History, spatial grid and optimizations

CLAUDE.md

@@ -1,5 +1,34 @@
 # CLAUDE.md
 
+## Project: Cartograph
+
+A browser-based world map creation tool (like Wonderdraft/Inkarnate). C99 compiled to WebAssembly via Emscripten.
+
+### Stack
+- **Graphics:** Sokol (WebGPU backend, `SOKOL_WGPU`) — `lib/sokol/`
+- **UI:** Dear ImGui via cimgui — `lib/imgui/`
+- **Math:** cglm (types are C arrays: `vec2` = `float[2]`, `mat4` = `float[4][4]` column-major) — `lib/cglm/`
+- **Shaders:** WGSL in `src/shaders/`, compiled to C headers via `xxd -i` into `src/generated/`
+
+### Build
+- `make` (release) / `make debug` — outputs `app.html`
+- All includes go through `src/api.h` which defines `SOKOL_IMPL`, `SOKOL_WGPU`, and pulls in every library header
+- Include paths: `lib/sokol`, `lib/imgui`, `lib/imgui/imgui`, `lib/util`, `lib/cglm/include`
+
+### Key files
+- `src/main.c` — entry point, sokol init, render loop, input (zoom/pan/drag)
+- `src/api.h` — central include hub, backend defines
+- `src/sprite.h` — sprite batching, texture manager, file import stubs
+- `src/util.h` — `vector_t` (dynamic array) and `mem_pool_t` (free-list pool), both stripe-based
+- `src/rand.h` — xorshift32 PRNG
+
+### Conventions
+- No malloc/free directly — use `ALLOC`/`FREE` macros (wired to smemtrack in main.c)
+- Assert is encouraged for invariant checks
+- Data structures use stripe-based allocation (byte stride per element, not sizeof)
+
+---
+
 **Tradeoff:** These guidelines bias toward caution over speed. For trivial tasks, use judgment.
 
 ## 1. Think Before Coding

README.md

@@ -0,0 +1,63 @@
+# Cartograph
+
+A browser-based world map creation tool inspired by Wonderdraft and Inkarnate. Uses shape-based terrain generation with procedural detail.
+
+## Features (planned)
+
+- **Shapes** — the fundamental building block. Each shape has:
+  - **Height** — additive (raise terrain) or subtractive (lower terrain)
+  - **Biome** — determines the sampled texture applied to the shape
+  - **Intensity** — blending weight of the biome texture
+  - **Roughness** — edge noise amount (voronoi-like jagged edges at maximum)
+- **Shape editing** — select, move, rotate, scale individual shapes
+- **Groups** — combine shapes into groups for batch operations
+- **Shake landmass** — procedurally decompose a shape into a more complex set of shapes
+- **Viewport** — zoom and pan across the map canvas
+
+## Tech stack
+
+| Layer | Library |
+|---|---|
+| Language | C (C99) |
+| Compiler | [Emscripten](https://emscripten.org/) (emcc) → WebAssembly |
+| Graphics | [Sokol](https://github.com/floooh/sokol) with WebGPU backend |
+| UI | [Dear ImGui](https://github.com/ocornut/imgui) via [cimgui](https://github.com/cimgui/cimgui) |
+| Math | [cglm](https://github.com/recp/cglm) |
+| Shaders | WGSL (compiled to C headers via `xxd`) |
+
+## Build
+
+```sh
+# Install dependencies
+./fetch_libs.sh
+
+# Release build
+make
+
+# Debug build
+make debug
+```
+
+Output is `app.html`, served by Emscripten's built-in web server or any static server.
+
+## Project structure
+
+```
+src/
+  main.c          Entry point, sokol init, render loop, input handling
+  api.h           Central include — all library headers and project-wide defines
+  sprite.h        Sprite batching, texture management, file import
+  util.h          Vector (dynamic array) and memory pool data structures
+  rand.h          Xorshift32 PRNG utilities
+  shaders/        WGSL shader sources
+  generated/      xxd-generated C headers from shaders
+lib/
+  sokol/          Sokol single-file headers (gfx, app, glue, log)
+  imgui/          Dear ImGui + cimgui
+  cglm/           C linear math library
+  util/           Sokol utility headers (memtrack, imgui integration)
+```
+
+## License
+
+MIT

fetch_libs.sh

@@ -9,6 +9,7 @@ echo "=== Fetching library dependencies ==="
 mkdir -p "$LIB_DIR/sokol"
 mkdir -p "$LIB_DIR/imgui"
 mkdir -p "$LIB_DIR/util"
+mkdir -p "$LIB_DIR/cglm"
 
 if [ ! -f "$LIB_DIR/sokol/sokol_gfx.h" ]; then
     echo "  > Fetching sokol (pinned to emdawnwebgpu-compatible version)..."
@@ -47,4 +48,15 @@ else
     echo "  > cimgui already present"
 fi
 
+# 4. cglm
+if [ ! -f "$LIB_DIR/cglm/include/cglm/cglm.h" ]; then
+    echo "  > Fetching cglm..."
+    git clone --depth 1 --branch v0.9.6 https://github.com/recp/cglm.git "$LIB_DIR/cglm_tmp"
+    cp -r "$LIB_DIR/cglm_tmp/include" "$LIB_DIR/cglm/"
+    cp -r "$LIB_DIR/cglm_tmp/src" "$LIB_DIR/cglm/"
+    rm -rf "$LIB_DIR/cglm_tmp"
+else
+    echo "  > cglm already present"
+fi
+
 echo "=== Done ==="

makefile

@@ -19,6 +19,7 @@ IMGUI_SOURCES = $(LIB_DIR)/imgui/imgui/imgui.cpp \
                 $(LIB_DIR)/imgui/imgui/imgui_tables.cpp \
                 $(LIB_DIR)/imgui/imgui/imgui_widgets.cpp \
                 $(LIB_DIR)/imgui/cimgui.cpp
+CGLM_SOURCES = $(wildcard $(LIB_DIR)/cglm/src/*.c)
 
 # Dynamic shader processing
 SHADER_FILES = $(wildcard $(SHADER_DIR)/*.wgsl)
@@ -29,7 +30,8 @@ EMCC_FLAGS = --use-port=emdawnwebgpu \
              -sWASM_BIGINT \
              -sALLOW_MEMORY_GROWTH \
              -msimd128 \
-             -sFILESYSTEM=0
+             -sFILESYSTEM=0 \
+             -flto
 
 # Shell template
 SHELL_FILE = shell.html
@@ -38,8 +40,8 @@ SHELL_FILE = shell.html
 all: $(FETCH) $(TARGET)
 
 # Main build target
-$(TARGET): $(SHADER_HEADERS) $(C_SOURCES) $(IMGUI_SOURCES) $(SHELL_FILE)
+$(TARGET): $(SHADER_HEADERS) $(C_SOURCES) $(IMGUI_SOURCES) $(CGLM_SOURCES) $(SHELL_FILE)
-	$(CC) $(C_SOURCES) $(IMGUI_SOURCES) \
+	$(CC) $(C_SOURCES) $(IMGUI_SOURCES) $(CGLM_SOURCES) \
 		-o $(TARGET) \
 		$(EMCC_FLAGS) \
 		-O3 \
@@ -47,6 +49,7 @@ $(TARGET): $(SHADER_HEADERS) $(C_SOURCES) $(IMGUI_SOURCES) $(SHELL_FILE)
 		-I$(LIB_DIR)/imgui \
 		-I$(LIB_DIR)/imgui/imgui \
 		-I$(LIB_DIR)/util \
+		-I$(LIB_DIR)/cglm/include \
 		--shell-file=$(SHELL_FILE)
 
 # Shader header generation
@@ -58,8 +61,8 @@ $(GENERATED_DIR)/%.h: $(SHADER_DIR)/%.wgsl | $(GENERATED_DIR)
 $(GENERATED_DIR):
 	mkdir -p $(GENERATED_DIR)
 
