Update Grid Rendering Pipeline
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# Grid Rendering Pipeline
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## Overview
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The Grid rendering pipeline handles multi-layer tilemap rendering with chunk-based caching for optimal performance. It supports arbitrary numbers of rendering layers, viewport culling, zoom, and entity rendering.
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**Parent Page:** [[Grid-System]]
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**Related Pages:**
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- [[Performance-and-Profiling]] - Metrics and profiling tools
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- [[Entity-Management]] - Entity rendering within grids
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- [[Grid-TCOD-Integration]] - FOV and pathfinding (partially in transition)
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**Key Files:**
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- `src/UIGrid.cpp::render()` - Main rendering orchestration
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- `src/GridLayers.cpp` - ColorLayer and TileLayer rendering
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- `src/UIGrid.cpp::renderChunk()` - Per-chunk RenderTexture management
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**Related Issues:**
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- [#123](../../issues/123) - Chunk-based Grid Rendering (Closed - Implemented)
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- [#148](../../issues/148) - Dirty Flag RenderTexture Caching (Closed - Implemented)
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- [#147](../../issues/147) - Dynamic Layer System (Closed - Implemented)
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- [#113](../../issues/113) - Batch Operations API (Open - includes FOV access discussion)
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- [#115](../../issues/115) - SpatialHash for entity culling (Open)
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---
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## Architecture Overview
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### Layer-Based Rendering
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Grids render content through **layers** rather than per-cell properties. Each layer is either a `ColorLayer` (solid colors) or `TileLayer` (texture sprites).
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**Render order is determined by z_index:**
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- Layers with `z_index < 0` render **below** entities
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- Entities render at the z=0 boundary
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- Layers with `z_index >= 0` render **above** entities (overlays)
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Within each group, lower z_index values render first (behind higher values).
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```
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z_index: -3 -2 -1 0 +1 +2
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↓ ↓ ↓ ↓ ↓ ↓
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[background] [tiles] [ENTITIES] [fog] [UI overlay]
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```
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**Implementation:** See `UIGrid::render()` which iterates layers in z_index order, inserting entity rendering at the 0 boundary.
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### Chunk-Based Caching
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Large grids are divided into **chunks** (regions of cells). Each chunk maintains its own `sf::RenderTexture` that caches the rendered result.
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**Key concepts:**
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- Chunk size is implementation-defined (currently ~256 cells per dimension)
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- Only chunks intersecting the viewport are considered for rendering
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- Each chunk tracks whether its content is "dirty" (needs redraw)
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- Static content renders once, then the cached texture is reused
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**Implementation:** See `UIGrid::renderChunk()` for chunk texture management.
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### Dirty Flag Propagation
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When layer content changes, only affected chunks are marked dirty:
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1. `layer.set(x, y, value)` marks the containing chunk as dirty
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2. On next render, dirty chunks redraw to their RenderTexture
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3. Clean chunks simply blit their cached texture
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This means a 1000x1000 grid with one changing cell redraws only ~1 chunk, not 1,000,000 cells.
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**Implementation:** Dirty flags propagate through `UIGrid::markDirty()` and are checked in `UIGrid::render()`.
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---
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## Render Pipeline Stages
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### Stage 1: Viewport Calculation
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Calculate which chunks and cells are visible based on camera position, zoom, and grid dimensions.
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**Key properties:**
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- `center` / `center_x`, `center_y` - Camera position in pixel coordinates (within grid space)
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- `zoom` - Scale factor (1.0 = normal, 2.0 = 2x magnification)
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- `size` - Viewport dimensions in screen pixels
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**Implementation:** Viewport bounds calculated at start of `UIGrid::render()`.
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### Stage 2: Below-Entity Layers
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For each layer with `z_index < 0`, sorted by z_index:
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1. Determine which chunks intersect viewport
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2. For each visible chunk:
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- If dirty: redraw layer content to chunk's RenderTexture
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- Draw chunk's cached texture to output
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### Stage 3: Entity Rendering
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Entities render at the z=0 boundary:
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1. Iterate entity collection
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2. Cull entities outside viewport bounds
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3. Draw visible entity sprites at interpolated positions
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**Note:** Entity culling is currently O(n). SpatialHash optimization planned in [#115](../../issues/115).
