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• I like to build my A - Team now.

I need loyal people who can trust and believe in a dream.

We cant pay now, you will recieve a lifetime percentage if the released game will give earnings.

What i need:
- Programmer c++
- Unity / Unreal - we must check whats possible, please share your experience with me.
- Sculpter, 3D Artist
- Animator
- Marketing / Promotion

What i do:
- Studio Owner
- Director
- Recruit exactly you
- Sounddesign
- Main theme composing
- Vocals
- Game design
- Gun, swords, shields and weapon design
- Character, plants and animal design

The game will be defintitly affected about our and your skills if you join the team.

Planned for the big Game:
- 1st person shooter
- online multiplayer
- character manipulation
- complete big open world with like lifetime actions and reactions
- gunstore with many items to buy
- specials like mini games

So if you are interested in joining a team with a nearly complete game idea, contact me now and tell me what you can do.

discord:
joerg federmann composing#2898

• I wasn't sure if this would be the right place for a topic like this so sorry if it isn't.
I'm currently working on a project for Uni using FreeGLUT to make a simple solar system simulation. I've got to the point where I've implemented all the planets and have used a Scene Graph to link them all together. The issue I'm having with now though is basically the planets and moons orbit correctly at their own orbit speeds.
I'm not really experienced with using matrices for stuff like this so It's likely why I can't figure out how exactly to get it working. This is where I'm applying the transformation matrices, as well as pushing and popping them. This is within the Render function that every planet including the sun and moons will have and run.
if (tag != "Sun") { glRotatef(orbitAngle, orbitRotation.X, orbitRotation.Y, orbitRotation.Z); } glPushMatrix(); glTranslatef(position.X, position.Y, position.Z); glRotatef(rotationAngle, rotation.X, rotation.Y, rotation.Z); glScalef(scale.X, scale.Y, scale.Z); glDrawElements(GL_TRIANGLES, mesh->indiceCount, GL_UNSIGNED_SHORT, mesh->indices); if (tag != "Sun") { glPopMatrix(); } The "If(tag != "Sun")" parts are my attempts are getting the planets to orbit correctly though it likely isn't the way I'm meant to be doing it. So I was wondering if someone would be able to help me? As I really don't have an idea on what I would do to get it working. Using the if statement is truthfully the closest I've got to it working but there are still weird effects like the planets orbiting faster then they should depending on the number of planets actually be updated/rendered.

• Learning game development in Unreal Engine could be a daunting task for someone who don’t know where to start, and a cumbersome process if you don’t organize your progression correctly. One thing commonly known by experienced developers and by people unfamiliar with coding: mastering a development language is a long and difficult task.
From blueprints to C++ in Unreal Engine
If you want to learn fast, you need a good learning strategy. Unreal Engine contains a very powerful tool which you can use to learn C++ faster: its blueprint system. Blueprints are extremely easy to learn (and you may already have a good knowledge of them). Thus you can conveniently use them as a guide for writing code in C++. This is the reason why I am writing a tutorial series on how to make the transition from Unreal Engine blueprints to C++.
Learn and practice C++
Following this tutorial, you’ll acquire new concepts of C++ programming in every chapter. Then following chapters will give you reasons to reuse and practice those same concepts. There’s no better way to wire you brain.
Link to the tutorial: [Tutorial] Learn C++ in Unreal Engine 4 by making a powerful camera
Please do send me as much feedback as you want. I’ll be considering every constructive remarks and taking them into consideration. Your feedback will help me to improve and update the existing chapters and to make the next one better.

