docs/specs/compiler-languages/pbs/5. Manifest, Stdlib, and SDK Resolution Specification.md

@@ -18,7 +18,7 @@ This document defines the normative compile-time model for:
 This document is the authority for how the compiler discovers and loads:
 
 - ordinary project modules,
-- reserved stdlib modules such as `@sdk:gfx`,
+- reserved stdlib modules such as `@sdk:gfx` and `@sdk:composer`,
 - compile-time reserved metadata attached to those reserved modules,
 - interface-only service facades that wrap host surfaces for source ergonomics,
 - and backend-provided compile surfaces consumed by the frontend for symbolic authoring.
@@ -211,6 +211,20 @@ Rules:
 - `Gfx` becomes visible only through `import`.
 - The compiler accepts that import because the selected stdlib environment exposes `@sdk:gfx`.
 
+For sprite composition in stdlib line `1`, the canonical reserved SDK surface is:
+
+```pbs
+import { Composer } from @sdk:composer;
+
+let status: int = Composer.emit_sprite(7, 0, 12, 18, 0, 2, false, false, 1);
+```
+
+Rules:
+
+- `@sdk:composer` is the canonical sprite-composition module in this wave.
+- `@sdk:gfx` remains valid for primitive and overlay-oriented graphics operations.
+- `Gfx.set_sprite` is not part of the active stdlib line `1` contract.
+
 ## 6. Effective Stdlib of the Build
 
 The root project owns the effective stdlib line of the build.
@@ -359,6 +373,26 @@ Rules:
 - It contributes compile-time symbols and metadata.
 - It does not produce executable bytecode by itself.
 
+Another valid reserved stdlib interface module in stdlib line `1` is the sprite-composition surface:
+
+```pbs
+declare host LowComposer {
+  [Host(module = "composer", name = "emit_sprite", version = 1)]
+  [Capability(name = "gfx")]
+  fn emit_sprite(
+    glyph_id: int,
+    palette_id: int,
+    x: int,
+    y: int,
+    layer: int,
+    bank_id: int,
+    flip_x: bool,
+    flip_y: bool,
+    priority: int
+  ) -> int;
+}
+```
+
 ## 10. Compiler Loading of the Stdlib Environment
 
 The compiler loads the stdlib environment from the stdlib line selected by the root project.
@@ -433,7 +467,7 @@ Rules:
 - `declare host` remains reserved to SDK/toolchain-controlled modules.
 - Ordinary user-authored project modules do not declare canonical host bindings directly.
 - User code consumes SDK exports through normal imports.
-- SDK-facing surfaces such as `Gfx.draw_pixel(...)` are resolved by the compiler against the selected stdlib environment.
+- SDK-facing surfaces such as `Gfx.draw_pixel(...)` and `Composer.emit_sprite(...)` are resolved by the compiler against the selected stdlib environment.
 - Canonical host identity comes from reserved host-binding metadata such as `[Host(...)]`, not from the source spelling of the imported owner.
 
 ## 13. Project Publication and Distribution

docs/specs/compiler-languages/pbs/6.2. Host ABI Binding and Loader Resolution Specification.md

@@ -61,7 +61,7 @@ as the normative runtime-facing identity.
 
 The host-binding pipeline is:
 
