Getting Mouse Coordinates in Gloss(Haskell) - haskell

I am trying to implement drag-and-drop functionality into a haskell gloss (scheduling) program of mine, but to do that I need to be able to read the coordinates of the mouse. I have been researching how to do this for multiple hours and am coming up empty, except for the fact that it is possible in GLUT, which gloss is based off of, but going that deep is over my head.
I was wondering if there is already some way to do this in gloss, and if not, what library should I switch to?
Thank you in advance!

For your serve function you'll want to handle an event such as:
serveWorld (EventKey (MouseButton LeftButton) Down xPos yPos) world = ...
Or perhaps you don't want to look for buttons but instead just motion? In that case serveWorld should handle EventMotion.
You might want to look at the gloss-draw example program, which is in the gloss-examples package.

Related

How did Epic Games achieve this 3D effect on their Fortnite site?

I have been looking at Epic Games' Fortnites Website and I am trying to figure out how they achieved the 3D effect on the page:
Epic Games' Fortnite website - scrolled down to 3rd slide
Does any one have any idea how to do it? I would really like something similar to a project I'm working on. I have found Three.js, but I am quite sure that is not the solution they went with.
For these types of questions, i can only recommend to install spector.js and have a look yourself. In short: everything you see is 100% faked.
I mean, that's always the case. In fact, if you want to build something like that, your first question should always be: how much of this can I fake and still get away with that?
In this example, it turns out: everything. Just open the devtools and click through all the assets in the network-tab. You will find these two textures:
looks familiar, right?
So what they appear to be doing is they are using three.js with some custom shaders to handle the translations, the flickering of the lights and the highlighting. These effects are computed using the normal-map and an additional mask-texture which I couldn't quite figure out what it does. But again, if you look at the scene in spector.js you can see the shaders used for every drawcall.
The only thing that is a bit more complex is the little robot-friend in the bottom left corner. But again, it's not 3d as in meshes and so on but rather a set of flat textured quads running a bones-animation thing.
I think that makes it a really great website after all.
Given that epic is building the unreal-engine I would suspect the original renders were done there. And I agree, the lighting looks really amazing :)
It is a simple parallax effect using animated sprite sheets.
Parallax effect is achieved by using several layers of images/video on top of one another in different Z-depth.
You can achieve the moving part by using the mousemove event to track the cursor.

Interactive geographic map in Phaser

I'm trying to create a interactive geographic map with Phaser framework that is similar to this http://preview.codecanyon.net/item/interactive-usa-map-html5/full_screen_preview/4527698 so what I was looking into is loading tile maps from JSON or CSV, but I'm not sure this is the right approach.
I know it's abstract question but I just wanted to be sure I'm moving into right direction and see if there are other ways to do this
I'm not sure a Tilemap is going to help you here. There's nothing 'tiled' or uniform about that map. While you could achieve it using Object placement in Tiled, I still think it's probably not the best route.
Personally I'd question the use of Phaser for something like this, and I wrote it! If I had to re-create the map you linked to, I would be looking at SVG and a library like paper.js instead, which just seems far more suited to this particular task.

OpenGL 3.2 Core Sprite Batch Example?

I have been tearing my hair out for a while over this. I need an OpenGL 3.2 Core (no deprecated stuff!) way to efficiently render many sprites, using batching (no instancing).
I've seen examples that do this with geometry alone, but mine also needs to send textures to it, I don't know how to do this.
I need a well done example of it working in action. And looking at how other libs like monogame and such do it isn't much help, because all I'm interested in is the GL code, and it has to have no deprecated stuff in it.
Basically I want to be able to efficiently render thousands+ of sprites, all having textures. The texture is just a spritesheet, so I just need to tell it to render a region of that spritesheet.
I'm disappointed in the amount of material available for programmable pipeline. To the point where it seems like it'd be so much easier to just say screw it and use fixed pipeline, even though I definitely don't want to do that.
So yeah, any full examples that do what I want? Or could somebody more knowledgable write one up? :)
A lot of the examples are "oh, here's how you render 1 triangle". Well that's great, except nobody needs to render only 1 triangle/quad. And they need to be textured in addition to that!
An example that uses VBOs/VAOs/EBOs
ALSO: this means the code can't use glTexPointer and that stuff, but just in raw VBOs/VAOs...
I saw this question and decided to write a little program that does some "sprite" rendering using points and gl_PointSize. I'm not quite sure what you mean by "batching" as opposed to "instancing," but my program uses the glDrawArraysInstanced() call so that I can render multiple points without needing my VBO to be variable sized. My code also doesn't texture the sprites, but that's easy enough to add in (upload the active texture index (the one that was active during your call to glTexSubImage), to a GLSL sampler2D using glUniform1i).
Anyway, here's the program I wrote: http://litherum.blogspot.com/2013/02/sprites-in-opengl-programmable-pipeline.html Hope you can learn from it!