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### Stage 4: Above-Entity Layers
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For each layer with `z_index >= 0`, sorted by z_index:
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- Same chunk-based rendering as Stage 2
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- These layers appear as overlays (fog, highlights, UI elements)
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### Stage 5: Final Compositing
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All rendered content exists in the grid's output RenderTexture, which is drawn to the window in a single operation.
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---
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## Performance Characteristics
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**Static Grids:**
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- Near-zero CPU cost after initial render
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- Cached chunk textures reused frame-to-frame
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- Only viewport calculation and texture blitting
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**Dynamic Grids:**
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- Cost proportional to number of dirty chunks
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- Single-cell changes affect only one chunk
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- Bulk operations should batch changes before render
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**Large Grids:**
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- 1000x1000+ grids render efficiently
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- Only visible chunks processed
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- Memory scales with grid size (chunk textures)
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**Profiling:** Use `mcrfpy.getMetrics()` or the F3 overlay to see render times. See [[Performance-and-Profiling]].
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---
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## FOV and Perspective System (In Transition)
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**Current Status:** The FOV computation (`compute_fov()`, `is_in_fov()`) works correctly for pathfinding and visibility queries. However, the automatic fog-of-war overlay system is **not currently connected** to the new layer architecture.
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**What works:**
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- `grid.compute_fov(x, y, radius)` - Computes which cells are visible
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- `grid.is_in_fov(x, y)` - Queries visibility of a specific cell
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- Pathfinding uses walkable/transparent properties correctly
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**What's in transition:**
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- Per-entity perspective (`UIGridPointState`) not yet exposed to Python
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- Automatic fog overlay rendering disconnected from layer system
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- Batch FOV data access being designed ([#113 discussion](../../issues/113))
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**Current workaround - Manual fog layer:**
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```python
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# Create a fog overlay layer (positive z_index = above entities)
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fog_layer = grid.add_layer("color", z_index=1)
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# After computing FOV, update fog colors
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grid.compute_fov(player.grid_x, player.grid_y, radius=10)
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for x in range(grid.grid_x):
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for y in range(grid.grid_y):
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if not grid.is_in_fov(x, y):
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# Dim color for non-visible cells
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fog_layer.set(x, y, mcrfpy.Color(0, 0, 0, 192))
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else:
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# Transparent for visible cells
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fog_layer.set(x, y, mcrfpy.Color(0, 0, 0, 0))
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```
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**Limitation:** This O(n²) iteration is inefficient for large grids. Batch operations ([#113](../../issues/113)) will address this with patterns like `cells_in_radius()` iterators.
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---
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## Layer Techniques
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### Multiple Overlay Layers
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You can pre-create multiple overlay layers and toggle between them:
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```python
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# Create several overlay options
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highlight_layer = grid.add_layer("color", z_index=1)
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danger_layer = grid.add_layer("color", z_index=2)
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fog_layer = grid.add_layer("color", z_index=3)
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# Populate each with different data...
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# highlight_layer shows selected cells
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# danger_layer shows enemy threat zones
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# fog_layer shows visibility
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# Toggle visibility to switch which overlay shows
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def show_danger_zones():
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highlight_layer.visible = False
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danger_layer.visible = True
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fog_layer.visible = False
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def show_fog_of_war():
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highlight_layer.visible = False
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danger_layer.visible = False
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fog_layer.visible = True
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```
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### Z-Index Reordering
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Change layer order at runtime by modifying z_index:
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```python
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# Bring a layer to front
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important_layer.z_index = 100
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# Send a layer behind entities
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background_layer.z_index = -10
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```
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**Note:** Changing z_index marks the layer dirty, triggering re-render of affected chunks.
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### Constructor `layers={}` Limitations
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The `layers={}` constructor argument is convenient but limited:
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```python
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# This creates layers, but ALL get negative z_index (below entities)
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grid = mcrfpy.Grid(
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grid_size=(50, 50),
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layers={"ground": "color", "terrain": "tile", "overlay": "color"}
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)
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# Result: ground=-3, terrain=-2, overlay=-1 (all below entities!)
