• Announcements

    • khawk

      Download the Game Design and Indie Game Marketing Freebook   07/19/17

      GameDev.net and CRC Press have teamed up to bring a free ebook of content curated from top titles published by CRC Press. The freebook, Practices of Game Design & Indie Game Marketing, includes chapters from The Art of Game Design: A Book of Lenses, A Practical Guide to Indie Game Marketing, and An Architectural Approach to Level Design. The GameDev.net FreeBook is relevant to game designers, developers, and those interested in learning more about the challenges in game development. We know game development can be a tough discipline and business, so we picked several chapters from CRC Press titles that we thought would be of interest to you, the GameDev.net audience, in your journey to design, develop, and market your next game. The free ebook is available through CRC Press by clicking here. The Curated Books The Art of Game Design: A Book of Lenses, Second Edition, by Jesse Schell Presents 100+ sets of questions, or different lenses, for viewing a game’s design, encompassing diverse fields such as psychology, architecture, music, film, software engineering, theme park design, mathematics, anthropology, and more. Written by one of the world's top game designers, this book describes the deepest and most fundamental principles of game design, demonstrating how tactics used in board, card, and athletic games also work in video games. It provides practical instruction on creating world-class games that will be played again and again. View it here. A Practical Guide to Indie Game Marketing, by Joel Dreskin Marketing is an essential but too frequently overlooked or minimized component of the release plan for indie games. A Practical Guide to Indie Game Marketing provides you with the tools needed to build visibility and sell your indie games. With special focus on those developers with small budgets and limited staff and resources, this book is packed with tangible recommendations and techniques that you can put to use immediately. As a seasoned professional of the indie game arena, author Joel Dreskin gives you insight into practical, real-world experiences of marketing numerous successful games and also provides stories of the failures. View it here. An Architectural Approach to Level Design This is one of the first books to integrate architectural and spatial design theory with the field of level design. The book presents architectural techniques and theories for level designers to use in their own work. It connects architecture and level design in different ways that address the practical elements of how designers construct space and the experiential elements of how and why humans interact with this space. Throughout the text, readers learn skills for spatial layout, evoking emotion through gamespaces, and creating better levels through architectural theory. View it here. Learn more and download the ebook by clicking here. Did you know? GameDev.net and CRC Press also recently teamed up to bring GDNet+ Members up to a 20% discount on all CRC Press books. Learn more about this and other benefits here.
Sign in to follow this  
Followers 0
gchewood

Problem drawing model with multiple textures in XNA

4 posts in this topic

I have a model with multiple materials/textures in .X format. If I load it and draw with BasicEffect, it renders just fine.

However, I need do it with a custom effect and so far my efforts are in vain. The model is being rendered with just one of the textures being used for all parts (where it shouldn't be).

So here's my loading of the model:

 

private void LoadModel(string assetName, out Model model)
        {
            model = content.Load<Model>(assetName);
            foreach (ModelMesh mesh in model.Meshes)
            {
                foreach (ModelMeshPart part in mesh.MeshParts)
                {
                    BasicEffect basicEffect = part.Effect as BasicEffect;
                    if (basicEffect != null)
                        modelTextures[mesh.GetHashCode()] = basicEffect.Texture;
                    
                    part.Effect = myEffect;
                }
            }
        }

modelTextures being an array of Texture2Ds.

 

And then here's my drawing the model:

 

public void DrawModel()
        {
            foreach (ModelMesh m in model.Meshes)
            {
                foreach (Effect e in m.Effects)
                {
                        e.CurrentTechnique = e.Techniques["Shadow"];
                        e.Parameters["world"].SetValue(Matrix.CreateTranslation(0, 100, 0));
                        e.Parameters["view"].SetValue(view);
                        e.Parameters["projection"].SetValue(projection);
                        e.Parameters["colorMap"].SetValue(modelTextures[m.GetHashCode()]);
                }
                m.Draw();
            }
        }

This actually works fine for a different model I've got (that someone else made). But not my model!

But since my model renders just fine with the basiceffect, I don't know where the problem is I should be trying to fix?

Worst case scenario, I can break my model up into separate models, each with a single texture. But I prefer a real solution,

any help would be very much appreciated!

 

Thanks

Edited by gchewood
0

Share this post


Link to post
Share on other sites
Look how you're storing your textures... indexed by ModelMesh's hash instead of ModelMeshPart's. So if you have a model that has two ModelMeshParts with different textures, that would explain the bug you're seeing.
0

Share this post


Link to post
Share on other sites

Aha. How would I adjust it to fix that then? Cos you draw a model by looping through the ModelMeshes don't you. So how can the shader set different values

for 2 different ModelMeshParts?

Edited by gchewood
0

Share this post


Link to post
Share on other sites
Yeah, I see what you mean. Of course, ModelMesh handles this ok with the default BasicEffect, so it can be done.

You have three options:

1) Clone your effect before assigning it to ModelMeshPart.Effect. That creates a unique instance of your effect (which is what I expect each ModelMeshPart has by default... a unique instance of BasicEffect). Assign each effect its appropriate texture. And then you only need to update the parameters that change each frame in your DrawModel method (e.g. view, world, etc...). This is probably the easiest solution; but Clone'ing an effect creates a new GPU resource, so you should remember to call Dispose() on it when you're completely finished with it - you have to manage its lifetime manually since it wasn't loaded through the ContentManager.

2) Avoid using ModelMesh.Draw (which submits a draw call for each ModelMeshPart). Instead loop through all the ModelMeshParts and use DrawIndexedPrimitives after setting the corresponding Effect parameters and Apply()'ing the changes. This way you can still keep a single Effect instance. ModelMeshPart and its ModelMesh parent should have all the necessary information needed for the parameters to DrawIndexedPrimitives, but if you're not familiar with DrawIndexedPrimitives it might take a while to figure it all out. (DrawIndexedPrimitives is essentially what ModelMesh.Draw uses internally).

3) Change your model so it has two ModelMeshes instead of one ModelMesh and two ModelMeshParts :-). Edited by phil_t
0

Share this post


Link to post
Share on other sites

Thanks phil_t,  a nice encyclopedic answer!

 

I'll probably just go with #3 cos it's the only one I know how to do without further effort!

0

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0