How do I create a real-time rendering window from scratch?

I've been studying 3D graphics on my own for a while now and I want to get a greater understanding of just how everything works. What I would like to do is to create a simple game without using DirectX or OpenGL. I understand most of the math I believe, but the problem I am running up against is I do not know how to get control of the pixels being displayed in a window.
How do I specify what color I want each pixel in my window to be?
I understand I will probably run into issues with buffers and image shearing and probably terrible efficiency problems, but I want to create my own program so that I could see from the very lowest level, of the high level language, how the rendering process works. I really have no idea where to start though. I've figured out how to output BMPs, but I would like to have a running program spitting out 20+ frames per second. How do I accomplish this?
You could pick a environment that allows you to fill an array with values for pixels and display it as a bitmap. This way you come closest to poking RGB values in video memory. WPF, Silverlight, HTML5/Javascript can do this. If you do not make it full screen these technologies should suffice for now.
In WPF and Silverlight, use the WriteableBitmap.
In HTML5, use the canvas
Then it is up to you to implement the logic to draw lines, circles, bezier curves, 3D projections.
This is a lot of fun and you will learn a lot.
I'm reading between the lines that you're more interested in having full control over the rendering process from a low level, rather than having a specific interest in how to achieve that on one specific platform.
If that's the case then you will probably get a good bang for your buck looking at a library like SDL which provides you with a frame buffer that you can render to directly but abstracts away a lot of the platform specifics issues. It has been around for quite a while and there are some good tutorials to give you an idea of whether it's the kind of thing you're looking for - see this tutorial and the subsequent one in the same series, which should be enough to get you up and running.
You say you want to create some kind of a rendering engine, meaning desinging you own Pipeline and matrice classes. Which you are to use to transform 3D coordinates to 2D points.
When you have got the 2D points you've been looking for. You can use say for instance on windows, you can select a brush and draw you triangle values while coloring them at the same time.
I do not know why you would need Bitmaps, but if you want to practice say Texturing you can also do that yourself although off course on a weak computer this might take your frames per second significantly.
If you aim is to understand how rendering works on the lowest level. This is with no doubt a good practice.
Jt Schwinschwiga

Simple C/C++ library for triangle-intersection acceleration structure

I'm raytracing and would like to speed it up via some acceleration structure (kd-tree, BVH, whatever). I don't want to code it up myself. What I've tried so far:
Yanking the kd-tree out of pbrt. There are so many intra-dependencies that I couldn't succeed at this without pulling all of pbrt into my code.
CGAL's AABB tree. Frustratingly, this seems to return only the point of intersection. Without knowing which triangle the point came from, I can't efficiently interpolate color over the triangle. I'd love to just extend the notion of "Point" with color, but this doesn't seem possible without writing a lot of template code from scratch.
Writing my own. Okay so I wrote my own grid acceleration class, and it works, but it's nasty and inefficient.
So, if anyone can suggest a simple library that I can use for this purpose I'd really appreciate it! All I need is given a triangle soup and ray, find the closest intersection and return the index of that triangle.
Jaco Bikker wrote this series of tutorials: http://www.devmaster.net/articles/raytracing_series/part7.php
They're very helpful and he includes code at the end for a ray tracer using a kd-tree.
You might be able to use that.
The G3D engine has a ray tracing implementation. Not sure how efficient it is though. It shouldn't bee too much trouble to use the Tree implementation without the rest of the library.

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