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```
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**For overlays above entities, use `add_layer()` explicitly:**
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```python
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grid = mcrfpy.Grid(grid_size=(50, 50), layers={})
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ground = grid.add_layer("color", z_index=-2)
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terrain = grid.add_layer("tile", z_index=-1)
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overlay = grid.add_layer("color", z_index=1) # Above entities!
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```
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---
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## Migration from Legacy API
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Prior to the layer system, grids had built-in per-cell rendering via `UIGridPoint` properties. Here's how to recreate that behavior:
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### Legacy Pattern (Pre-November 2025)
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```python
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# OLD API (no longer works):
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grid = mcrfpy.Grid(50, 50, 16, 16)
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cell = grid.at(x, y)
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cell.tilesprite = 42 # Sprite index
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cell.color = (255, 0, 0) # Background color
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```
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### Equivalent Modern Pattern
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```python
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# NEW API - explicit layers:
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grid = mcrfpy.Grid(grid_size=(50, 50), pos=(0, 0), size=(400, 400))
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# Grid creates a default TileLayer; access it:
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tile_layer = grid.layers[0]
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tile_layer.set(x, y, 42) # Sprite index
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# For background colors, add a ColorLayer behind tiles:
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color_layer = grid.add_layer("color", z_index=-2) # Behind default tile layer
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color_layer.set(x, y, mcrfpy.Color(255, 0, 0))
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```
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### Recreating Old Three-Layer Rendering
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The legacy system rendered: background color → tile sprite → FOV overlay.
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```python
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# Create grid with no default layers
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grid = mcrfpy.Grid(
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grid_size=(50, 50),
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pos=(100, 100),
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size=(400, 400),
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texture=tileset,
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layers={}
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)
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# Layer 1: Background colors (z=-2, behind everything)
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background = grid.add_layer("color", z_index=-2)
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# Layer 2: Tile sprites (z=-1, above background, below entities)
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tiles = grid.add_layer("tile", z_index=-1, texture=tileset)
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# Layer 3: FOV overlay (z=+1, above entities)
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fog = grid.add_layer("color", z_index=1)
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# Now populate layers as needed
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background.fill(mcrfpy.Color(20, 20, 30)) # Dark blue background
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for x in range(50):
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for y in range(50):
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tiles.set(x, y, calculate_tile_index(x, y))
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# FOV overlay updated after compute_fov() calls
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```
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---
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## Common Issues
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### Issue: Layer Changes Don't Appear
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**Cause:** Layer content changed but chunk not marked dirty.
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**Fix:** Use layer methods (`set()`, `fill()`) which automatically mark dirty. Direct property manipulation may bypass dirty flagging.
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### Issue: Overlay Appears Behind Entities
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**Cause:** Layer z_index is negative.
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**Fix:** Use `z_index >= 0` for overlays:
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```python
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overlay = grid.add_layer("color", z_index=1) # Not z_index=-1
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```
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### Issue: Performance Degrades with Many Changes
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**Cause:** Each `set()` call can mark a chunk dirty; many scattered changes = many chunk redraws.
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**Fix:** Batch logically-related changes. For bulk updates, consider:
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```python
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# Less efficient: 10,000 individual calls
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for x in range(100):
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for y in range(100):
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layer.set(x, y, value)
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# More efficient when available: bulk fill
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layer.fill(mcrfpy.Color(0, 0, 0)) # Single operation
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```
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Batch operations API ([#113](../../issues/113)) will provide more patterns.
