:wMerge branch 'gl-window' into main

2 files changed, 172 insertions, 0 deletions

diff --git a/demo/container.jpg b/demo/container.jpg
new file mode 100644
index 0000000..d07bee4
--- /dev/null
+++ b/demo/container.jpg
diff --git a/demo/honey.lua b/demo/honey.lua
new file mode 100644
index 0000000..822877f
--- /dev/null
+++ b/demo/honey.lua
@@ -0,0 +1,172 @@
+local gl = honey.gl
+local window = honey.window
+
+
+--====== initialize opengl ======--
+
+gl.Init()
+window.setHint(window.hintType.contextVersionMajor, 3)
+window.setHint(window.hintType.contextVersionMinor, 3)
+window.setHint(window.hintType.openGlProfile, window.profileType.openGlCoreProfile)
+
+
+--====== create window ======--
+
+local w = window.create(640, 480, 'hello, world!')
+window.makeContextCurrent(w)
+gl.InitGlad()
+
+window.setFramebufferSizeCallback(w, function(_, width, height)
+	print(string.format("resize: (%d, %d)", width, height))
+	gl.setViewport(0, 0, width, height)
+end)
+
+
+--====== compile shaders ======--
+
+local vertexShaderSource = [[
+#version 330 core
+layout (location = 0) in vec3 aPos;
+layout (location = 1) in vec3 aColor;
+layout (location = 2) in vec2 aTexCoord;
+
+uniform mat4 transform;
+
+out vec3 ourColor;
+out vec2 TexCoord;
+
+void main()
+{
+    gl_Position = transform * vec4(aPos, 1.0);
+    ourColor = aColor;
+    TexCoord = aTexCoord;
+}
+]]
+
+local fragmentShaderSource = [[
+#version 330 core
+out vec4 FragColor;
+  
+in vec3 ourColor;
+in vec2 TexCoord;
+
+uniform sampler2D ourTexture;
+
+void main()
+{
+    FragColor = texture(ourTexture, TexCoord);
+}
+]]
+
+-- vertex shader
+local vertexShader = gl.CreateShader(gl.VERTEX_SHADER)
+gl.ShaderSource(vertexShader, vertexShaderSource)
+gl.CompileShader(vertexShader)
+
+-- fragment shader
+local fragmentShader = gl.CreateShader(gl.FRAGMENT_SHADER)
+gl.ShaderSource(fragmentShader, fragmentShaderSource)
+gl.CompileShader(fragmentShader)
+
+-- link
+local shader = gl.CreateProgram()
+gl.AttachShader(shader, vertexShader)
+gl.AttachShader(shader, fragmentShader)
+gl.LinkProgram(shader)
+-- clean up
+gl.DeleteShader(vertexShader)
+gl.DeleteShader(fragmentShader)
+
+
+--====== set up vertex data ======--
+
+local vertices = {
+--     positions          colors           uvs   
+	 0.5,  0.5, 0.0,   1.0, 0.0, 0.0,   1.0, 1.0, -- top right
+	 0.5, -0.5, 0.0,   0.0, 1.0, 0.0,   1.0, 0.0, -- bottom right
+	-0.5, -0.5, 0.0,   0.0, 0.0, 1.0,   0.0, 0.0, -- bottom let
+	-0.5,  0.5, 0.0,   1.0, 1.0, 0.0,   0.0, 1.0  -- top let 
+}
+local indices = {
+    0, 1, 3, -- first triangle
+    1, 2, 3  -- second triangle
+}
+
+-- buffers
+local vertexArray = gl.GenVertexArrays()
+local vertexBuffer = gl.GenBuffers()
+local elementBuffer = gl.GenBuffers()
+
+gl.BindVertexArray(vertexArray)
+
+gl.BindBuffer(gl.ARRAY_BUFFER, vertexBuffer)
+gl.BufferData(gl.ARRAY_BUFFER, gl.FLOAT, vertices, gl.STATIC_DRAW)
+
+gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, elementBuffer)
+gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, gl.UNSIGNED_INT, indices, gl.STATIC_DRAW)
+
+-- position
+gl.VertexAttribPointer(0, 3, false, 8, 0)
+gl.EnableVertexAttribArray(0)
+
+-- color
+gl.VertexAttribPointer(1, 3, false, 8, 3)
+gl.EnableVertexAttribArray(1)
+
+-- uv
+gl.VertexAttribPointer(2, 2, false, 8, 6)
+gl.EnableVertexAttribArray(2)
+
+
+--====== load texture ======--
+
+local texture = gl.GenTextures()
+gl.BindTexture(gl.TEXTURE_2D, texture)
+
+gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.REPEAT)
+gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.REPEAT)
+
+gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
+gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
+
+local image, width, height = honey.image.load('container.jpg', 3)
+gl.TexImage2D(
+	gl.TEXTURE_2D, 0,
+	gl.RGB, width, height,
+	gl.RGB, gl.UNSIGNED_BYTE,
+	image
+)
+gl.GenerateMipmap(gl.TEXTURE_2D)
+honey.image.destroy(image)
+
+-- connect shader samplers to texture units
+gl.UseProgram(shader)
+gl.Uniform1i(gl.GetUniformLocation(shader, 'ourTexture'), 0)
+
+
+--====== main loop ======--
+
+local transform = honey.glm.mat4()
+
+while not window.shouldClose(w) do
+	gl.ClearColor(0.2, 0.3, 0.3, 1.0)
+	gl.Clear(gl.COLOR_BUFFER_BIT)
+
+	gl.ActiveTexture(0)
+	gl.BindTexture(gl.TEXTURE_2D, texture)
+
+	gl.UseProgram(shader)
+	honey.glm.mat4_identity(transform)
+	local time = window.getTime()
+	honey.glm.rotate_z(transform, time, transform)
+	local transformLocation = gl.GetUniformLocation(shader, 'transform')
+	gl.UniformMatrix4fv(transformLocation, false, transform)
+
+	gl.BindVertexArray(vertexArray)
+	gl.DrawElements(gl.TRIANGLES, 6, gl.UNSIGNED_INT, 0)
+
+	window.swapBuffers(w)
+	window.pollEvents()
+end
+window.destroy(w)
+gl.Terminate()