-debug: $(FETCH) $(SHADER_HEADERS) $(C_SOURCES) $(IMGUI_SOURCES) $(SHELL_FILE)
+debug: $(FETCH) $(SHADER_HEADERS) $(C_SOURCES) $(IMGUI_SOURCES) $(CGLM_SOURCES) $(SHELL_FILE)
-	$(CC) $(C_SOURCES) $(IMGUI_SOURCES) \
+	$(CC) $(C_SOURCES) $(IMGUI_SOURCES) $(CGLM_SOURCES) \
 		-o $(TARGET) \
 		$(EMCC_FLAGS) \
 		-g -gsource-map=inline \
@@ -67,6 +70,7 @@ debug: $(FETCH) $(SHADER_HEADERS) $(C_SOURCES) $(IMGUI_SOURCES) $(SHELL_FILE)
 		-I$(LIB_DIR)/imgui \
 		-I$(LIB_DIR)/imgui/imgui \
 		-I$(LIB_DIR)/util \
+		-I$(LIB_DIR)/cglm/include \
 		--shell-file=$(SHELL_FILE)
 
 # Clean build artifacts

src/api.h

@@ -6,6 +6,7 @@
 #define SOKOL_IMPL
 #define SOKOL_WGPU
 #define SOKOL_IMGUI_IMPL
+#define SOKOL_VALIDATE_NON_FATAL
 
 #include "sokol_gfx.h"
 #include "sokol_app.h"
@@ -14,14 +15,24 @@
 #include "cimgui.h"
 #include "sokol_imgui.h"
 #include "sokol_memtrack.h"
+#include "sokol_shape.h"
+
+#define ALLOC(arg) smemtrack_alloc(arg, NULL)
+#define FREE(arg) smemtrack_free(arg, NULL)
+
+#include "cglm/cglm.h"
 
-#include "math.h"
 #include "rand.h"
-#include "util.h"
-#include "sprite.h"
 
 #include "generated/sprite.h"
+#include "generated/shape.h"
 
+#include "util.h"
+#include "shape.h"
+#include "spatial.h"
+#include "history.h"
+
+#include <emscripten.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <math.h>

src/generated/shape.h

@@ -0,0 +1,95 @@
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+};
+unsigned int src_shaders_shape_wgsl_len = 1103;

src/history.h

@@ -0,0 +1,254 @@
+#ifndef HISTORY_H
+#define HISTORY_H
+
+#include "api.h"
+
+// Each property kind we can undo/redo independently
+typedef enum {
+    HIST_POSITION,
+    HIST_SCALE,
+    HIST_ROTATION,
+    HIST_COLOR,
+} hist_prop_t;
+
+// One property change on one shape (old → new)
+typedef struct hist_change_t {
+    int shape_index;
+    hist_prop_t prop;
+    float old_val[4];
+    float new_val[4];
+} hist_change_t;
+
+// A history entry is one or more changes batched together.
+// Single-property edits = 1 change. Whole-selection edits = N changes.
+typedef struct hist_entry_t {
+    hist_change_t *changes;
+    int count;
+} hist_entry_t;
+
+#define HIST_MAX 64
+
+typedef struct history_t {
+    hist_entry_t entries[HIST_MAX];
+    int count;
+    int current; // index of last applied entry, -1 = initial state
+
+    // Pending edit session (one ImGui widget interaction)
+    bool capturing;
+    int pending_shape_idx;
+    hist_prop_t pending_prop;
+    float pending_old[4];
+} history_t;
+
+// -- internal helpers --
+
+/**
+ * Read the current value of a single property from a shape.
+ *
+ * @param s     shape to read from
+ * @param prop  which property (HIST_POSITION, HIST_SCALE, etc.)
+ * @param out   receives the value, zero-padded to 4 floats
+ */
+static void hist_read_prop(shape_t *s, hist_prop_t prop, float out[4]) {
+    memset(out, 0, sizeof(float[4]));
+    switch (prop) {
+        case HIST_POSITION: out[0] = s->cx; out[1] = s->cy; break;
+        case HIST_SCALE:    out[0] = s->sx; out[1] = s->sy; break;
+        case HIST_ROTATION: out[0] = s->rotation; break;
+        case HIST_COLOR:    memcpy(out, s->uniform.base_color, sizeof(float[4])); break;
+    }
+}
+
+/**
+ * Write a value to a single property of a shape. Does NOT regenerate buffers.
+ *
+ * @param s     shape to modify in-place
+ * @param prop  which property to set
+ * @param val   new value (4 floats, zero-padded for smaller properties)
+ */
+static void hist_apply_prop(shape_t *s, hist_prop_t prop, const float val[4]) {
+    switch (prop) {
+        case HIST_POSITION: s->cx = val[0]; s->cy = val[1]; break;
+        case HIST_SCALE:    s->sx = val[0]; s->sy = val[1]; break;
+        case HIST_ROTATION: s->rotation = val[0]; break;
+        case HIST_COLOR:    memcpy(s->uniform.base_color, val, sizeof(float[4])); break;
+    }
+}
+
+// -- history API --
+
+/**
+ * Zero-initialize the history stack. Call once during app init.
+ *
+ * @param h  history to initialize
+ */
+static void history_init(history_t *h) {
+    memset(h, 0, sizeof(*h));
+    h->current = -1;
+}
+
+/**
+ * Free all heap memory held by the history stack. Call during app shutdown.
+ *
+ * @param h  history to destroy
+ */
+static void history_destroy(history_t *h) {
+    for (int i = 0; i < h->count; i++) {
+        if (h->entries[i].changes) FREE(h->entries[i].changes);
+    }
+    memset(h, 0, sizeof(*h));
+    h->current = -1;
+}
+
+/**
+ * Push a completed entry onto the stack, discarding any redo branch.
+ * Takes ownership of entry.changes (must be heap-allocated with ALLOC).
+ * Used internally by begin_edit/end_edit, or directly for batch edits.
+ *
+ * @param h      history stack
+ * @param entry  entry to push (changes array is consumed, not copied)
+ */
+static void history_push_entry(history_t *h, hist_entry_t entry) {
+    while (h->count > h->current + 1) {
+        h->count--;
+        if (h->entries[h->count].changes) {
+            FREE(h->entries[h->count].changes);
+            h->entries[h->count].changes = NULL;
+        }
+    }
+
+    if (h->count >= HIST_MAX) {
+        if (h->entries[0].changes) FREE(h->entries[0].changes);
+        memmove(&h->entries[0], &h->entries[1],
+                (h->count - 1) * sizeof(hist_entry_t));
+        h->count--;
+        h->current--;
+    }
+
+    h->entries[h->count] = entry;
+    h->count++;
+    h->current = h->count - 1;
+}
+
+/**
+ * Begin capturing an edit session. Snapshots the current value of one property.
+ * If a prior session is still open (e.g. user switched widgets in the same frame),
+ * it is finalized and pushed first.
+ * Call when igIsItemActivated() is true after an ImGui widget.
+ *
+ * @param h         history stack
+ * @param shapes    the shapes vector (used to read current values)
+ * @param shape_idx index of the shape being edited
+ * @param prop      which property is about to change
+ */
+static void history_begin_edit(history_t *h, vector_t *shapes,
+                               int shape_idx, hist_prop_t prop) {
+    if (h->capturing) {
+        shape_t *s = (shape_t*) vec_get(shapes, h->pending_shape_idx);
+        float new_val[4];
+        hist_read_prop(s, h->pending_prop, new_val);
+        if (memcmp(h->pending_old, new_val, sizeof(float[4])) != 0) {
+            hist_change_t change = {
+                .shape_index = h->pending_shape_idx,
+                .prop = h->pending_prop,
+            };
+            memcpy(change.old_val, h->pending_old, sizeof(float[4]));
+            memcpy(change.new_val, new_val, sizeof(float[4]));
+            hist_entry_t entry = { .changes = NULL, .count = 1 };
+            entry.changes = (hist_change_t*) ALLOC(sizeof(hist_change_t));
+            *entry.changes = change;
+            history_push_entry(h, entry);
+        }
+        h->capturing = false;
+    }
+
+    h->capturing = true;
+    h->pending_shape_idx = shape_idx;
+    h->pending_prop = prop;
+    shape_t *s = (shape_t*) vec_get(shapes, shape_idx);
+    hist_read_prop(s, prop, h->pending_old);
+}
+
+/**
+ * End the current edit session and push an entry if the value changed.
+ * Safe to call when no session is active (no-op).
+ * Call when igIsAnyItemActive() transitions from true to false.
+ *
+ * @param h      history stack
+ * @param shapes the shapes vector (used to read final values)
+ */
+static void history_end_edit(history_t *h, vector_t *shapes) {
+    if (!h->capturing) return;
+
+    shape_t *s = (shape_t*) vec_get(shapes, h->pending_shape_idx);
+    float new_val[4];
+    hist_read_prop(s, h->pending_prop, new_val);
+
+    if (memcmp(h->pending_old, new_val, sizeof(float[4])) != 0) {
+        hist_change_t change = {
+            .shape_index = h->pending_shape_idx,
+            .prop = h->pending_prop,
+        };
+        memcpy(change.old_val, h->pending_old, sizeof(float[4]));
+        memcpy(change.new_val, new_val, sizeof(float[4]));
+        hist_entry_t entry = { .changes = NULL, .count = 1 };
+        entry.changes = (hist_change_t*) ALLOC(sizeof(hist_change_t));
+        *entry.changes = change;
+        history_push_entry(h, entry);
+    }
+    h->capturing = false;
+}
+
+/**
+ * Apply every change in an entry to the shapes vector and regenerate buffers.
+ *
+ * @param entry   the history entry to apply
+ * @param shapes  the shapes vector to modify
+ * @param forward true to use new_val (redo), false to use old_val (undo)
+ */
+static void history_apply_entry(hist_entry_t *entry, vector_t *shapes, bool forward) {
+    for (int i = 0; i < entry->count; i++) {
+        hist_change_t *c = &entry->changes[i];
+        if (c->shape_index >= shapes->count) continue;
+        shape_t *s = (shape_t*) vec_get(shapes, c->shape_index);
+        hist_apply_prop(s, c->prop, forward ? c->new_val : c->old_val);
+        shape_regenerate(s);
+        shape_set_state(s, s->hovered, s->selected);
+    }
+}
+
+/**
+ * Undo the most recent history entry.
+ *
+ * @param h              history stack
+ * @param shapes         the shapes vector to revert
+ * @param selected_count out-parameter for updated selection count (currently passed through)
+ * @return               true if state was changed, false if nothing to undo
+ */
+static bool history_undo(history_t *h, vector_t *shapes, int *selected_count) {
+    if (h->current < 0) return false;
+
+    history_apply_entry(&h->entries[h->current], shapes, false);
+    h->current--;
+    (void)selected_count;
+    return true;
+}
+
+/**
+ * Redo the next history entry.
+ *
+ * @param h              history stack
+ * @param shapes         the shapes vector to advance
+ * @param selected_count out-parameter (currently passed through)
+ * @return               true if state was changed, false if nothing to redo
+ */
+static bool history_redo(history_t *h, vector_t *shapes, int *selected_count) {
+    if (h->current + 1 >= h->count) return false;
+
+    h->current++;
+    history_apply_entry(&h->entries[h->current], shapes, true);
+    (void)selected_count;
+    return true;
+}
+
+#endif