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---
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## API Quick Reference
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**Grid Properties:**
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- `center`, `center_x`, `center_y` - Camera position (pixels in grid space)
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- `zoom` - Scale factor
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- `layers` - List of layer objects, sorted by z_index
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- `fill_color` - Grid background (behind all layers)
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**Grid Methods:**
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- `add_layer(type, z_index, texture)` - Create new layer
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- `remove_layer(layer)` - Remove a layer
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**Layer Properties:**
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- `z_index` - Render order
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- `visible` - Show/hide layer
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- `grid_size` - Dimensions (read-only)
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**Layer Methods:**
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- `set(x, y, value)` - Set cell (color or sprite index)
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- `at(x, y)` - Get cell value
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- `fill(value)` - Fill all cells
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---
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**Navigation:**
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- [[Grid-System]] - Parent page, layer concepts
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- [[Grid-TCOD-Integration]] - FOV computation details
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- [[Performance-and-Profiling]] - Metrics and optimization
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- [[Entity-Management]] - Entity rendering
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---
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# Grid Rendering Pipeline
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## Overview
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The Grid rendering pipeline handles multi-layer tilemap rendering with chunk-based caching for optimal performance. It supports arbitrary numbers of rendering layers, viewport culling, zoom, and entity rendering.
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**Parent Page:** [[Grid-System]]
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**Related Pages:**
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- [[Performance-and-Profiling]] - Metrics and profiling tools
|
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- [[Entity-Management]] - Entity rendering within grids
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- [[Grid-TCOD-Integration]] - FOV and pathfinding (partially in transition)
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**Key Files:**
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- `src/UIGrid.cpp::render()` - Main rendering orchestration
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- `src/GridLayers.cpp` - ColorLayer and TileLayer rendering
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- `src/UIGrid.cpp::renderChunk()` - Per-chunk RenderTexture management
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**Related Issues:**
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- [#123](../../issues/123) - Chunk-based Grid Rendering (Closed - Implemented)
|
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- [#148](../../issues/148) - Dirty Flag RenderTexture Caching (Closed - Implemented)
|
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- [#147](../../issues/147) - Dynamic Layer System (Closed - Implemented)
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- [#113](../../issues/113) - Batch Operations API (Open - includes FOV access discussion)
|
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- [#115](../../issues/115) - SpatialHash for entity culling (Open)
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---
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## Architecture Overview
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### Layer-Based Rendering
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Grids render content through **layers** rather than per-cell properties. Each layer is either a `ColorLayer` (solid colors) or `TileLayer` (texture sprites).
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|
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**Render order is determined by z_index:**
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- Layers with `z_index < 0` render **below** entities
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- Entities render at the z=0 boundary
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- Layers with `z_index >= 0` render **above** entities (overlays)
|
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Within each group, lower z_index values render first (behind higher values).
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|
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```
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z_index: -3 -2 -1 0 +1 +2
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↓ ↓ ↓ ↓ ↓ ↓
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[background] [tiles] [ENTITIES] [fog] [UI overlay]
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```
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**Implementation:** See `UIGrid::render()` which iterates layers in z_index order, inserting entity rendering at the 0 boundary.
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### Chunk-Based Caching
|
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|
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Large grids are divided into **chunks** (regions of cells). Each chunk maintains its own `sf::RenderTexture` that caches the rendered result.
|
||||
|
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**Key concepts:**
|
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- Chunk size is implementation-defined (currently ~256 cells per dimension)
|
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- Only chunks intersecting the viewport are considered for rendering
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- Each chunk tracks whether its content is "dirty" (needs redraw)
|
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- Static content renders once, then the cached texture is reused
|
||||
|
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**Implementation:** See `UIGrid::renderChunk()` for chunk texture management.
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### Dirty Flag Propagation
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When layer content changes, only affected chunks are marked dirty:
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1. `layer.set(x, y, value)` marks the containing chunk as dirty
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2. On next render, dirty chunks redraw to their RenderTexture
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3. Clean chunks simply blit their cached texture
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|
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This means a 1000x1000 grid with one changing cell redraws only ~1 chunk, not 1,000,000 cells.
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**Implementation:** Dirty flags propagate through `UIGrid::markDirty()` and are checked in `UIGrid::render()`.
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---
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## Render Pipeline Stages
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### Stage 1: Viewport Calculation
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Calculate which chunks and cells are visible based on camera position, zoom, and grid dimensions.