-1. User code imports SDK surfaces such as `Gfx` from `@sdk:gfx`.
+1. User code imports SDK surfaces such as `Gfx` from `@sdk:gfx` and `Composer` from `@sdk:composer`.
 2. The compiler resolves those surfaces against the selected stdlib line.
 3. The compiler maps each host-backed SDK member to a canonical identity `(module, name, version)`.
 4. The compiler emits those required canonical identities into the PBX `SYSC` table.
@@ -136,6 +136,33 @@ but the PBX-facing declaration is canonical, for example:
 ("gfx", "draw_pixel", 1)
 ```
 
+The same rule applies to sprite composition through the composer domain.
+For example, the PBS-facing declaration:
+
+```pbs
+declare host LowComposer {
+  [Host(module = "composer", name = "emit_sprite", version = 1)]
+  [Capability(name = "gfx")]
+  fn emit_sprite(
+    glyph_id: int,
+    palette_id: int,
+    x: int,
+    y: int,
+    layer: int,
+    bank_id: int,
+    flip_x: bool,
+    flip_y: bool,
+    priority: int
+  ) -> int;
+}
+```
+
+maps to the canonical runtime identity:
+
+```text
+("composer", "emit_sprite", 1)
+```
+
 The same rule applies to the low-level asset surface.
 For example, the PBS-facing declaration:
 
@@ -396,7 +423,7 @@ Diagnostics should identify the failing canonical identity whenever available.
 
 Rules:
 
-- the loader does not resolve source imports such as `@sdk:gfx`,
+- the loader does not resolve source imports such as `@sdk:gfx` or `@sdk:composer`,
 - the loader only consumes canonical host-binding metadata emitted into the PBX,
 - `stdlib` affects the loader indirectly through what the compiler emitted,
 - the loader must not attempt to reconstruct SDK/module semantics from the PBX.

docs/specs/compiler-languages/pbs/8. Stdlib Environment Packaging and Loading Specification.md

@@ -56,6 +56,9 @@ prometeu-compiler/frontends/prometeu-frontend-pbs/
     stdlib/
       1/
         sdk/
+          composer/
+            main.pbs
+            mod.barrel
           gfx/
             main.pbs
             mod.barrel
@@ -75,7 +78,7 @@ Interpretation:
 
 - `stdlib/1` selects stdlib major line `1`,
 - `sdk` and `core` are reserved project spaces,
-- `gfx`, `audio`, `math` are module paths within those reserved spaces,
+- `composer`, `gfx`, `audio`, `math` are module paths within those reserved spaces,
 - `main.pbs` and `mod.barrel` form the interface module contents.
 
 ## 5. Logical Mapping
@@ -85,6 +88,7 @@ The compiler must treat the physical layout as a logical stdlib environment.
 Required mapping:
 
 - `stdlib/<N>/sdk/gfx` -> `@sdk:gfx`
+- `stdlib/<N>/sdk/composer` -> `@sdk:composer`
 - `stdlib/<N>/sdk/asset` -> `@sdk:asset`
 - `stdlib/<N>/sdk/audio` -> `@sdk:audio`
 - `stdlib/<N>/core/math` -> `@core:math`
@@ -94,7 +98,7 @@ Rules:
 
 - physical storage is an implementation detail,
 - logical module identity is authoritative,
-- callers of the resolver should work with logical addresses such as `@sdk:gfx`, not resource paths.
+- callers of the resolver should work with logical addresses such as `@sdk:gfx` and `@sdk:composer`, not resource paths.
 
 ## 6. Module File Convention
 
@@ -145,6 +149,7 @@ Responsibility:
 Minimum operations:
 
 - `resolve(@sdk:gfx)`
+- `resolve(@sdk:composer)`
 - `resolve(@core:math/vector)`
 
 ### 7.3 `StdlibModuleSource`
@@ -219,6 +224,26 @@ declare host LowAssets {
 }
 ```
 
+or:
+
+```pbs
+declare host LowComposer {
+  [Host(module = "composer", name = "emit_sprite", version = 1)]
+  [Capability(name = "gfx")]
+  fn emit_sprite(
+    glyph_id: int,
+    palette_id: int,
+    x: int,
+    y: int,
+    layer: int,
+    bank_id: int,
+    flip_x: bool,
+    flip_y: bool,
+    priority: int
+  ) -> int;
+}
+```
+
 Rules:
 
