LWJGL - Voxel Engine

[Pauler]

Are you talking about a 3D triangle or a 2D triangle?

I want to draw my cubes using 12 tringles instead of 6 quads.

[TH3Fatal]

Are you talking about a 3D triangle or a 2D triangle?

I want to draw my cubes using 12 tringles instead of 6 quads.

Would u not render the points this way giving u 2 triangles per face
1   /3
|  / |
2/   4

0,1
0,0
1,1
1,0

This is just the x and y but you can just adapt it for each of the other faces.

[Longor1996]

Hello there.

It's very easy to split a Quad into two triangles.

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// Label your 4 Vertices from A-D A GL11.glTexCoord2f(spriteX, spriteY + small);           GL11.glVertex3f(x1, y1 + height, z1); B GL11.glTexCoord2f(spriteX, spriteY);                     GL11.glVertex3f(x1, y1 + height, z1 + length); C GL11.glTexCoord2f(spriteX + small, spriteY);           GL11.glVertex3f(x1 + width, y1 + height, z1 + length); D GL11.glTexCoord2f(spriteX + small, spriteY + small); GL11.glVertex3f(x1 + width, y1 + height, z1);

Clockwise:
Triangle A is: A B C
Triangle B is: A C D

Result:

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// Triangle A A GL11.glTexCoord2f(spriteX, spriteY + small);           GL11.glVertex3f(x1, y1 + height, z1); B GL11.glTexCoord2f(spriteX, spriteY);                     GL11.glVertex3f(x1, y1 + height, z1 + length); C GL11.glTexCoord2f(spriteX + small, spriteY);           GL11.glVertex3f(x1 + width, y1 + height, z1 + length); // Triangle B A GL11.glTexCoord2f(spriteX, spriteY + small);           GL11.glVertex3f(x1, y1 + height, z1); C GL11.glTexCoord2f(spriteX + small, spriteY);           GL11.glVertex3f(x1 + width, y1 + height, z1 + length); D GL11.glTexCoord2f(spriteX + small, spriteY + small); GL11.glVertex3f(x1 + width, y1 + height, z1);

I hope this helps.

- Longor1996

Games published by our own members! Check 'em out!

[Pauler]

Thank you. It work but the problem is that the face culling doesn't draw the bot face anymore. It has something to do if it is clockwise or not.

[Longor1996]

Hi Pauler.

Thank you. It work but the problem is that the face culling doesn't draw the bot face anymore. It has something to do if it is clockwise or not.

It's incredible easy! Just flip the edge vertices.

Clockwise:
Triangle A is: A B C
Triangle B is: A C D

Counter-Clockwise:
Triangle A is: C B A
Triangle B is: D C A

- Longor1996

[Pauler]

<a href="http://www.youtube.com/v/7sfS5fmzDjk?version=3&amp;hl=en_US&amp;start=" target="_blank">http://www.youtube.com/v/7sfS5fmzDjk?version=3&amp;hl=en_US&amp;start=</a>

Sadly, water can't expand to another chunk.

[steg90]

Looking cool, keep up the good work!

[Vermeer]

Wow that's fantastic! I love how that's all working.

Sadly, water can't expand to another chunk.

I'm sure you will find a way to solve that. When I did the water on my map I stored the water In another array, this was partly because I used a second render pass to draw it semi -transparent. But it also solved the problem of it not being bound to chunks.

I'm not suggesting you do that, but a temporary list of moving water may help get around that. Or some good methods that deal with chunk boundaries.  Looks great!

[Pauler]

I found some time and started working on the engine again, but I still cannot get the holding cube right. Can someone send me a working piece of code about the holding cube?

Some of the strangle results:

<a href="http://www.youtube.com/v/VFrsQmG3zQw?version=3&amp;hl=en_US&amp;start=" target="_blank">http://www.youtube.com/v/VFrsQmG3zQw?version=3&amp;hl=en_US&amp;start=</a>

Paul.

[Mike]

Draw it last and don't do any depth testing.

Mike

Games published by our own members! Check 'em out!

[Vermeer]

I looks like you are not translating and rotating it properly.

this is from a page on my blockworld page

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// draw the block the player is holding      GL11.glLoadIdentity();       //move the camera      GL11.glRotatef(20, 1.0f, 0, 0);  //lookupdown      GL11.glRotatef(360.0f - yrot, 0, 1.0f, 0); //360.0f - yrot      GL11.glTranslatef(-xpos, (-walkbias/3) - 0.25f - (float)playerheight - hedHeight, -zpos);             //move the block infront of the player      float xblokpos = xpos - (float) Math.sin((yrot-18) * piover180) * 0.24f;       float zblokpos = zpos - (float) Math.cos((yrot-18) * piover180) * 0.24f;                   GL11.glTranslatef(xblokpos, playerheight+1.83f, zblokpos);       GL11.glRotatef(340.0f + yrot, 0,1f, 0f);

its rotated to the side of the player by 18, and tilted down by 20 (GL11.glRotatef(20, 1.0f, 0, 0); )
Once the camera is rotated, I place the block infront of the player with xblokpos zblockpos (the block is 0.24 units from the player camera)
The block is then rotated to maintain its relative rotation to the player
I have also reduced the effect of the walkbias by /3 to minimise, but not remove the bobbing effect on the block, as its close to the camera.

Hope this is of some help. The values you want to use may be trial and error! To get the look you want to have.

you can also download my code, its on there somewhere. This part is halfway down the render method

[steg90]

I don't translate the position - just set identity and position the cube after.

I just do:

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glLoadIdentity();      GL11.glRotatef(10, 0, 0, 1);    GL11.glTranslatef(-0.05f, (walkbias / 2.3f) + 0.9f, 0.4f);        // draw cube

The above is called after my camera has been translated.