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|
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**Key properties:**
|
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- `center` / `center_x`, `center_y` - Camera position in pixel coordinates (within grid space)
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- `zoom` - Scale factor (1.0 = normal, 2.0 = 2x magnification)
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- `size` - Viewport dimensions in screen pixels
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**Implementation:** Viewport bounds calculated at start of `UIGrid::render()`.
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### Stage 2: Below-Entity Layers
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For each layer with `z_index < 0`, sorted by z_index:
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1. Determine which chunks intersect viewport
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2. For each visible chunk:
|
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- If dirty: redraw layer content to chunk's RenderTexture
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- Draw chunk's cached texture to output
|
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|
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### Stage 3: Entity Rendering
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|
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Entities render at the z=0 boundary:
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1. Iterate entity collection
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2. Cull entities outside viewport bounds
|
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3. Draw visible entity sprites at interpolated positions
|
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|
||||
**Note:** Entity culling is currently O(n). SpatialHash optimization planned in [#115](../../issues/115).
|
||||
|
||||
### Stage 4: Above-Entity Layers
|
||||
|
||||
For each layer with `z_index >= 0`, sorted by z_index:
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- Same chunk-based rendering as Stage 2
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- These layers appear as overlays (fog, highlights, UI elements)
|
||||
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### Stage 5: Final Compositing
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||||
|
||||
All rendered content exists in the grid's output RenderTexture, which is drawn to the window in a single operation.
|
||||
|
||||
---
|
||||
|
||||
## Performance Characteristics
|
||||
|
||||
**Static Grids:**
|
||||
- Near-zero CPU cost after initial render
|
||||
- Cached chunk textures reused frame-to-frame
|
||||
- Only viewport calculation and texture blitting
|
||||
|
||||
**Dynamic Grids:**
|
||||
- Cost proportional to number of dirty chunks
|
||||
- Single-cell changes affect only one chunk
|
||||
- Bulk operations should batch changes before render
|
||||
|
||||
**Large Grids:**
|
||||
- 1000x1000+ grids render efficiently
|
||||
- Only visible chunks processed
|
||||
- Memory scales with grid size (chunk textures)
|
||||
|
||||
**Profiling:** Use `mcrfpy.getMetrics()` or the F3 overlay to see render times. See [[Performance-and-Profiling]].
|
||||
|
||||
---
|
||||
|
||||
## FOV and Perspective System (In Transition)
|
||||
|
||||
**Current Status:** The FOV computation (`compute_fov()`, `is_in_fov()`) works correctly for pathfinding and visibility queries. However, the automatic fog-of-war overlay system is **not currently connected** to the new layer architecture.
|
||||
|
||||
**What works:**
|
||||
- `grid.compute_fov(x, y, radius)` - Computes which cells are visible
|
||||
- `grid.is_in_fov(x, y)` - Queries visibility of a specific cell
|
||||
- Pathfinding uses walkable/transparent properties correctly
|
||||
|
||||
**What's in transition:**
|
||||
- Per-entity perspective (`UIGridPointState`) not yet exposed to Python
|
||||
- Automatic fog overlay rendering disconnected from layer system
|
||||
- Batch FOV data access being designed ([#113 discussion](../../issues/113))
|
||||
|
||||
**Current workaround - Manual fog layer:**
|
||||
|
||||
```python
|
||||
# Create a fog overlay layer (positive z_index = above entities)
|
||||
fog_layer = grid.add_layer("color", z_index=1)
|
||||
|
||||
# After computing FOV, update fog colors
|
||||
grid.compute_fov(player.grid_x, player.grid_y, radius=10)
|
||||
|
||||
for x in range(grid.grid_x):
|
||||
for y in range(grid.grid_y):
|
||||
if not grid.is_in_fov(x, y):
|
||||
# Dim color for non-visible cells
|
||||
fog_layer.set(x, y, mcrfpy.Color(0, 0, 0, 192))
|
||||
else:
|
||||
# Transparent for visible cells
|
||||
fog_layer.set(x, y, mcrfpy.Color(0, 0, 0, 0))
|
||||
```
|
||||
|
||||
**Limitation:** This O(n²) iteration is inefficient for large grids. Batch operations ([#113](../../issues/113)) will address this with patterns like `cells_in_radius()` iterators.