 - the parser reads the attribute as part of the interface module source,
@@ -226,6 +251,11 @@ Rules:
 - the compiler stores the extracted metadata in its interface graph,
 - the raw attribute surface is not treated as a runtime object,
 - later lowering stages may consume the extracted metadata to produce PBX host-binding declarations.
+- stdlib line `1` MUST expose the sprite-composition interface module at `@sdk:composer`,
+- that module MUST declare `LowComposer` and public service `Composer`,
+- that module MUST use runtime module `composer` and capability `gfx`,
+- that module MUST expose `emit_sprite(glyph_id: int, palette_id: int, x: int, y: int, layer: int, bank_id: int, flip_x: bool, flip_y: bool, priority: int) -> int`,
+- stdlib line `1` MUST NOT expose `Gfx.set_sprite`,
 - stdlib line `1` MUST expose the low-level asset interface module at `@sdk:asset`,
 - that module MUST declare `LowAssets`,
 - that module MUST use runtime module `asset` and capability `asset`,

docs/specs/compiler/18. Standard Library Surface Specification.md

@@ -164,6 +164,20 @@ Rules:
 - PBS symbolic asset references (`Addressable`) are not themselves required to be stdlib-imported modules;
 - backend-owned frontend surface contracts MAY supply symbolic values that later lower into stdlib host-backed APIs.
 
+### 12.1 Current line `1` sprite-composition rule
+
+For stdlib line `1`, sprite composition is owned by `@sdk:composer`, not by `@sdk:gfx`.
+
+Rules:
+
+- `@sdk:composer` MUST expose a low-level host owner `LowComposer`.
+- `@sdk:composer` MUST expose a public service facade `Composer`.
+- `Composer.emit_sprite(...)` MUST lower through canonical host identity `("composer", "emit_sprite", 1)`.
+- `Composer.emit_sprite(...)` MUST return a raw `int` in this wave.
+- `@sdk:gfx` MAY continue to expose primitive and overlay-oriented operations.
+- `@sdk:gfx` MUST NOT expose `set_sprite`.
+- `bind_scene`, `unbind_scene`, and `set_camera` are deferred and are not required members of `@sdk:composer` in this wave.
+
 ## 13. Stdlib Contract Expectations for Builtin MVP
 
 For the current builtin MVP, stdlib should be able to expose at least:

prometeu-compiler/frontends/prometeu-frontend-pbs/src/main/resources/stdlib/1/sdk/composer/main.pbs

@@ -0,0 +1,33 @@
+declare host LowComposer {
+  [Host(module = "composer", name = "emit_sprite", version = 1)]
+  [Capability(name = "gfx")]
+  fn emit_sprite(
+    glyph_id: int,
+    palette_id: int,
+    x: int,
+    y: int,
+    layer: int,
+    bank_id: int,
+    flip_x: bool,
+    flip_y: bool,
+    priority: int
+  ) -> int;
+}
+
+declare service Composer
+{
+    fn emit_sprite(
+        glyph_id: int,
+        palette_id: int,
+        x: int,
+        y: int,
+        layer: int,
+        bank_id: int,
+        flip_x: bool,
+        flip_y: bool,
+        priority: int
+    ) -> int
+    {
+        return LowComposer.emit_sprite(glyph_id, palette_id, x, y, layer, bank_id, flip_x, flip_y, priority);
+    }
+}

prometeu-compiler/frontends/prometeu-frontend-pbs/src/main/resources/stdlib/1/sdk/composer/mod.barrel

@@ -0,0 +1,2 @@
+mod host LowComposer;
+pub service Composer;

prometeu-compiler/frontends/prometeu-frontend-pbs/src/main/resources/stdlib/1/sdk/gfx/main.pbs

@@ -25,21 +25,6 @@ declare host LowGfx {
   [Capability(name = "gfx")]
   fn draw_square(x: int, y: int, w: int, h: int, border_color: Color, fill_color: Color) -> void;
 