[Pauler]

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glLoadIdentity();      GL11.glRotatef(10, 0, 0, 1);    GL11.glTranslatef(-0.05f, (walkbias / 2.3f) + 0.9f, 0.4f);        // draw cube

What walkbias is?

[steg90]

It's just a value that is calculated to get a bobbing effect - I got the idea from Vermeer who I believe got it from one of nehe's tuts.

You can just do:

GL11.glTranslatef(-0.05f, 0.9f, 0.4f);

You may have to play around with the values dependant on your camera position.

[Vermeer]

Yes walkbias is from NEHE's tutorial.  I have scaled it down by 2.3 as the motion does not need to be as pronounced as the full bias of the character.

[Pauler]

Thank you all for your help. I used steg90's method, and it worked. I was expecting something more compilicated with usage of trigonometry to tell you the truth.

-

My current problem is that from some angles, players cannot see the rest of the blocks through a transparent block. At some points it seems like there are no other blocks behind the transparent ones like water. I don't know if my explanation is good enough to understand. I am not sure what causes that.

Paul.

[Longor1996]

Thank you all for your help. I used steg90's method, and it worked. I was expecting something more compilicated with usage of trigonometry to tell you the truth.

-

My current problem is that from some angles, players cannot see the rest of the blocks through a transparent block. At some points it seems like there are no other blocks behind the transparent ones like water. I don't know if my explanation is good enough to understand. I am not sure what causes that.

Paul.

To fix this problem (almost):

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GL11.glEnable(GL11.GL_BLEND);          GL11.glBlendFunc(GL11.GL_SRC_ALPHA,GL11.GL_ONE_MINUS_SRC_ALPHA);          GL11.glAlphaFunc(GL11.GL_GREATER, (float) 0.1);

And then you will also have to do depth-sort your chunks.
Then render opaque things front-to-back, and then render back-to-front transparent things.

Example:

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List<?> visibleChunks = ???; Collections.sort(visibleChunks,frontBackDistanceSort); for(int n = 0; n < visibleChunks.size(); n++)     visibleChunks.get(n).renderCall(OPAQUE); for(int n = visibleChunks.size()-1; n >= 0; n--)     visibleChunks.get(n).renderCall(TRANSPARENT);

- Longor1996

[HeroesGraveDev]

The creator of Dysis (Arktos) got around that problem by rendering chunks in 2 passes.

The first pass is all the normal blocks.
The second is water and all the other semi-transparent blocks

(Make sure all chunks are rendered by the first pass before going onto the second pass.)

[Pauler]

Wow, after adding some simple checks to try your solution the game crashes everytime I try to spawn water and this is the error log.

I googled it and some people had this error at minecraft. The possible reason was the graphics card driver, but it is the first time I get this. (Also, first time I use transparency.)

http://pastebin.java-gaming.org/d6d37427e58

Paul.

[Vermeer]

I used 2 render passes for transparent water etc...

[Pauler]

I used 2 render passes for transparent water etc...

Just tried that and it worked.

Thank you, HeroesGraveDev.

[Pauler]

This is the current state of the voxel engine. I am not sure if I will continue working on it.

<a href="http://www.youtube.com/v/SIGCNIGiL4M?version=3&amp;hl=en_US&amp;start=" target="_blank">http://www.youtube.com/v/SIGCNIGiL4M?version=3&amp;hl=en_US&amp;start=</a>

[HeroesGraveDev]

You going to rename the title sometime soon?

[Vermeer]

That is looking and working very well. It seems a shame to stop progress on it, but I guess you have an idea for another game now you have developed all the skills with this.

Or maybe you could do a UI and crafting?

I like your water, looks cool, your project has really developed so far!

[Pauler]

Or maybe you could do a UI and crafting?

I may give it a shot.

You going to rename the title sometime soon?

Better? Or you have anything else in mind?

[Pauler]

<a href="http://www.youtube.com/v/89c9Bq1SbWY?version=3&amp;hl=en_US&amp;start=" target="_blank">http://www.youtube.com/v/89c9Bq1SbWY?version=3&amp;hl=en_US&amp;start=</a>

*Added a simple sky.


I still have the problem I mentioned some posts before.

My current problem is that from some angles, players cannot see the rest of the blocks through a transparent block. At some points it seems like there are no other blocks behind the transparent ones like water. I don't know if my explanation is good enough to understand. I am not sure what causes that.

Paul.

[Vermeer]

If you render the water first at any point, the depth test will prevent terrain being drawn behind it.  Draw all solid terrain first. Then transparent things in s second pass. That may solve it

[Pauler]

If you render the water first at any point, the depth test will prevent terrain being drawn behind it.  Draw all solid terrain first. Then transparent things in s second pass. That may solve it

I already draw the blocks at 2 passes. But it seems that each kind of transparent block need to be renders are different pass. And the problem is that I cant really find a way to do that automatically, yet

[RobinB]

Not each kind, you need to render the transparent blocks from back to front.
So you always need to render towards the player.

[pitbuller]

Not each kind, you need to render the transparent blocks from back to front.
So you always need to render towards the player.

You only want to render transparent objects back to front but all else from front to back.

Simple rendering order is like this.

1. Render all opaque. Depth test on. Depth writes On. Front to back.
2. Render all alpha tested. Depth test on. Depth writes On. Front to back.
3. Render all transparent. Depth Test on. Depth writes Off. Back to front. Enable blending.(use premultiplied alpha)
4. Render ui. Depth test off. Depth writes off. Back to front. Enable blending.

These simple rules work 90% of cases.