View full story

• Learning game development in Unreal Engine could be a daunting task for someone who don’t know where to start, and a cumbersome process if you don’t organize your progression correctly. One thing commonly known by experienced developers and by people unfamiliar with coding: mastering a development language is a long and difficult task.
From blueprints to C++ in Unreal Engine
If you want to learn fast, you need a good learning strategy. Unreal Engine contains a very powerful tool which you can use to learn C++ faster: its blueprint system. Blueprints are extremely easy to learn (and you may already have a good knowledge of them). Thus you can conveniently use them as a guide for writing code in C++. This is the reason why I am writing a tutorial series on how to make the transition from Unreal Engine blueprints to C++.
Learn and practice C++
Following this tutorial, you’ll acquire new concepts of C++ programming in every chapter. Then following chapters will give you reasons to reuse and practice those same concepts. There’s no better way to wire you brain.
Link to the tutorial: [Tutorial] Learn C++ in Unreal Engine 4 by making a powerful camera
Please do send me as much feedback as you want. I’ll be considering every constructive remarks and taking them into consideration. Your feedback will help me to improve and update the existing chapters and to make the next one better.
• By mrDIMAS
Hello everyone! I need to fill lua table with functions from script file like this:
function init() end function update() end I need to create table on stack and fill it with this functions from specified file. How can I do this?

# C++ 2D Math Problem

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In the following code:

Point p = a[1];  center of rotation

for (int i = 0; I<4; i++)
{
int x = a.x - p.x;
int y = a.y - p.y;

a.x = y + p.x;
a.y = - x + p.y;
}

I am understanding that a 90 degree shift results in a change like:

xNew = -y

yNew = x

Could someone please explain how the two additions and subtractions of the p.x and p.y works?

Thank you,

Josheir

Edited by Josheir

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xNew = -y
yNew = x

This rotates a point/vector around the origin by 90 degrees

The original code snippet does the same (similar -- they're mirrored, so if using the same coordinate system it would be the reverse direction), except it rotates about a point other than the origin, which in this case is the center of the rectangle. It's effectively the same as rotating around the origin, except it offsets by the center point's position in order to treat the center point as the origin.

EDIT: for clarity, the two subtractions move the rectangle points to a position relative to the world origin that is the same as their position relative to their center point. Then they are rotated around the origin, then moved back (the two additions) to be relative to the center point instead of the world origin.

Edited by cmac

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So, is this correct:  The first two p's subtract the offset to regard the point not being the origin.  Than the computation is done again and p's are added to re translate it back to the origin.

The array is four integers held to be a shape of a grid of 8 cells (two columns,)  It's not really a rectangle.

I was playing around with the values (mirrored or not:)

xNew = -y

yNew = x

and got it working luckily.  I find it confusing that the second set of additions uses the first set that subtracts.  I think I've got it now but was hoping someone could do a simple explanation if there is anything else to explain!

The way that I got it working was I drew a circle with p.y in the center and a.y on the circumference with the difference being what I assumed to be  the y.  Likewise for the x values.

Thank you,

Josheir

Edited by Josheir

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Here's a badly drawn MSPaint depiction of what I described:

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If you know how to rotate around the origin, you can rotate around any point P like this:

• translate the whole picture so P becomes the origin,
• rotate around the origin,
• translate back so the origin becomes P

Does that help?

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Yes, all that helps; I'm pretty sure I understand it now.  I am a bit confused by the diagram though.  I'll go over my program again tomorrow but I do understand what you mean.  I need to translate this understandable concept into the understandability of the idea for a specific program.  Like I said, it's not really a rectangle, it's more complicated.

Thanks again,

Josheir

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Black dot = polygon center, red line = subtraction, green line = rotation, blue line = addition. As you can see, the point ends up at the desired point (90 degrees rotated around center).

Overall Alvaro's explanation was much more elegant and concise than mine, so just focus on that.

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hmm, cmc where did you translate the whole picture so P becomes the origin?

Appreciatively,

Josheir

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The subtraction (red line) translates the picture so that the polygon center has become (0,0).

Edited by cmac

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So in the image, there is P and center. P is a distance from center. The red line is P - C, this puts P a distance from origin. Green line is a rotation around origin = Pr. Blue line is Pr + C, moves the rotated point back out to be around center, and is the final rotated point.