VisualProspecting

Add jitpack to your repositories:

repositories {
    maven {
        url = "https://jitpack.io"
    }
}

Add Visual Prospecting in your dependencies:

dependencies {
    compile("com.github.GT-IMPACT:VisualProspecting:$lastVersion")
}

Usage as API

Please keep in mind that chunk coordinates are block coordinates divided by 16! When in doubt you may fall back on:

int chunkX = Utils.coordBlockToChunk(blockX);

// blockZ is the lowest block coordinate in a chunk. If you want 
// to iterate over all blocks in that particular chunk you need
// to add [0, ... 15] to it
int blockZ = Utils.coordChunkToBlock(chunkZ);

Whenever you detect a new ore vein you need to add custom network payloads and request the information from the logical server yourself. Please do your best to disallow a logical client from querying the complete server database as it would lead to potential abuse. So, please check if the player is allowed to prospect a dimension and location.

If you simply want to notify a logical client from the logical server you may send a ProspectingNotification to the logical client. It will be handled from the client. For example:

final World world;
final int blockX;
final int blockZ;
final int blockRadius;
final EntityPlayerMP entityPlayer;

if(world.isRemote == false) {
    final List<OreVeinPosition> foundOreVeins = VisualProspecting_API.LogicalServer.prospectOreVeinsWithinRadius(world.provider.dimensionId, blockX, blockZ, blockRadius);
    final List<UndergroundFluidPosition> foundUndergroundFluids = VisualProspecting_API.LogicalServer.prospectUndergroundFluidsWithingRadius(world, blockX, blockZ, VP.undergroundFluidChunkProspectingBlockRadius);

    VisualProspecting_API.LogicalServer.sendProspectionResultsToClient(entityPlayer, foundOreVeins, foundUndergroundFluids);
}

JourneyMap Custom Layer

VisualProspecting provides a light-weight API for custom and interactive layers. This API will keep all maps as optional mod at runtime and not crash you game if it is missing. You may instantiate ButtonManager to create your own logical button. Follow it up with an instance of LayerButton and register both in the VisualProspecting_API:

ButtonManager buttonManager = new ButtonManager("translation.key", "iconName");
LayerButton layerButton = new LayerButton(buttonManager);

VisualProspecting_API.LogicalClient.registerCustomButtonManager(buttonManager);
VisualProspecting_API.LogicalClient.registerJourneyMapButton(layerButton);

If you start the game now, you will see a new button in the menu!

First, you will implement ILocationProvider. This class is a container and will provide all information required to display your item on screen. It won't do any rendering.

class MyLocation implements ILocationProvider {

    public int getDimensionId() {
        return 0; // overworld
    }
    
    public int getBlockX() {
        return 0;
    }
    
    public int getBlockY() {
        return 65;
    }
    
    public int getBlockZ() {
        return 0;
    }
    
    public String getLabel() {
        return "Hello Minecraft";
    }
}

Next up, you'll extend LayerManager and implement the abstract function to generate cached List of your ILocationProvider implementation. You should only add whatever items are visible to this list. There are more methods to override, that will assist you with that. Take a look!

class MyLayerManager extends LayerManager {

    public static final MyLayerManager instance = new MyLayerManager();

    public MyLayerManager() {
        super(buttonManager);
    }
    
    protected List<? extends ILocationProvider> generateVisibleElements(int minBlockX, int minBlockZ, int maxBlockX, int maxBlockZ) {
        return Collections.singletonList(new MyLocation);
    }
}

You have finished the logical implementation of your custom map layer. Congratulations! Now it is time for the visual integration into the map. This example is provided for JourneyMap, but you might as well take a look at the other possibilities. Since you already implemented the button as a first step, you will need to follow it up with an implementation of DrawStep, an interface from JourneyMap. This class will receive an instance of MyLocation and perform the actual rendering.

class MyDrawStep implements DrawStep {

    private final MyLocation myLocation;
    
    public MyDrawStep(MyLocation myLocation) {
        this.myLocation = myLocation;
    }
    
    @Override
    public void draw(double draggedPixelX, double draggedPixelY, GridRenderer gridRenderer, float drawScale, double fontScale, double rotation) {
        final double blockSize = Math.pow(2, gridRenderer.getZoom());
        final Point2D.Double blockAsPixel = gridRenderer.getBlockPixelInGrid(myLocation.getBlockX(), myLocation.getBlockZ());
        final Point2D.Double pixel = new Point2D.Double(blockAsPixel.getX() + draggedPixelX, blockAsPixel.getY() + draggedPixelY);
        
        DrawUtil.drawLabel(myLocation.getText(), pixel.getX(), pixel.getY(), DrawUtil.HAlign.Center, DrawUtil.VAlign.Middle, 0, 180, 0x00FFFFFF, 255, fontScale, false, rotation);
    }
}

Continue with your own implementation of LayerRenderer. This class will cache all DrawSteps and provide it to JourneyMap whenever it is time to render.

class MyLayerRenderer extends LayerRenderer {

    public MyLayerRenderer() {
        // You may skip MyLayerManager and use an existing ButtonManager like "OreVeinLayerManager.instance"
        // Your custom layer will toggle with whatever button you specify here
        super(MyLayerManager.instance);
    }
    
    @Override
    public List<? extends ClickableDrawStep> mapLocationProviderToDrawStep(List<? extends ILocationProvider> visibleElements) {
        final List<MyDrawStep> drawSteps = new ArrayList<>();
        visibleElements.stream()
                .map(element -> (MyLocation) element)
                .forEach(location -> drawSteps.add(new MyDrawStep(location)));
        return drawSteps;
    }

}

That's already it! Now you need to register some of these classes. Forge's postInit is a good place for it:

VisualProspecting_API.LogicalClient.registerCustomLayer(MyLayerManager.instance);
VisualProspecting_API.LogicalClient.registerJourneyMapRenderer(new MyLayerRenderer());

Now you need to launch Minecraft, teleport to the right sport (/tp 0 80 0) and open JourneyMap.

If you want to extend support for your layer in other maps as well you already have half the work done. You just need to add implementations for the layer and element renderer.
For interactive layers you may take a look at extensions/implementations of WaypointProviderManager and ClickableDrawStep to get a head start.