src/math.h

@@ -1,49 +0,0 @@
-#ifndef MATH_IMPL_H
-#define MATH_IMPL_H
-
-#include "api.h"
-
-#define PI 3.14159265358979323846
-#define PI32 3.14159265359f
-
-typedef struct vec2f {
-    float x, y;
-}  vec2f;
-typedef struct vec3f {
-    float x, y, z;
-}  vec3f;
-typedef struct vec4f {
-    float x, y, z, w;
-}  vec4f;
-
-typedef struct vec2u {
-    uint32_t x, y;
-}  vec2u;
-typedef struct vec3u {
-    uint32_t x, y, z;
-}  vec3u;
-typedef struct vec4u {
-    uint32_t x, y, z, w;
-}  vec4u;
-
-typedef struct vec2 {
-    int32_t x, y;
-}  vec2;
-typedef struct vec3 {
-    int32_t x, y, z;
-}  vec3;
-typedef struct vec4 {
-    int32_t x, y, z, w;
-}  vec4;
-
-typedef struct mat4x4f {
-    float e[4][4];
-} mat4x4f;
-typedef struct mat4x4u {
-    uint32_t e[4][4];
-} mat4x4u;
-typedef union mat4x4 {
-    int32_t e[4][4];
-} mat4x4;
-
-#endif

src/rand.h

@@ -14,6 +14,11 @@ static float next_float(void);
 static float next_float_max(float max);
 static float next_float_minmax(float min, float max);
 
+/**
+ * Xorshift32 PRNG core. Advances the global seed and returns the new value.
+ *
+ * @return  pseudo-random 32-bit integer
+ */
 static uint32_t xorshift32(void)
 {
     seed ^= seed<<13;
@@ -21,6 +26,12 @@ static uint32_t xorshift32(void)
     seed ^= seed<<5;
     return seed;
 }
+/**
+ * Seed the global PRNG state. Zero is ignored (caller should pass a non-zero
+ * seed). Runs the generator once after seeding to mix the state.
+ *
+ * @param _seed  non-zero 32-bit seed value
+ */
 static void rand_seed(uint32_t _seed)
 {
     if(_seed == 0)
@@ -29,34 +40,64 @@ static void rand_seed(uint32_t _seed)
     seed = _seed;
     xorshift32();
 }
-// PRNG [0-UINT32_MAX]
+/**
+ * Return a random integer in [0, UINT32_MAX].
+ *
+ * @return  pseudo-random 32-bit integer
+ */
 static uint32_t next_int(void)
 {
     return xorshift32();
 }
-// PRNG [0-max]
+/**
+ * Return a random integer in [0, max].
+ *
+ * @param max  inclusive upper bound
+ * @return     pseudo-random integer
+ */
 static uint32_t next_int_max(uint32_t max)
 {
     return (uint32_t) floorf(xorshift32() / (float) UINT32_MAX * max);
 }
-// PRNG [min-max]
+/**
+ * Return a random integer in [min, max].
+ *
+ * @param min  inclusive lower bound
+ * @param max  inclusive upper bound
+ * @return     pseudo-random integer
+ */
 static uint32_t next_int_minmax(uint32_t min, uint32_t max)
 {
     const float x = (float) xorshift32() / UINT32_MAX;
     //(1.0f - Time) * A + Time * B
     return (1.0f - x) * min + x * max;
 }
-// PRNG [0-1]
+/**
+ * Return a random float in [0, 1].
+ *
+ * @return  pseudo-random float
+ */
 static float next_float(void)
 {
     return (float) xorshift32() / UINT32_MAX;
 }
-// PRNG [0-max]
+/**
+ * Return a random float in [0, max].
+ *
+ * @param max  inclusive upper bound
+ * @return     pseudo-random float
+ */
 static float next_float_max(float max)
 {
     return (float) xorshift32() / UINT32_MAX * max;
 }
-// PRNG [min-max]
+/**
+ * Return a random float in [min, max].
+ *
+ * @param min  inclusive lower bound
+ * @param max  inclusive upper bound
+ * @return     pseudo-random float
+ */
 static float next_float_minmax(float min, float max)
 {
     const float x = (float) xorshift32() / UINT32_MAX;

