RLGL Hello triangle example.

1 files changed, 177 insertions, 0 deletions

diff --git a/examples/rlgl_hello_triangle/main.lua b/examples/rlgl_hello_triangle/main.lua
new file mode 100644
index 0000000..571acb0
--- /dev/null
+++ b/examples/rlgl_hello_triangle/main.lua
@@ -0,0 +1,177 @@
+package.path = package.path..";"..RL.GetBasePath().."../resources/lib/?.lua"
+
+Util = require( "utillib" )
+Vec2 = require( "vector2" )
+
+local res = Vec2:new( 1024, 720 )
+local winScale = 1
+local winSize = res:scale( winScale )
+local monitor = 0
+
+local triangle = {
+	texture = {
+		id = -1,
+		data = nil,
+		size = Vec2:new(),
+		mipmaps = 0,
+		format = 0,
+	},
+	vao = -1,
+	vbos = {
+		positions = -1,
+		texcoords = -1,
+		colors = -1,
+	},
+}
+
+local vertexShader = [[
+	#version 330 core
+	layout (location = 0) in vec3 aPos;
+	layout (location = 1) in vec4 aColor;
+	layout (location = 2) in vec2 aTexCoord;
+	
+	out vec4 flagColor;
+	out vec2 fragTexCoord;
+	
+	void main() {
+		flagColor = aColor;
+		fragTexCoord = aTexCoord;
+		gl_Position = vec4( aPos, 1.0 );
+	}
+]]
+local fragmentShader = [[
+	#version 330 core
+	out vec4 FragColor;
+	
+	in vec4 flagColor;
+	in vec2 fragTexCoord;
+
+	uniform sampler2D ourTexture;
+
+	void main() {
+		FragColor = texture( ourTexture, fragTexCoord ) * flagColor;
+	}
+]]
+
+local shaderProgram = -1
+
+-- Let's make our own custom texture.
+local function loadTexture( path )
+	local image = RL.LoadImage( path )
+
+	triangle.texture.data = RL.GetImageData( image )
+	triangle.texture.size = Vec2:new( RL.GetImageSize( image ) )
+	triangle.texture.format = RL.GetImageFormat( image )
+	triangle.texture.mipmaps = RL.GetImageMipmaps( image )
+
+	triangle.texture.id = RL.rlLoadTexture(
+		triangle.texture.data,
+		triangle.texture.size,
+		triangle.texture.format,
+		triangle.texture.mipmaps
+	)
+end
+
+local function createTriangle()
+	loadTexture( RL.GetBasePath().."../resources/images/monkey_tex.png" )
+	-- Set texture to shader uniform.
+	local shaderLoc = RL.rlGetLocationUniform( shaderProgram, "ourTexture" )
+
+	RL.rlEnableShader( shaderProgram )
+	-- NOTE: Default texture is always activated as GL_TEXTURE0 so our slot will be 1.
+	RL.rlSetUniformSampler( shaderLoc, triangle.texture.id )
+	RL.rlDisableShader()
+
+	-- Setup triangle buffers.
+	triangle.vao = RL.rlLoadVertexArray()
+	RL.rlEnableVertexArray( triangle.vao )
+
+	-- Positions.
+	local vertexBuffer = RL.LoadBuffer(
+		{
+			-0.5, -0.5, 0.0,
+			0.5, -0.5, 0.0,
+			0.0,  0.5, 0.0
+		},
+		RL.BUFFER_FLOAT
+	)
+	triangle.vbos.positions = RL.rlLoadVertexBuffer( vertexBuffer, false )
+	RL.rlSetVertexAttribute( 0, 3, RL.RL_FLOAT, false, 0, 0 )
+	RL.rlEnableVertexAttribute( 0 )
+
+	-- Colors.
+	local colors = RL.LoadBuffer(
+		{
+			1, 0, 0, 1,
+			0, 1, 0, 1,
+			0, 0, 1, 1
+		},
+		RL.BUFFER_FLOAT
+	)
+	triangle.vbos.colors = RL.rlLoadVertexBuffer( colors, false )
+	RL.rlSetVertexAttribute( 1, 4, RL.RL_FLOAT, false, 0, 0 )
+	RL.rlEnableVertexAttribute( 1 )
+
+	-- Texcoords.
+	local texcoors = RL.LoadBuffer(
+		{
+			0, 0,
+			1, 0,
+			0.5, 1,
+		},
+		RL.BUFFER_FLOAT
+	)
+	triangle.vbos.texcoors = RL.rlLoadVertexBuffer( texcoors, false )
+	RL.rlSetVertexAttribute( 2, 2, RL.RL_FLOAT, false, 0, 0 )
+	RL.rlEnableVertexAttribute( 2 )
+
+	-- Disable.
+	RL.rlDisableVertexBuffer()
+	RL.rlDisableVertexArray()
+end
+
+function RL.init()
+	local monitorPos = Vec2:new( RL.GetMonitorPosition( monitor ) )
+	local monitorSize = Vec2:new( RL.GetMonitorSize( monitor ) )
+
+	RL.SetWindowTitle( "RLGL Hello Triangle" )
+	RL.SetWindowState( RL.FLAG_WINDOW_RESIZABLE )
+	RL.SetWindowState( RL.FLAG_VSYNC_HINT )
+	RL.SetWindowSize( winSize )
+	RL.SetWindowPosition( { monitorPos.x + monitorSize.x / 2 - winSize.x / 2, monitorPos.y + monitorSize.y / 2 - winSize.y / 2 } )
+
+	RL.rlViewport( { 0, 0, res.x ,res.y } )
+	shaderProgram = RL.rlLoadShaderCode( vertexShader, fragmentShader )
+
+	createTriangle()
+end
+
+local function drawTriangle()
+	-- Texture slot 0 is the default texture.
+	RL.rlActiveTextureSlot( 1 )
+	RL.rlEnableTexture( triangle.texture.id )
+
+	RL.rlEnableShader( shaderProgram )
+
+	RL.rlEnableVertexArray( triangle.vao )
+	RL.rlDrawVertexArray( 0, 3 )
+
+	-- Disable.
+	RL.rlDisableVertexArray()
+	RL.rlDisableVertexBuffer()
+	RL.rlDisableTexture()
+	RL.rlDisableShader()
+end
+
+function RL.draw()
+	RL.ClearBackground( RL.BLACK )
+	drawTriangle()
+end
+
+function RL.exit()
+	RL.rlUnloadVertexArray( triangle.vao )
+	RL.rlUnloadVertexBuffer( triangle.vbos.positions )
+	RL.rlUnloadVertexBuffer( triangle.vbos.colors )
+	RL.rlUnloadVertexBuffer( triangle.vbos.texcoords )
+	RL.rlUnloadTexture( triangle.texture.id )
+end