--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/hello_triangle.nim	Mon Feb 24 10:09:41 2025 +0700
@@ -0,0 +1,89 @@
+import ../semicongine
+import ../semicongine/rendering
+import ../semicongine/input
+
+# required
+initEngine("Hello triangle")
+
+# set up a simple render pass to render the displayed frame
+var renderpass = createDirectPresentationRenderPass(
+  depthBuffer = false, samples = VK_SAMPLE_COUNT_1_BIT
+)
+
+# the swapchain, needs to be attached to the main renderpass
+setupSwapchain(renderpass = renderpass)
+
+# render data is used for memory management on the GPU
+var renderdata = initRenderData()
+
+type
+  # define a push constant, to have something moving
+  PushConstant = object
+    scale: float32
+
+  # This is how we define shaders: the interface needs to be "typed"
+  # but the shader code itself can freely be written in glsl
+  Shader = object
+    position {.VertexAttribute.}: Vec3f
+    color {.VertexAttribute.}: Vec3f
+    pushConstant {.PushConstant.}: PushConstant
+    fragmentColor {.Pass.}: Vec3f
+    outColor {.ShaderOutput.}: Vec4f
+    # code
+    vertexCode: string =
+      """void main() {
+    fragmentColor = color;
+    gl_Position = vec4(position * pushConstant.scale, 1);}"""
+    fragmentCode: string =
+      """void main() {
+    outColor = vec4(fragmentColor, 1);}"""
+
+  # And we also need to define our Mesh, which does describe the vertex layout
+  TriangleMesh = object
+    position: GPUArray[Vec3f, VertexBuffer]
+    color: GPUArray[Vec3f, VertexBuffer]
+
+# instantiate the mesh and fill with data
+var mesh = TriangleMesh(
+  position: asGPUArray([vec3(-0.5, -0.5), vec3(0, 0.5), vec3(0.5, -0.5)], VertexBuffer),
+  color: asGPUArray([vec3(0, 0, 1), vec3(0, 1, 0), vec3(1, 0, 0)], VertexBuffer),
+)
+
+# this allocates GPU data, uploads the data to the GPU and flushes any thing that is host-cached
+# this is a shortcut version, more fine-grained control is possible
+assignBuffers(renderdata, mesh)
+renderdata.flushAllMemory()
+
+# Now we need to instantiate the shader as a pipeline object that is attached to a renderpass
+var pipeline = createPipeline(Shader(), renderPass = renderPass)
+
+# the main render-loop will exit if we get a kill-signal from the OS
+while updateInputs():
+  # starts the drawing for the next frame and provides us necesseary framebuffer and commandbuffer objects in this scope
+  withNextFrame(framebuffer, commandbuffer):
+    # start the main (and only) renderpass we have, needs to know the target framebuffer and a commandbuffer
+    withRenderPass(
+      renderPass,
+      framebuffer,
+      commandbuffer,
+      frameWidth(),
+      frameHeight(),
+      vec4(0, 0, 0, 0),
+    ):
+      # now activate our shader-pipeline
+      withPipeline(commandbuffer, pipeline):
+        # and finally, draw the mesh and set a single parameter
+        # more complicated setups with descriptors/uniforms are of course possible
+        renderWithPushConstant(
+          commandbuffer = commandbuffer,
+          pipeline = pipeline,
+          mesh = mesh,
+          pushConstant = PushConstant(scale: 0.3),
+        )
+
+# cleanup
+checkVkResult vkDeviceWaitIdle(engine().vulkan.device)
+destroyPipeline(pipeline)
+destroyRenderData(renderdata)
+destroyRenderPass(renderpass)
+destroyVulkan()