-  [Host(module = "gfx", name = "set_sprite", version = 1)]
-  [Capability(name = "gfx")]
-  fn set_sprite(
-    bank_id: int,
-    index: int,
-    x: int,
-    y: int,
-    tile_id: int,
-    palette_id: int,
-    active: bool,
-    flip_x: bool,
-    flip_y: bool,
-    priority: int
-  ) -> int;
-
   [Host(module = "gfx", name = "draw_text", version = 1)]
   [Capability(name = "gfx")]
   fn draw_text(x: int, y: int, message: str, color: Color) -> void;
@@ -81,22 +66,6 @@ declare service Gfx
         LowGfx.draw_square(x, y, w, h, border_color, fill_color);
     }
 
-    fn set_sprite(
-        bank_id: int,
-        index: int,
-        x: int,
-        y: int,
-        tile_id: int,
-        palette_id: int,
-        active: bool,
-        flip_x: bool,
-        flip_y: bool,
-        priority: int
-    ) -> int
-    {
-        return LowGfx.set_sprite(bank_id, index, x, y, tile_id, palette_id, active, flip_x, flip_y, priority);
-    }
-
     fn draw_text(x: int, y: int, message: str, color: Color) -> void
     {
         LowGfx.draw_text(x, y, message, color);

prometeu-compiler/frontends/prometeu-frontend-pbs/src/test/java/p/studio/compiler/pbs/stdlib/InterfaceModuleLoaderTest.java

@@ -84,4 +84,71 @@ class InterfaceModuleLoaderTest {
                 "pub host LowAssets;",
                 fileTable.get(module.barrelFiles().getFirst().fileId()).readUtf8().orElseThrow());
     }
+
+    @Test
+    void shouldLoadComposerStdlibModuleWithPublicServiceBarrel() {
+        final var projectTable = new ProjectTable();
+        final var projectId = projectTable.register(ProjectDescriptor.builder()
+                .name("app")
+                .version("1.0.0")
+                .rootPath(Path.of("/tmp/app"))
+                .sourceRoots(ReadOnlyList.wrap(java.util.List.of(Path.of("/tmp/app/src"))))
+                .build());
+        final var fileTable = new FileTable(1);
+        final var diagnostics = DiagnosticSink.empty();
+        final var moduleSource = new StdlibModuleSource(
+                "sdk",
+                ReadOnlyList.wrap(java.util.List.of("composer")),
+                ReadOnlyList.wrap(java.util.List.of(new StdlibModuleSource.SourceFile(
+                        "main.pbs",
+                        """
+                        declare host LowComposer {
+                          [Host(module = "composer", name = "emit_sprite", version = 1)]
+                          [Capability(name = "gfx")]
+                          fn emit_sprite(
+                            glyph_id: int,
+                            palette_id: int,
+                            x: int,
+                            y: int,
+                            layer: int,
+                            bank_id: int,
+                            flip_x: bool,
+                            flip_y: bool,
+                            priority: int
+                          ) -> int;
+                        }
+
+                        declare service Composer {
+                          fn emit_sprite(
+                            glyph_id: int,
+                            palette_id: int,
+                            x: int,
+                            y: int,
+                            layer: int,
+                            bank_id: int,
+                            flip_x: bool,
+                            flip_y: bool,
+                            priority: int
+                          ) -> int {
+                            return LowComposer.emit_sprite(glyph_id, palette_id, x, y, layer, bank_id, flip_x, flip_y, priority);
+                          }
+                        }
+                        """))),
+                """
+                mod host LowComposer;
+                pub service Composer;
+                """);
+
+        final var module = new InterfaceModuleLoader().load(moduleSource, projectId, fileTable, diagnostics);
+
+        assertTrue(diagnostics.isEmpty(), diagnostics.stream().map(d -> d.getCode() + ":" + d.getMessage()).toList().toString());
+        assertEquals(1, module.sourceFiles().size());
+        assertEquals(1, module.barrelFiles().size());
+        assertEquals(
+                """
+                mod host LowComposer;
+                pub service Composer;
+                """.strip(),
+                fileTable.get(module.barrelFiles().getFirst().fileId()).readUtf8().orElseThrow().strip());
+    }
 }