Improve meson build.

-Add all required packages as wrap dependencies
-Move source lsitnings to separate files
-Proper dependencies declarations
-Set global D compiler arguments
-Add few asserts
-Add test exe
-Other small improvements

Tested with dmd with betterC, demos executable has to be run from 'demos' directory to properly load assets.

demos/utils/meson.build

@@ -1,31 +1,25 @@
-#project('ECSUtils', 'd')
+# Files
+utils_src = files()
+subdir('source/ecs_utils')
 
-utils_src = [
-    'source/ecs_utils/gfx/mesh.d',
-    'source/ecs_utils/gfx/sprite.d',
-    'source/ecs_utils/gfx/mesh_module.d',
-    'source/ecs_utils/gfx/material.d',
-    'source/ecs_utils/gfx/shader.d',
-    'source/ecs_utils/gfx/vertex.d',
-    'source/ecs_utils/gfx/config.d',
-    'source/ecs_utils/gfx/buffer.d',
-    'source/ecs_utils/gfx/render_list.d',
-    'source/ecs_utils/gfx/renderer.d',
-    'source/ecs_utils/gfx/texture.d',
-    'source/ecs_utils/utils.d',
-    'source/ecs_utils/math/matrix.d',
-    'source/ecs_utils/math/vector.d',
-    'source/ecs_utils/imgui_styles.d',
-    'source/ecs_utils/imgui_bind.d'
-]
+utils_inc = include_directories('source/')
 
-bc_loader_dep = dependency('bindbc-loader', method: 'dub')
-sdl_dep = dependency('bindbc-sdl', method: 'dub')
+# Dependencies
+ecs_utils_lib = library('ecs_utils', utils_src,
+	include_directories : [demos_inc, external_inc, utils_inc],
+	link_args : link_args, 
+	d_module_versions : versions,
+	dependencies : [
+		decs_dep,
+		bindbc_loader_dep,
+		bindbc_sdl_dep,
+	]
+)
 
-utils_inc = include_directories(['source/','../external/sources/'])
-
-ecs_utils_lib = library('ecs_utils', utils_src, include_directories : [utils_inc, inc], d_args: args, link_args: link_args, 
-    d_module_versions: ['BindSDL_Image','SDL_2010'], link_with: ecs_lib, dependencies: [bc_loader_dep,sdl_dep])
+ecs_utils_dep = declare_dependency(
+	include_directories : utils_inc,
+	link_with : ecs_utils_lib,
+)
 #shared_library('ecs_utils', utils_src, include_directories : [utils_inc], d_args: args, link_args: link_args, link_with: ecs_lib)
 
 

demos/utils/source/ecs_utils/meson.build

@@ -0,0 +1,18 @@
+utils_src += files(
+	'gfx/mesh.d',
+	'gfx/sprite.d',
+	'gfx/mesh_module.d',
+	'gfx/material.d',
+	'gfx/shader.d',
+	'gfx/vertex.d',
+	'gfx/config.d',
+	'gfx/buffer.d',
+	'gfx/render_list.d',
+	'gfx/renderer.d',
+	'gfx/texture.d',
+	'utils.d',
+	'math/matrix.d',
+	'math/vector.d',
+	'imgui_styles.d',
+	'imgui_bind.d',
+)