src/shaders/shape.wgsl

@@ -0,0 +1,45 @@
+struct VsUniform {
+    mvp: mat4x4f,
+};
+
+struct ShapeUniform {
+    transform: mat4x4f,
+    base_color: vec4f,
+    state: u32,
+};
+
+struct VsIn {
+    @location(0) position: vec2f,
+};
+
+struct Vs2Fs {
+    @builtin(position) pos: vec4f,
+    @location(0) @interpolate(linear) color: vec4f,
+};
+
+struct FsOut {
+    @location(0) color: vec4f,
+};
+
+@binding(0) @group(0) var<uniform> vs_uniforms: VsUniform;
+@binding(1) @group(0) var<uniform> shape_uniform: ShapeUniform;
+
+@vertex fn vs_main(input: VsIn) -> Vs2Fs {
+    var output: Vs2Fs;
+    let world_pos = vec4f(input.position.x, input.position.y, 0.0, 1.0) * shape_uniform.transform;
+    output.pos = world_pos * vs_uniforms.mvp;
+    if (shape_uniform.state == 2u) {
+        output.color = vec4f(1.0, 0.84, 0.0, 1.0);
+    } else if (shape_uniform.state == 1u) {
+        output.color = clamp(shape_uniform.base_color * 1.5, vec4f(0.0), vec4f(1.0));
+    } else {
+        output.color = shape_uniform.base_color;
+    }
+    return output;
+}
+
+@fragment fn fs_main(input: Vs2Fs) -> FsOut {
+    var output: FsOut;
+    output.color = input.color;
+    return output;
+}

