1 files changed, 120 insertions, 0 deletions

diff --git a/gfx-iso/app/checkerboard.c b/gfx-iso/app/checkerboard.c
new file mode 100644
index 0000000..8b394c4
--- /dev/null
+++ b/gfx-iso/app/checkerboard.c
@@ -0,0 +1,120 @@
+#include "isogfx-demo.h"
+
+#include <gfx/gfx_app.h>
+#include <isogfx/isogfx.h>
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+static const int TILE_WIDTH   = 64;
+static const int TILE_HEIGHT  = TILE_WIDTH / 2;
+static const int WORLD_WIDTH  = 20;
+static const int WORLD_HEIGHT = 20;
+
+static const TileDesc tile_set[] = {
+    {.type   = TileFromColour,
+     .width  = TILE_WIDTH,
+     .height = TILE_HEIGHT,
+     .colour = (Pixel){.r = 0x38, .g = 0x3b, .b = 0x46, .a = 0xff}},
+    {.type   = TileFromColour,
+     .width  = TILE_WIDTH,
+     .height = TILE_HEIGHT,
+     .colour = (Pixel){.r = 0xA5, .g = 0xb3, .b = 0xc0, .a = 0xff}},
+    {.type   = TileFromColour,
+     .width  = TILE_WIDTH,
+     .height = TILE_HEIGHT,
+     .colour = (Pixel){.r = 0xdc, .g = 0x76, .b = 0x84, .a = 0xff}},
+};
+
+typedef enum Colour {
+  Black,
+  White,
+  Red,
+} Colour;
+
+typedef struct State {
+  Tile red;
+  int  xpick;
+  int  ypick;
+} State;
+
+static void make_checkerboard(IsoGfx* iso, Tile black, Tile white) {
+  assert(iso);
+  for (int y = 0; y < isogfx_world_height(iso); ++y) {
+    for (int x = 0; x < isogfx_world_width(iso); ++x) {
+      const int  odd_col = x & 1;
+      const int  odd_row = y & 1;
+      const Tile value   = (odd_row ^ odd_col) == 0 ? black : white;
+      isogfx_set_tile(iso, x, y, value);
+    }
+  }
+}
+
+static void shutdown(IsoGfx* iso, void* app_state) {
+  assert(iso);
+  if (app_state) {
+    free(app_state);
+  }
+}
+
+static void update(IsoGfx* iso, void* app_state, double t, double dt) {
+  assert(iso);
+  assert(app_state);
+  State* state = (State*)(app_state);
+
+  double mouse_x, mouse_y;
+  gfx_app_get_mouse_position(&mouse_x, &mouse_y);
+
+  isogfx_pick_tile(iso, mouse_x, mouse_y, &state->xpick, &state->ypick);
+
+  printf("Picked tile: (%d, %d)\n", state->xpick, state->ypick);
+}
+
+static void render(IsoGfx* iso, void* app_state) {
+  assert(iso);
+  assert(app_state);
+  State* state = (State*)(app_state);
+
+  isogfx_render(iso);
+  if ((state->xpick != -1) && (state->ypick != -1)) {
+    isogfx_draw_tile(iso, state->xpick, state->ypick, state->red);
+  }
+}
+
+bool make_checkerboard_app(IsoGfx* iso, IsoGfxApp* app) {
+  assert(iso);
+  assert(app);
+
+  State* state = calloc(1, sizeof(State));
+  if (!state) {
+    return false;
+  }
+
+  if (!isogfx_make_world(
+          iso, &(WorldDesc){
+                   .tile_width   = TILE_WIDTH,
+                   .tile_height  = TILE_HEIGHT,
+                   .world_width  = WORLD_WIDTH,
+                   .world_height = WORLD_HEIGHT})) {
+    goto cleanup;
+  }
+
+  const Tile black = isogfx_make_tile(iso, &tile_set[Black]);
+  const Tile white = isogfx_make_tile(iso, &tile_set[White]);
+  state->red       = isogfx_make_tile(iso, &tile_set[Red]);
+  make_checkerboard(iso, black, white);
+  isogfx_render(iso);
+
+  app->state    = state;
+  app->shutdown = shutdown;
+  app->update   = update;
+  app->render   = render;
+
+  return true;
+
+cleanup:
+  free(state);
+  return false;
+}