanced features for text components:

• Rich text
• Word wrap

Code & Documentation Design

Decide on formatting rules for code and documentation.

Design lighting shader

Terrain Component

Depends on #12.

Network Api

hey, i started to write some network code. not stable yet.
https://github.com/Zoadian/D-Networking-API

what do you think? is it something we want in derp? or any suggestions how to improve it?

Compiling derp engine fails under dmd v2.060 linux

When I run make code compilation fails with this error message:

orange/util/Reflection.d(497): Error: function orange.util.Reflection.newInstance (TypeInfo_Class classInfo) is not
callable using argument types (const(TypeInfo_Class))
orange/util/Reflection.d(497): Error: cannot implicitly convert expression (classInfo) of type const(TypeInfo_Class) to string
make[1]: *** [lib/32/orange/util/Reflection.o] Error 1
make[1]: Leaving directory `/home/erdem/Çalışmalar/derp/externals/orange'
make: *** [dep] Error 2

I tried to delete orange directory. Reclone orange library and it compiles fine.

Timing properties in window

• last frame time
• last FPS
• age
• average FPS

Light Component

Depends on #13

Input management

InputManager and an abstract InputListener... the usual ;)

Fix compilation on all platforms

Manage Resource Releasing

Scene resources for example need to free the assimp data when not required anymore.

didn't you fix that? :D if not we should fix it upstream

orange/xml/PhobosXml.d(2935): Error: & _D12TypeInfo_Aya6__initZ.getHash is not nothrow
orange/xml/PhobosXml.d(2933): Error: function orange.xml.PhobosXml.hash 'hash' is nothrow yet may throw

Child node scale affects offset by parent position

This should not be the case, obviously. The child scale should only affect the offset of all child-child nodes, not the offset of the child-node itself.

Implement Vector/Matrix/Quaternion with SIMD support

Implement a replacement for gl3n, with added support for simd instuctions.

I'm Currently benchmarking different ways to use simd.

any features you want them to have?

Basic Dependency Selection

Things we need and have to find / decide on:

• Linear Algebra
• Graphics Engine

KissDiscuss now!

Fix shader on Catalyst Drivers

Currently herpderp will not run on my system with Catalyst for driver, Catalyst returns the message "Failed to compile shader" when I try to run herpderp while trying to use the fragment shader.

Plan GameState structure

There have to be gamestates... what do we need, how can they be implemented?

• intelligent resource loading/unloading
• transitions
• stacking / peeking

Implement render system

Proposed call stack

• `Window.render()?
• each viewport in the window: viewport.render()
• viewport.camera.render()
• camera.node.rootNode.render()
• recursively, each child node node.render()
• each component: component.render()

MeshComponent and SpriteComponent override the render() method to do their stuff.

Suggestions?

Windows Support

do we support windows yet?
i know 3 people who want to test derp, but don't want to install linux.

(i'm stll on the project btw, just no spare time atm)

Node.position should be relative to parent, not world

Fix the matrices, guys!

More Sprite Properties

• Origin
• Sub-Rect
• Blending Mode (use some kind of materials!?)

Implement 9-Patch Sprite for GUI

Read the android developer guide about how 9-patches work.

Text rendering

Low-level text rendering

• Font loading
• Render text to a texture
• Calculate text width
• Colours (should be fairly easy with the vertex color attribute - would even support gradients)
• Maybe the TextComponent should be/have a sprite internally?

Implement basic mesh component

Plan Scene Graph

How will the entity/component system look like?

Keep in mind

• extensibility
• performance
• initialization/deinitialization order
• deep serialization (orange)