src/shape.h

@@ -0,0 +1,433 @@
+#ifndef SHAPE_H
+#define SHAPE_H
+
+#include "api.h"
+
+typedef struct shape_vertex_t {
+    float x, y;
+} shape_vertex_t;
+
+typedef struct shape_uniform_t {
+    mat4 transform;
+    float base_color[4];
+    uint32_t state;
+    uint8_t _pad[12];
+} shape_uniform_t;
+
+typedef enum shape_kind_t {
+    SHAPE_CIRCLE,
+    SHAPE_STAR,
+} shape_kind_t;
+
+typedef struct shape_t {
+    shape_vertex_t *verts;
+    uint16_t *indices;
+    uint32_t num_indices;
+    uint32_t num_verts;
+    sg_buffer vbuf;
+    sg_buffer ibuf;
+    shape_uniform_t uniform;
+    bool hovered;
+    bool selected;
+
+    shape_kind_t kind;
+    float cx, cy;
+    float sx, sy;
+    float rotation;
+    int star_points;
+    float star_inner_ratio;
+    int last_update_frame;
+} shape_t;
+
+#define SHAPE_HOVER_PX 6.0f
+
+static sg_pipeline shape_pipeline;
+static sg_pipeline overlay_pipeline;
+static sg_shader shape_shader;
+static int g_shape_frame_id;
+
+static void shape_begin_frame(void)
+{
+    g_shape_frame_id++;
+}
+
+/**
+ * Create the shape shader, shape pipeline (line strip), and overlay pipeline
+ * (triangles). Call once during app init before drawing any shapes.
+ */
+static void shape_init_pipeline(void)
+{
+    shape_shader = sg_make_shader(&(sg_shader_desc) {
+        .vertex_func = {
+            .source = (const char*) src_shaders_shape_wgsl,
+            .entry = "vs_main",
+        },
+        .fragment_func = {
+            .source = (const char*) src_shaders_shape_wgsl,
+            .entry = "fs_main",
+        },
+        .uniform_blocks = {
+            [0] = {
+                .size = sizeof(mat4),
+                .stage = SG_SHADERSTAGE_VERTEX,
+                .wgsl_group0_binding_n = 0,
+            },
+            [1] = {
+                .size = sizeof(shape_uniform_t),
+                .stage = SG_SHADERSTAGE_VERTEX,
+                .wgsl_group0_binding_n = 1,
+            },
+        },
+        .attrs = {
+            [0] = { .base_type = SG_SHADERATTRBASETYPE_FLOAT },
+        },
+        .label = "Shape shader",
+    });
+
+    shape_pipeline = sg_make_pipeline(&(sg_pipeline_desc) {
+        .shader = shape_shader,
+        .index_type = SG_INDEXTYPE_UINT16,
+        .primitive_type = SG_PRIMITIVETYPE_LINE_STRIP,
+        .layout.attrs = {
+            [0].format = SG_VERTEXFORMAT_FLOAT2,
+        },
+        .label = "Shape pipeline",
+    });
+
+    overlay_pipeline = sg_make_pipeline(&(sg_pipeline_desc) {
+        .shader = shape_shader,
+        .index_type = SG_INDEXTYPE_UINT16,
+        .primitive_type = SG_PRIMITIVETYPE_TRIANGLES,
+        .layout.attrs = {
+            [0].format = SG_VERTEXFORMAT_FLOAT2,
+        },
+        .label = "Overlay pipeline",
+    });
+}
+
+/**
+ * Destroy the shape shader and both pipelines. Call during app shutdown.
+ */
+static void shape_shutdown_pipeline(void)
+{
+    sg_destroy_pipeline(shape_pipeline);
+    sg_destroy_pipeline(overlay_pipeline);
+    sg_destroy_shader(shape_shader);
+}
+
+/**
+ * Return the number of line segments for a circle of the given radius.
+ * Clamped to [8, 128]; scales roughly with circumference.
+ *
+ * @param r  circle radius in world units
+ * @return   segment count
+ */
+static int shape_calc_segments(float r)
+{
+    int n = (int)(fabsf(r) * 0.5f) + 16;
+    if (n < 8) n = 8;
+    if (n > 128) n = 128;
+    return n;
+}
+
+/**
+ * Set default state for a newly created shape: identity transform, base color,
+ * not hovered, not selected.
+ *
+ * @param s      shape to initialize
+ * @param color  RGBA base color (copied)
+ */
+static void shape_init_common(shape_t *s, const float color[4])
+{
+    s->hovered = false;
+    s->selected = false;
+    memcpy(s->uniform.base_color, color, sizeof(float[4]));
+    s->uniform.state = 0;
+    memset(s->uniform._pad, 0, sizeof(s->uniform._pad));
+}
+
+/**
+ * Build the per-shape transform matrix from cx, cy, rotation.
+ * Uses R(-angle) so the shader's row-vector convention matches the existing
+ * world-space vertex computation.
+ */
+static void shape_build_transform(shape_t *s)
+{
+    mat4 T, R, S, RS;
+    glm_translate_make(T, (vec3){s->cx, s->cy, 0.0f});
+    glm_rotate_make(R, -s->rotation, (vec3){0.0f, 0.0f, 1.0f});
+    glm_scale_make(S, (vec3){s->sx, s->sy, 1.0f});
+    glm_mat4_mul(R, S, RS);
+    glm_mat4_mul(T, RS, s->uniform.transform);
+}
+
+/**
+ * Create GPU vertex and index buffers from the shape's current verts/indices.
+ *
+ * @param s  shape (must have verts and indices allocated)
+ */
+static void shape_make_buffers(shape_t *s)
+{
+    s->vbuf = sg_make_buffer(&(sg_buffer_desc) {
+        .size = s->num_indices * sizeof(shape_vertex_t),
+        .usage = { .stream_update = true },
+        .label = "Shape vertices",
+    });
+    sg_update_buffer(s->vbuf, &(sg_range){s->verts, s->num_indices * sizeof(shape_vertex_t)});
+    s->ibuf = sg_make_buffer(&(sg_buffer_desc) {
+        .usage = { .index_buffer = true },
+        .data = { s->indices, s->num_indices * sizeof(uint16_t) },
+        .label = "Shape indices",
+    });
+}
+
+/**
+ * Destroy GPU buffers and free vertex/index arrays for a single shape.
+ *
+ * @param s  shape to tear down
+ */
+static void shape_shutdown(shape_t *s)
+{
+    sg_destroy_buffer(s->vbuf);
+    sg_destroy_buffer(s->ibuf);
+    FREE(s->verts);
+    FREE(s->indices);
+}
+
+/**
+ * Rebuild vertex and index data from the shape's current parameters (position,
+ * scale, rotation, kind), then recreate GPU buffers. Call after any parameter
+ * change.
+ *
+ * @param s  shape to regenerate
+ */
+static void shape_regenerate(shape_t *s)
+{
+    int n, count;
+    if (s->kind == SHAPE_CIRCLE) {
+        int segs = shape_calc_segments(s->sx);
+        n = segs;
+        count = segs + 1;
+    } else {
+        n = s->star_points * 2;
+        count = n + 1;
+    }
+
+    bool resized = ((uint32_t)count != s->num_indices);
+    if (resized) {
+        sg_destroy_buffer(s->vbuf);
+        sg_destroy_buffer(s->ibuf);
+        FREE(s->verts);
+        FREE(s->indices);
+        s->verts = (shape_vertex_t*) ALLOC(count * sizeof(shape_vertex_t));
+        s->indices = (uint16_t*) ALLOC(count * sizeof(uint16_t));
+    }
+
+    if (s->kind == SHAPE_CIRCLE) {
+        int segs = n;
+        for (int i = 0; i < segs; i++) {
+            float a = (float)i / (float)segs * 2.0f * GLM_PIf - GLM_PI_2f;
+            s->verts[i] = (shape_vertex_t) { cosf(a), sinf(a) };
+        }
+        s->verts[segs] = s->verts[0];
+    } else {
+        for (int i = 0; i < n; i++) {
+            float a = (float)i / (float)n * 2.0f * GLM_PIf - GLM_PI_2f;
+            float r = (i & 1) ? s->star_inner_ratio : 1.0f;
+            s->verts[i] = (shape_vertex_t) { cosf(a) * r, sinf(a) * r };
+        }
+        s->verts[n] = s->verts[0];
+    }
+
+    s->num_indices = (uint32_t)count;
+    s->num_verts = (uint32_t)n;
+    for (int i = 0; i <= n; i++) s->indices[i] = (uint16_t)i;
+
+    shape_build_transform(s);
+
+    if (resized) {
+        shape_make_buffers(s);
+        s->last_update_frame = g_shape_frame_id;
+    } else if (s->last_update_frame != g_shape_frame_id) {
+        sg_update_buffer(s->vbuf, &(sg_range){s->verts, (size_t)count * sizeof(shape_vertex_t)});
+        s->last_update_frame = g_shape_frame_id;
+    }
+}
+
+/**
+ * Update hovered/selected flags and the shader uniform state.
+ * State is 0=normal, 1=hovered (brightened), 2=selected (green).
+ *
+ * @param s         shape to update
+ * @param hovered   true if cursor is over the shape
+ * @param selected  true if shape is in the selection set
+ */
+static void shape_set_state(shape_t *s, bool hovered, bool selected)
+{
+    s->hovered = hovered;
+    s->selected = selected;
+    s->uniform.state = selected ? 2u : (hovered ? 1u : 0u);
+}
+
+/**
+ * Ray-casting point-in-polygon test. Handles arbitrary non-self-intersecting
+ * polygons.
+ *
+ * @param px     point X in world space
+ * @param py     point Y in world space
+ * @param verts  polygon vertices
+ * @param n      vertex count
+ * @return       true if the point is inside the polygon
+ */
+static bool point_in_polygon(float px, float py, shape_vertex_t *verts, uint32_t n)
+{
+    bool inside = false;
+    for (uint32_t i = 0, j = n - 1; i < n; j = i++) {
+        float xi = verts[i].x, yi = verts[i].y;
+        float xj = verts[j].x, yj = verts[j].y;
+        if ((yi > py) != (yj > py) && px < (xj - xi) * (py - yi) / (yj - yi) + xi)
+            inside = !inside;
+    }
+    return inside;
+}
+
+/**
+ * Test whether a world-space point hits this shape. Transforms the query
+ * to local space (verts are now stored relative to origin), then tests
+ * polygon containment and edge proximity.
+ *
+ * @param s          shape to test
+ * @param wx         point X in world space
+ * @param wy         point Y in world space
+ * @param world_tol  hit tolerance in world units
+ * @return           true if the point hits the shape
+ */
+static bool shape_hit_test(shape_t *s, float wx, float wy, float world_tol)
+{
+    float sc = cosf(s->rotation), ss = sinf(s->rotation);
+    float dx = wx - s->cx, dy = wy - s->cy;
+    float lx = (dx * sc + dy * ss) / s->sx;
+    float ly = (-dx * ss + dy * sc) / s->sy;
+    float min_scale = fminf(fabsf(s->sx), fabsf(s->sy));
+    float local_tol = world_tol / (min_scale > 0.0001f ? min_scale : 1.0f);
+    float tol_sq = local_tol * local_tol;
+
+    if (point_in_polygon(lx, ly, s->verts, s->num_verts))
+        return true;
+
+    for (uint32_t i = 0, j = s->num_verts - 1; i < s->num_verts; j = i++) {
+        float ax = s->verts[i].x, ay = s->verts[i].y;
+        float bx = s->verts[j].x, by = s->verts[j].y;
+        float abx = bx - ax, aby = by - ay;
+        float len_sq = abx * abx + aby * aby;
+        if (len_sq < 0.0001f) continue;
+        float t = ((lx - ax) * abx + (ly - ay) * aby) / len_sq;
+        t = fmaxf(0.0f, fminf(1.0f, t));
+        float cx = ax + t * abx, cy = ay + t * aby;
+        float ddx = lx - cx, ddy = ly - cy;
+        if (ddx * ddx + ddy * ddy <= tol_sq) return true;
+    }
+    return false;
+}
+
+/**
+ * Issue a draw call for this shape using the shape line-strip pipeline.
+ *
+ * @param s    shape to draw
+ * @param mvp  model-view-projection matrix (from compute_mvp)
+ */
+static void shape_draw(shape_t *s, const mat4 *mvp)
+{
+    sg_apply_uniforms(0, &SG_RANGE(*mvp));
+    sg_apply_uniforms(1, &SG_RANGE(s->uniform));
+    sg_apply_bindings(&(sg_bindings) {
+        .vertex_buffers[0] = s->vbuf,
+        .index_buffer = s->ibuf,
+    });
+    sg_draw(0, s->num_indices, 1);
+}
+
+/**
+ * Create a circle shape (returned by value). Allocates verts/indices and GPU
+ * buffers. The number of line segments adapts to radius.
+ *
+ * @param x      center X in world space
+ * @param y      center Y in world space
+ * @param r      radius in world units
+ * @param color  RGBA base color
+ * @return       fully initialized shape_t
+ */
+static shape_t shape_circle(float x, float y, float r, const float color[4])
+{
+    shape_t s;
+    s.kind = SHAPE_CIRCLE;
+    s.cx = x; s.cy = y;
+    s.sx = r; s.sy = r;
+    s.rotation = 0.0f;
+
+    int segs = shape_calc_segments(r);
+    int count = segs + 1;
+    s.verts = (shape_vertex_t*) ALLOC(count * sizeof(shape_vertex_t));
+    s.indices = (uint16_t*) ALLOC(count * sizeof(uint16_t));
+
+    for (int i = 0; i < segs; i++) {
+        float a = (float)i / (float)segs * 2.0f * GLM_PIf - GLM_PI_2f;
+        s.verts[i] = (shape_vertex_t) { cosf(a), sinf(a) };
+    }
+    s.verts[segs] = s.verts[0];
+    for (int i = 0; i <= segs; i++) s.indices[i] = (uint16_t)i;
+    s.num_indices = (uint32_t)count;
+    s.num_verts = (uint32_t)segs;
+
+    shape_init_common(&s, color);
+    shape_build_transform(&s);
+    shape_make_buffers(&s);
+    return s;
+}
+
+/**
+ * Create a star shape (returned by value). Alternates between outer_r and
+ * inner_r at each vertex, producing a star with the given number of points.
+ * Allocates verts/indices and GPU buffers.
+ *
+ * @param x        center X in world space
+ * @param y        center Y in world space
+ * @param outer_r  outer radius in world units
+ * @param inner_r  inner radius in world units
+ * @param points   number of star points
+ * @param color    RGBA base color
+ * @return         fully initialized shape_t
+ */
+static shape_t shape_star(float x, float y, float outer_r, float inner_r,
+                           int points, const float color[4])
+{
+    shape_t s;
+    s.kind = SHAPE_STAR;
+    s.cx = x; s.cy = y;
+    s.sx = outer_r; s.sy = outer_r;
+    s.rotation = 0.0f;
+    s.star_points = points;
+    s.star_inner_ratio = inner_r / outer_r;
+
+    int n = points * 2;
+    int count = n + 1;
+    s.verts = (shape_vertex_t*) ALLOC(count * sizeof(shape_vertex_t));
+    s.indices = (uint16_t*) ALLOC(count * sizeof(uint16_t));
+
+    for (int i = 0; i < n; i++) {
+        float a = (float)i / (float)n * 2.0f * GLM_PIf - GLM_PI_2f;
+        float r = (i & 1) ? s.star_inner_ratio : 1.0f;
+        s.verts[i] = (shape_vertex_t) { cosf(a) * r, sinf(a) * r };
+    }
+    s.verts[n] = s.verts[0];
+    for (int i = 0; i <= n; i++) s.indices[i] = (uint16_t)i;
+    s.num_indices = (uint32_t)count;
+    s.num_verts = (uint32_t)n;
+
+    shape_init_common(&s, color);
+    shape_build_transform(&s);
+    shape_make_buffers(&s);
+    return s;
+}
+
+#endif