|
||||
|
||||
---
|
||||
|
||||
## Layer Techniques
|
||||
|
||||
### Multiple Overlay Layers
|
||||
|
||||
You can pre-create multiple overlay layers and toggle between them:
|
||||
|
||||
```python
|
||||
# Create several overlay options
|
||||
highlight_layer = grid.add_layer("color", z_index=1)
|
||||
danger_layer = grid.add_layer("color", z_index=2)
|
||||
fog_layer = grid.add_layer("color", z_index=3)
|
||||
|
||||
# Populate each with different data...
|
||||
# highlight_layer shows selected cells
|
||||
# danger_layer shows enemy threat zones
|
||||
# fog_layer shows visibility
|
||||
|
||||
# Toggle visibility to switch which overlay shows
|
||||
def show_danger_zones():
|
||||
highlight_layer.visible = False
|
||||
danger_layer.visible = True
|
||||
fog_layer.visible = False
|
||||
|
||||
def show_fog_of_war():
|
||||
highlight_layer.visible = False
|
||||
danger_layer.visible = False
|
||||
fog_layer.visible = True
|
||||
```
|
||||
|
||||
### Z-Index Reordering
|
||||
|
||||
Change layer order at runtime by modifying z_index:
|
||||
|
||||
```python
|
||||
# Bring a layer to front
|
||||
important_layer.z_index = 100
|
||||
|
||||
# Send a layer behind entities
|
||||
background_layer.z_index = -10
|
||||
```
|
||||
|
||||
**Note:** Changing z_index marks the layer dirty, triggering re-render of affected chunks.
|
||||
|
||||
### Constructor `layers={}` Limitations
|
||||
|
||||
The `layers={}` constructor argument is convenient but limited:
|
||||
|
||||
```python
|
||||
# This creates layers, but ALL get negative z_index (below entities)
|
||||
grid = mcrfpy.Grid(
|
||||
grid_size=(50, 50),
|
||||
layers={"ground": "color", "terrain": "tile", "overlay": "color"}
|
||||
)
|
||||
# Result: ground=-3, terrain=-2, overlay=-1 (all below entities!)
|
||||
```
|
||||
|
||||
**For overlays above entities, use `add_layer()` explicitly:**
|
||||
|
||||
```python
|
||||
grid = mcrfpy.Grid(grid_size=(50, 50), layers={})
|
||||
ground = grid.add_layer("color", z_index=-2)
|
||||
terrain = grid.add_layer("tile", z_index=-1)
|
||||
overlay = grid.add_layer("color", z_index=1) # Above entities!
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Migration from Legacy API
|
||||
|
||||
Prior to the layer system, grids had built-in per-cell rendering via `UIGridPoint` properties. Here's how to recreate that behavior:
|
||||
|
||||
### Legacy Pattern (Pre-November 2025)
|
||||
|
||||
```python
|
||||
# OLD API (no longer works):
|
||||
grid = mcrfpy.Grid(50, 50, 16, 16)
|
||||
cell = grid.at(x, y)
|
||||
cell.tilesprite = 42 # Sprite index
|
||||
cell.color = (255, 0, 0) # Background color
|
||||
```
|
||||
|
||||
### Equivalent Modern Pattern
|
||||
|
||||
```python
|
||||
# NEW API - explicit layers:
|
||||
grid = mcrfpy.Grid(grid_size=(50, 50), pos=(0, 0), size=(400, 400))
|
||||
|
||||
# Grid creates a default TileLayer; access it:
|
||||
tile_layer = grid.layers[0]
|
||||
tile_layer.set(x, y, 42) # Sprite index
|
||||
|
||||
# For background colors, add a ColorLayer behind tiles:
|
||||
color_layer = grid.add_layer("color", z_index=-2) # Behind default tile layer
|
||||
color_layer.set(x, y, mcrfpy.Color(255, 0, 0))
|
||||
```
|
||||
|
||||
### Recreating Old Three-Layer Rendering
|
||||
|
||||
The legacy system rendered: background color → tile sprite → FOV overlay.
