das-cards

July 22, 2026 · View on GitHub

Vector playing card rendering for daslang + OpenGL. All 52 standard cards, 2 jokers, and 2 card backs rendered as sharp triangle meshes from SVG source — no textures, no rasterization, crisp at any scale.

Based on SVG-cards v4.0.0 (LGPL-2.1).

Install

daspkg install github.com/borisbat/dasCards

Or clone into your project's modules/ directory.

Quick Start

options gen2

require cards/opengl_cards

var renderer : CardRenderer
var gpu_deck : GpuDeck

// During init (OpenGL context must be active):
renderer = create_card_renderer()
gpu_deck <- load_gpu_deck("cards/svg-cards.svg")

// During draw:
let idx = find_card(gpu_deck, "heart_queen")
draw_card(renderer, gpu_deck, idx, x, y, scale, screen_w, screen_h)

API Reference

Types

Type	Description
`CardRenderer`	Holds the compiled shader program
`GpuDeck`	All uploaded card meshes + name index. Fields: `cards`, `names`

Functions

`create_card_renderer() : CardRenderer`

Create the shader program. Call once during init with an active OpenGL context.

`load_gpu_deck(svg_file : string) : GpuDeck`

Parse SVG, tessellate all cards, upload to GPU. Returns a deck with 56 cards sorted alphabetically by name.

`draw_card(renderer, deck, index, x, y, scale, screen_w, screen_h)`

Draw a single card. Position (x, y) is the top-left corner in screen pixels. scale controls card size (0.5 = half size, 1.0 = full SVG size ~167x242 pixels).

Requires GL_BLEND enabled with GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA and a stencil buffer.

`find_card(deck, name) : int`

Find card index by name. Returns -1 if not found.

`card_count(deck) : int`

Number of cards in the deck (56).

`card_size(scale) : float2`

Card dimensions in pixels at the given scale.

`is_playing_card(name) : bool`

True if the name is a standard playing card, joker, or card back.

Card Names

Names follow the pattern {suit}_{rank}:

Suits: club, diamond, heart, spade
Ranks: 1 (ace), 2–10, jack, queen, king

Examples: heart_1, spade_king, diamond_10, club_jack

Special cards: back, alternate-back, joker_black, joker_red

All 56 names sorted alphabetically:

alternate-back    club_7           diamond_4        heart_1          heart_king       spade_4
back              club_8           diamond_5        heart_10         heart_queen      spade_5
club_1            club_9           diamond_6        heart_2          joker_black      spade_6
club_10           club_jack        diamond_7        heart_3          joker_red        spade_7
club_2            club_king        diamond_8        heart_4          spade_1          spade_8
club_3            club_queen       diamond_9        heart_5          spade_10         spade_9
club_4            diamond_1        diamond_10       heart_6          spade_2          spade_jack
club_5            diamond_2        diamond_jack     heart_7          spade_3          spade_king
club_6            diamond_3        diamond_king     heart_8                           spade_queen
                                   diamond_queen    heart_9
                                                    heart_jack

Constants

Constant	Value	Description
`CARD_DOC_WIDTH`	166.575	Card width in SVG units
`CARD_DOC_HEIGHT`	242.14	Card height in SVG units
`CARD_DOC_MIN`	(1.25, 1.25)	SVG document origin offset
`CARD_DOC_MAX`	(167.825, 243.39)	SVG document extent

Modules

Module	Description
`cards/opengl_cards`	Public API — renderer, deck loading, drawing
`cards/card_mesh`	SVG parsing + tessellation → triangle meshes
`cards/svg_path`	SVG path `d` attribute parser + bezier flattener
`cards/earcut`	Polygon triangulation (mapbox/earcut port)
`cards/glyph_path`	Font glyph outlines via stb_truetype

Requirements

daslang with OpenGL, PUGIXML, and stb_truetype modules enabled
OpenGL context with stencil buffer support
cards/svg-cards.svg — included in the package
cards/DejaVuSerif.ttf — included in the package (SIL Open Font License)

License

LGPL-2.1 (matching SVG-cards source asset).