src/spatial.h

@@ -0,0 +1,233 @@
+#ifndef SPATIAL_H
+#define SPATIAL_H
+
+#include "api.h"
+
+// Tunable constants
+#define SPATIAL_CELL_SIZE    250.0f
+#define SPATIAL_HASH_BITS    8
+#define SPATIAL_HASH_SIZE    (1 << SPATIAL_HASH_BITS)
+#define SPATIAL_QUERY_RANGE  1
+
+typedef struct {
+    int shape_idx;
+    float min_x, min_y, max_x, max_y;
+} spatial_entry_t;
+
+typedef struct {
+    bool occupied;
+    int cx, cy;
+    spatial_entry_t *entries;
+    int count;
+    int capacity;
+} spatial_slot_t;
+
+typedef struct {
+    spatial_slot_t slots[SPATIAL_HASH_SIZE];
+    bool dirty;
+} spatial_grid_t;
+
+static int spatial_hash(int cx, int cy)
+{
+    return (cx * 73856093) ^ (cy * 19349663);
+}
+
+static void spatial_compute_aabb(shape_t *s, float *min_x, float *min_y,
+                                  float *max_x, float *max_y)
+{
+    float cos_r = cosf(s->rotation);
+    float sin_r = sinf(s->rotation);
+    float hx = fabsf(cos_r) * s->sx + fabsf(sin_r) * s->sy;
+    float hy = fabsf(sin_r) * s->sx + fabsf(cos_r) * s->sy;
+    *min_x = s->cx - hx;
+    *min_y = s->cy - hy;
+    *max_x = s->cx + hx;
+    *max_y = s->cy + hy;
+}
+
+static void spatial_init(spatial_grid_t *grid)
+{
+    memset(grid, 0, sizeof(*grid));
+    grid->dirty = true;
+}
+
+static void spatial_mark_dirty(spatial_grid_t *grid)
+{
+    grid->dirty = true;
+}
+
+static void spatial_destroy(spatial_grid_t *grid)
+{
+    for (int i = 0; i < SPATIAL_HASH_SIZE; i++) {
+        if (grid->slots[i].entries) FREE(grid->slots[i].entries);
+    }
+    memset(grid, 0, sizeof(*grid));
+}
+
+static void spatial_rebuild(spatial_grid_t *grid, vector_t *shapes)
+{
+    if (!grid->dirty) return;
+    grid->dirty = false;
+
+    int n = shapes->count;
+
+    // Phase 0: clear occupied flags
+    for (int i = 0; i < SPATIAL_HASH_SIZE; i++) {
+        grid->slots[i].occupied = false;
+        grid->slots[i].count = 0;
+    }
+
+    if (n == 0) return;
+
+    // Phase 1: count shapes per cell
+    for (int i = 0; i < n; i++) {
+        shape_t *s = (shape_t*) vec_get(shapes, i);
+        int ccx = (int) floorf(s->cx / SPATIAL_CELL_SIZE);
+        int ccy = (int) floorf(s->cy / SPATIAL_CELL_SIZE);
+
+        int idx = spatial_hash(ccx, ccy) & (SPATIAL_HASH_SIZE - 1);
+        while (grid->slots[idx].occupied) {
+            if (grid->slots[idx].cx == ccx && grid->slots[idx].cy == ccy) break;
+            idx = (idx + 1) & (SPATIAL_HASH_SIZE - 1);
+        }
+
+        if (!grid->slots[idx].occupied) {
+            grid->slots[idx].occupied = true;
+            grid->slots[idx].cx = ccx;
+            grid->slots[idx].cy = ccy;
+        }
+        grid->slots[idx].count++;
+    }
+
+    // Phase 2: allocate entry arrays based on count
+    for (int i = 0; i < SPATIAL_HASH_SIZE; i++) {
+        if (!grid->slots[i].occupied) continue;
+        if (grid->slots[i].count > grid->slots[i].capacity) {
+            if (grid->slots[i].entries) FREE(grid->slots[i].entries);
+            grid->slots[i].entries = (spatial_entry_t*) ALLOC(
+                (size_t) grid->slots[i].count * sizeof(spatial_entry_t));
+            grid->slots[i].capacity = grid->slots[i].count;
+        }
+        grid->slots[i].count = 0; // reset for fill phase
+    }
+
+    // Phase 3: fill entries
+    for (int i = 0; i < n; i++) {
+        shape_t *s = (shape_t*) vec_get(shapes, i);
+        int ccx = (int) floorf(s->cx / SPATIAL_CELL_SIZE);
+        int ccy = (int) floorf(s->cy / SPATIAL_CELL_SIZE);
+
+        int idx = spatial_hash(ccx, ccy) & (SPATIAL_HASH_SIZE - 1);
+        while (!(grid->slots[idx].occupied &&
+                 grid->slots[idx].cx == ccx && grid->slots[idx].cy == ccy)) {
+            idx = (idx + 1) & (SPATIAL_HASH_SIZE - 1);
+        }
+
+        spatial_entry_t *e = &grid->slots[idx].entries[grid->slots[idx].count++];
+        e->shape_idx = i;
+        spatial_compute_aabb(s, &e->min_x, &e->min_y, &e->max_x, &e->max_y);
+    }
+}
+
+static int spatial_query_point(spatial_grid_t *grid, vector_t *shapes,
+                                float wx, float wy, float world_tol)
+{
+    int ccx = (int) floorf(wx / SPATIAL_CELL_SIZE);
+    int ccy = (int) floorf(wy / SPATIAL_CELL_SIZE);
+
+    for (int dz = -SPATIAL_QUERY_RANGE; dz <= SPATIAL_QUERY_RANGE; dz++) {
+        for (int dw = -SPATIAL_QUERY_RANGE; dw <= SPATIAL_QUERY_RANGE; dw++) {
+            int cell_x = ccx + dz;
+            int cell_y = ccy + dw;
+
+            int idx = spatial_hash(cell_x, cell_y) & (SPATIAL_HASH_SIZE - 1);
+            int probe_start = idx;
+
+            do {
+                if (!grid->slots[idx].occupied) break;
+
+                if (grid->slots[idx].cx == cell_x && grid->slots[idx].cy == cell_y) {
+                    for (int e = 0; e < grid->slots[idx].count; e++) {
+                        spatial_entry_t *entry = &grid->slots[idx].entries[e];
+
+                        if (wx < entry->min_x - world_tol ||
+                            wx > entry->max_x + world_tol ||
+                            wy < entry->min_y - world_tol ||
+                            wy > entry->max_y + world_tol)
+                            continue;
+
+                        shape_t *s = (shape_t*) vec_get(shapes, entry->shape_idx);
+                        if (shape_hit_test(s, wx, wy, world_tol))
+                            return entry->shape_idx;
+                    }
+                    break;
+                }
+
+                idx = (idx + 1) & (SPATIAL_HASH_SIZE - 1);
+            } while (idx != probe_start);
+        }
+    }
+    return -1;
+}
+
+static int spatial_query_rect_select(spatial_grid_t *grid, vector_t *shapes,
+                                      float min_x, float min_y,
+                                      float max_x, float max_y)
+{
+    for (int i = 0; i < shapes->count; i++) {
+        ((shape_t*) vec_get(shapes, i))->selected = false;
+    }
+    int selected_count = 0;
+
+    int min_cx = (int) floorf(min_x / SPATIAL_CELL_SIZE);
+    int min_cy = (int) floorf(min_y / SPATIAL_CELL_SIZE);
+    int max_cx = (int) floorf(max_x / SPATIAL_CELL_SIZE);
+    int max_cy = (int) floorf(max_y / SPATIAL_CELL_SIZE);
+
+    for (int cell_x = min_cx; cell_x <= max_cx; cell_x++) {
+        for (int cell_y = min_cy; cell_y <= max_cy; cell_y++) {
+            int idx = spatial_hash(cell_x, cell_y) & (SPATIAL_HASH_SIZE - 1);
+            int probe_start = idx;
+
+            do {
+                if (!grid->slots[idx].occupied) break;
+
+                if (grid->slots[idx].cx == cell_x && grid->slots[idx].cy == cell_y) {
+                    for (int e = 0; e < grid->slots[idx].count; e++) {
+                        spatial_entry_t *entry = &grid->slots[idx].entries[e];
+
+                        if (entry->max_x < min_x || entry->min_x > max_x ||
+                            entry->max_y < min_y || entry->min_y > max_y)
+                            continue;
+
+                        shape_t *s = (shape_t*) vec_get(shapes, entry->shape_idx);
+                        if (s->selected) continue;
+
+                        bool hit = (s->cx >= min_x && s->cx <= max_x &&
+                                    s->cy >= min_y && s->cy <= max_y);
+                        float sc = cosf(s->rotation), ss = sinf(s->rotation);
+                        for (uint32_t v = 0; !hit && v < s->num_verts; v++) {
+                            float lx = s->verts[v].x * s->sx;
+                            float ly = s->verts[v].y * s->sy;
+                            float wx = s->cx + lx * sc - ly * ss;
+                            float wy = s->cy + lx * ss + ly * sc;
+                            if (wx >= min_x && wx <= max_x &&
+                                wy >= min_y && wy <= max_y)
+                                hit = true;
+                        }
+                        if (hit) {
+                            s->selected = true;
+                            selected_count++;
+                        }
+                    }
+                    break;
+                }
+
+                idx = (idx + 1) & (SPATIAL_HASH_SIZE - 1);
+            } while (idx != probe_start);
+        }
+    }
+    return selected_count;
+}
+
+#endif