|
||||
|
||||
```python
|
||||
# Create grid with no default layers
|
||||
grid = mcrfpy.Grid(
|
||||
grid_size=(50, 50),
|
||||
pos=(100, 100),
|
||||
size=(400, 400),
|
||||
texture=tileset,
|
||||
layers={}
|
||||
)
|
||||
|
||||
# Layer 1: Background colors (z=-2, behind everything)
|
||||
background = grid.add_layer("color", z_index=-2)
|
||||
|
||||
# Layer 2: Tile sprites (z=-1, above background, below entities)
|
||||
tiles = grid.add_layer("tile", z_index=-1, texture=tileset)
|
||||
|
||||
# Layer 3: FOV overlay (z=+1, above entities)
|
||||
fog = grid.add_layer("color", z_index=1)
|
||||
|
||||
# Now populate layers as needed
|
||||
background.fill(mcrfpy.Color(20, 20, 30)) # Dark blue background
|
||||
|
||||
for x in range(50):
|
||||
for y in range(50):
|
||||
tiles.set(x, y, calculate_tile_index(x, y))
|
||||
|
||||
# FOV overlay updated after compute_fov() calls
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Common Issues
|
||||
|
||||
### Issue: Layer Changes Don't Appear
|
||||
|
||||
**Cause:** Layer content changed but chunk not marked dirty.
|
||||
|
||||
**Fix:** Use layer methods (`set()`, `fill()`) which automatically mark dirty. Direct property manipulation may bypass dirty flagging.
|
||||
|
||||
### Issue: Overlay Appears Behind Entities
|
||||
|
||||
**Cause:** Layer z_index is negative.
|
||||
|
||||
**Fix:** Use `z_index >= 0` for overlays:
|
||||
```python
|
||||
overlay = grid.add_layer("color", z_index=1) # Not z_index=-1
|
||||
```
|
||||
|
||||
### Issue: Performance Degrades with Many Changes
|
||||
|
||||
**Cause:** Each `set()` call can mark a chunk dirty; many scattered changes = many chunk redraws.
|
||||
|
||||
**Fix:** Batch logically-related changes. For bulk updates, consider:
|
||||
```python
|
||||
# Less efficient: 10,000 individual calls
|
||||
for x in range(100):
|
||||
for y in range(100):
|
||||
layer.set(x, y, value)
|
||||
|
||||
# More efficient when available: bulk fill
|
||||
layer.fill(mcrfpy.Color(0, 0, 0)) # Single operation
|
||||
```
|
||||
|
||||
Batch operations API ([#113](../../issues/113)) will provide more patterns.
|
||||
|
||||
---
|
||||
|
||||
## API Quick Reference
|
||||
|
||||
**Grid Properties:**
|
||||
- `center`, `center_x`, `center_y` - Camera position (pixels in grid space)
|
||||
- `zoom` - Scale factor
|
||||
- `layers` - List of layer objects, sorted by z_index
|
||||
- `fill_color` - Grid background (behind all layers)
|
||||
|
||||
**Grid Methods:**
|
||||
- `add_layer(type, z_index, texture)` - Create new layer
|
||||
- `remove_layer(layer)` - Remove a layer
|
||||
|
||||
**Layer Properties:**
|
||||
- `z_index` - Render order
|
||||
- `visible` - Show/hide layer
|
||||
- `grid_size` - Dimensions (read-only)
|
||||
|
||||
**Layer Methods:**
|
||||
- `set(x, y, value)` - Set cell (color or sprite index)
|
||||
- `at(x, y)` - Get cell value
|
||||
- `fill(value)` - Fill all cells
|
||||
|
||||
---
|
||||
|
||||
**Navigation:**
|
||||
- [[Grid-System]] - Parent page, layer concepts
|
||||
- [[Grid-TCOD-Integration]] - FOV computation details
|
||||
- [[Performance-and-Profiling]] - Metrics and optimization
|
||||
- [[Entity-Management]] - Entity rendering
|
||||
|
||||
---
|
||||
|
||||
*Last updated: 2025-11-29*
|
||||
Loading…
Reference in New Issue