src/sprite.h

@@ -1,79 +0,0 @@
-#ifndef SPRITE_H
-#define SPRITE_H
-
-#include "api.h"
-
-#define KB (1024u)
-#define MB (1024u * KB)
-#define GB (1024u * MB)
-#define MAX_FILE_SIZE (10u * MB)
-
-typedef struct texture_t {
-    uint32_t id; //Texture ID
-    sg_bindings binding; //Texture bindings (texture, sampler and buffer)
-    vector_t sprites;
-    bool dirty;
-} texture_t;
-
-typedef struct sprite_t {
-    mat4x4f transform;
-} sprite_t;
-
-typedef struct manager_t {
-    vector_t textures;
-} manager_t;
-
-typedef struct loader_t {
-    uint8_t buffer[MAX_FILE_SIZE];
-} loader_t;
-
-typedef void (*ForEachTexture)(texture_t *texture, void *userdata);
-typedef void (*ForEachSprite)(sprite_t *sprite, void *userdata);
-
-void gs_init(manager_t *manager);
-void gs_shutdown(manager_t *manager);
-void gs_import_file(const sapp_html5_fetch_response *response);
-
-void gs_each_textures(manager_t *manager, ForEachTexture callback, void *userdata);
-void gs_each_sprites(manager_t *manager, ForEachSprite callback, void *userdata);
-
-void gs_init(manager_t *manager)
-{
-    manager->textures = vector_create(sizeof(texture_t));
-}
-void gs_shutdown(manager_t *manager)
-{
-    vector_free(&manager->textures);
-}
-
-void gs_import_file(const sapp_html5_fetch_response *response)
-{
-    const char* filename = sapp_get_dropped_file_path(response->file_index);
-    
-    if(response->succeeded)
-    {
-        
-    }
-    else
-    {
-        //Toast error
-    }
-}
-void gs_each_textures(manager_t *manager, ForEachTexture callback, void *userdata)
-{
-    for(uint32_t i = 0; i < manager->textures.size; i++)
-        callback((texture_t*) manager->textures.data[i], userdata);
-}
-void gs_each_sprites(manager_t *manager, ForEachSprite callback, void *userdata)
-{
-    for(uint32_t i = 0; i < manager->textures.size; i++)
-    {
-        const texture_t* texture = (texture_t*) manager->textures.data[i];
-        for(uint32_t j = 0; j < texture->sprites.size; j++)
-        {
-            callback((sprite_t*) texture->sprites.data[j], userdata);
-        }
-    }
-}
-
-#endif

src/util.h

@@ -1,241 +1,104 @@
 #ifndef UTIL_H
 #define UTIL_H
 
-#include "api.h"
+#include <stdint.h>
-
+#include <string.h>
-/*typedef struct linked_list_t {
-    linked_item_t *first, *last;
-    uint16_t size;
-} linked_list_t;
-
-typedef struct linked_item_t {
-    linked_item_t *next, *prev;
-    void *data;
-} linked_item_t;
-
-typedef void (*linked_list_callback)(void *item);
-
-//Currently, these are the only method required. 
-//Many more could be implemented but this is unnecessary.
-static void l_list_push(linked_list_t *l_list, void *item);
-static void l_list_append(linked_list_t *l_list, void *item);
-static void* l_list_pop(linked_list_t *l_list);
-static void* l_list_unppend(linked_list_t *l_list);
-static void l_list_each(linked_list_t *l_list, linked_list_callback callback);
-
-static inline void l_list_push(linked_list_t *l_list, void *item)
-{
-    linked_item_t l_item = (linked_item_t) { .data = item, .prev = l_list->last, .next = nullptr };
-    
-    if(l_list->first == nullptr)
-        l_list->first = &l_item;
-
-    l_list->last->next = &l_item;
-    l_list->last = &l_item;
-    l_list->size++;
-}
-static inline void l_list_append(linked_list_t *l_list, void *item)
-{
-    linked_item_t l_item = (linked_item_t) { .data = item, .prev = nullptr, .next = l_list->last };
-    
-    if(l_list->last == nullptr)
-        l_list->last = &l_item;
-
-    l_list->first->prev = &l_item;
-    l_list->first = &l_item;
-    l_list->size++;
-}
-static inline void* l_list_pop(linked_list_t *l_list)
-{
-    if(l_list->last == nullptr)
-        return;
-    
-    if(l_list->first == l_list->last)
-        l_list->first = nullptr;
-    
-    linked_item_t *item = l_list->last->prev;
-    l_list->last->prev = nullptr;
-    l_list->last = item;
-    l_list->size--;
-}
-static inline void* l_list_unppend(linked_list_t *l_list)
-{
-    if(l_list->first == nullptr)
-        return;
-    
-    if(l_list->last == l_list->first)
-        l_list->last = nullptr;
-    
-    linked_item_t *item = l_list->first->next;
-    l_list->first->next = nullptr;
-    l_list->first = item;
-    l_list->size--;
-}
-static inline void l_list_each(linked_list_t *l_list, linked_list_callback callback)
-{
-
-}*/
 
 typedef struct vector_t {
-    void **data; //Memory pool
+    uint8_t *data;
-    uint16_t stripe; //Bit per item
+    int count;
-    uint32_t size; //Current amount of items
+    int capacity;
-    uint32_t capacity; //Max capacity
+    int stride;
 } vector_t;
 
-#define MAX_BUCKET_SIZE (0xffffffffu)
+/**
-#define MAX_STRIPE_SIZE (0xffffffu)
+ * Zero-initialize a vector with the given element stride.
-#define FIXED_START (0xfffu)
+ *
-
+ * @param v      vector to initialize
-static vector_t vector_create(uint32_t stripe); //Create a new vector with a default size
+ * @param stride byte size of each element
-static void vector_clear(vector_t *vector);
+ */
-static void vector_free(vector_t *vector);
+static void vec_init(vector_t *v, int stride) {
-
+    memset(v, 0, sizeof(*v));
-static uint32_t vector_length(vector_t *vector);
+    v->stride = stride;
-static void* vector_get(vector_t *vector, uint32_t index);
-static void vector_set(vector_t *vector, uint32_t index, void *data);
-static uint32_t vector_push(vector_t *vector, void *data);
-static sg_range vector_range(vector_t *vector);
-
-static vector_t vector_create(uint32_t stripe)
-{
-    assert(stripe >= sizeof(uint32_t)); 
-    assert(stripe <= MAX_STRIPE_SIZE);
-    assert(FIXED_START * stripe <= MAX_BUCKET_SIZE);
-
-    return (vector_t) {
-        .capacity = FIXED_START,
-        .size = 0,
-        .stripe = stripe,
-        .data = (void**) malloc(FIXED_START * stripe),
-    };
-}
-static void vector_clear(vector_t *vector)
-{
-    vector->size = 0;
-}
-static void vector_free(vector_t *vector)
-{
-    free(vector->data);
 }
 
-static uint32_t vector_length(vector_t *vector)
+/**
-{
+ * Grow the vector's backing array to at least min_capacity elements.
-    return vector->size;
+ * Doubles capacity (starting at 8) or uses min_capacity, whichever is larger.
-}
+ *
-static void* vector_get(vector_t *vector, uint32_t index)
+ * @param v            vector to grow
-{
+ * @param min_capacity minimum element count required
-    assert(index > 0);
+ */
-    assert(index < vector->size);
+static void vec_grow(vector_t *v, int min_capacity) {
-
+    int new_cap = v->capacity ? v->capacity * 2 : 8;
-    return vector->data[index * vector->stripe];
+    if (new_cap < min_capacity) new_cap = min_capacity;
-}
+    uint8_t *new_data = (uint8_t*) ALLOC(new_cap * v->stride);
-static void vector_set(vector_t *vector, uint32_t index, void *data)
+    if (v->data) {
-{
+        memcpy(new_data, v->data, v->count * v->stride);
-    assert(index > 0);
+        FREE(v->data);
-    assert(index < vector->size);
-
-    vector->data[index * vector->stripe] = data;
-}
-static uint32_t vector_push(vector_t *vector, void *data)
-{
-    if(vector->size >= vector->capacity)
-    {
-        vector->capacity *= 2;
-
-        vector->data = (void**) realloc(vector->data, vector->capacity * vector->stripe);
     }
-
+    v->data = new_data;
-    return vector->size++;
+    v->capacity = new_cap;
-}
-static sg_range vector_range(vector_t *vector)
-{
-    return (sg_range) {
-        .ptr = vector->data,
-        .size = vector->size,
-    };
 }
 
-typedef struct mem_pool_t {
+/**
-    void **data; //Memory pool
+ * Append an uninitialized element to the end of the vector. Grows if needed.
-    uint32_t stripe; //Bit per item
+ *
-    uint32_t size; //Current amount of items
+ * @param v  vector to push into
-    uint32_t capacity; //Max capacity
+ * @return   pointer to the new (uninitialized) element
-    uint32_t free; //Linked list of available indices
+ */
-} mem_pool_t;
+static void *vec_push(vector_t *v) {
-
+    if (v->count >= v->capacity) vec_grow(v, v->count + 1);
-static mem_pool_t pool_create_default(uint32_t stripe); //Create a new memory pool with a default size
+    return v->data + (v->count++) * v->stride;
-static mem_pool_t pool_create(uint32_t stripe, uint32_t size); //Create a new memory pool with a default size
-static void pool_clear(mem_pool_t *pool);
-static void pool_free(mem_pool_t *pool);
-
-static const uint32_t pool_add(mem_pool_t *pool); //Request a new free index
-static const void* pool_get(mem_pool_t *pool, uint32_t index); //Get the pointer
-static void pool_remove(mem_pool_t *pool, uint32_t index); //Flag the given index as free
-
-static mem_pool_t pool_create_default(uint32_t stripe)
-{
-    return pool_create(stripe, FIXED_START);
-}
-static mem_pool_t pool_create(uint32_t stripe, uint32_t size)
-{
-    assert(stripe >= sizeof(uint32_t)); 
-    assert(stripe <= MAX_STRIPE_SIZE);
-    assert(size * stripe <= MAX_BUCKET_SIZE);
-
-    return (mem_pool_t) {
-        .capacity = size,
-        .size = 0,
-        .stripe = stripe,
-        .free = UINT32_MAX,
-        .data = (void**) malloc(size * stripe),
-    };
-}
-static void pool_clear(mem_pool_t *pool)
-{
-    pool->size = 0;
-    pool->free = UINT32_MAX;
-}
-static void pool_free(mem_pool_t *pool)
-{
-    free(pool->data);
 }
 
-static const uint32_t pool_add(mem_pool_t *pool)
+/**
-{
+ * Remove the last element from the vector (decrements count, no free).
-    if(pool->free != UINT32_MAX)
+ *
-    {
+ * @param v  vector to pop from
-        const uint32_t index = pool->free;
+ */
+static void vec_pop(vector_t *v) {
+    if (v->count > 0) v->count--;
+}
 
-        pool->free = (uint32_t) pool->data[index * pool->stripe];
+/**
-
+ * Remove the element at index by swapping in the last element (O(1)).
-        return index;
+ * Order is not preserved.
+ *
+ * @param v      vector to remove from
+ * @param index  index of the element to remove
+ */
+static void vec_remove(vector_t *v, int index) {
+    if (index < 0 || index >= v->count) return;
+    if (index < v->count - 1) {
+        memcpy(v->data + index * v->stride,
+               v->data + (v->count - 1) * v->stride,
+               v->stride);
     }
-    else
+    v->count--;
-    {
-        if(pool->size >= pool->capacity)
-        {
-            pool->capacity *= 2;
-
-            pool->data = (void**) realloc(pool->data, pool->capacity * pool->stripe);
-        }
-
-        return pool->size++;
-    }
-}
-static const void* pool_get(mem_pool_t *pool, uint32_t index)
-{
-    assert(index > 0);
-    assert(index < pool->capacity);
-
-    return pool->data[index * pool->stripe];
-}
-static void pool_remove(mem_pool_t *pool, uint32_t index)
-{
-    const uint32_t pos = index * pool->stripe;
-
-    pool->data[pos] = (void*) pool->free;
-    pool->free = index;
 }
 
-#endif
+/**
+ * Return a pointer to the element at index (no bounds check).
+ *
+ * @param v      vector to access
+ * @param index  element index
+ * @return       pointer to the element
+ */
+static void *vec_get(vector_t *v, int index) {
+    return v->data + index * v->stride;
+}
+
+/**
+ * Free the backing array and reset the vector to empty.
+ *
+ * @param v  vector to free
+ */
+static void vec_free(vector_t *v) {
+    if (v->data) FREE(v->data);
+    v->data = NULL;
+    v->count = 0;
+    v->capacity = 0;
+}
+
+#endif