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texture1.html
<!doctype html>
<head>
<title>texture1</title>
<script src="minMatrix.js"></script>
</head>
 
<body>
<canvas id="canvas" width="640" height="480"></canvas>
<div id="msg"></div>
<script id="vs" type="text/x-vertex">
 
// 頂点シェイダー
attribute vec3 position;
attribute vec2 textureCoord;
uniform mat4 mvpMatrix;
varying vec2 vTextureCoord;
 
void main(void) {
	vTextureCoord = textureCoord;
	gl_Position = mvpMatrix * vec4(position, 1.0);
}
 
</script>
<script id="fs" type="text/x-fragment">
 
// 断片シェイダー
precision mediump float;
 
uniform sampler2D texture;
varying vec2 vTextureCoord;
 
void main(void) {
	vec4 smpColor = texture2D(texture, vTextureCoord);
	gl_FragColor = vec4(1,1,1,1) * smpColor;
}
 
</script>
<script>
 
var gl;	// webgl context
var uniLocation = [];	// uniform
var m = new matIV();
var mMatrix = m.identity(m.create());	// model
var pMatrix = m.identity(m.create());	// perspective
var index;
var texture = null;
 
var lat = 0;	// 緯度
var lon = 90;	// 経度
var dist = 3;	// 距離
 
onload = function() {
	gl = canvas.getContext("experimental-webgl");
 
	var vShader = createShader("vs");
	var fShader = createShader("fs");
	var program = createProgram(vShader, fShader);
 
	gl.activeTexture(gl.TEXTURE0);
	createTexture("texture.png");
 
	var position = [	// x, y, z
		0, 0, 0,
		0, 1, 0,
		1, 1, 0,
		1, 0, 0,
	];
	var textureCoord = [	// u, v
		0, 1,
		0, 0,
		1, 0,
		1, 1,
	];
	index = [
		0, 1, 2,
		2, 3, 0,
	];
 
	setAttribute(program, "position", position, 3);
	setAttribute(program, "textureCoord", textureCoord, 2);
	uniLocation[0] = gl.getUniformLocation(program, "mvpMatrix");
	uniLocation[1] = gl.getUniformLocation(program, "texture");
 
	var ibo = gl.createBuffer();
	gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, ibo);
	gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, new Int16Array(index), gl.STATIC_DRAW);
 
	m.perspective(45, canvas.width / canvas.height, 0.1, 10, pMatrix);
 
	draw();
 
	// イベント
	var px, py;
	var drag = false;
	canvas.onmousedown = function(e) {
		drag = true;
	};
	canvas.onmouseup = function(e) {
		drag = false;
	};
	canvas.onmousemove = function(e) {
		if (drag) {
			lat = Math.min(Math.max(lat + (e.clientY - py), -90), 90);
			lon += (e.clientX - px);
			while (lon < 0) lon += 360;
			lon %= 360;
			draw();
		}
		px = e.clientX;
		py = e.clientY;
	};
	canvas.onmousewheel = function(e) {
		dist = Math.max(dist - 0.1 * e.wheelDelta / 120, 0);
		draw();
	};
};
 
function draw() {
	msg.innerHTML = "lat:" + lat + " lon:" + lon + " dist:" + dist.toFixed(1);
 
	var rad = lat * Math.PI / 180;
	var y = Math.sin(rad) * dist;
	var r = Math.cos(rad) * dist;
	var rad = lon * Math.PI / 180;
	var x = Math.cos(rad) * r;
	var z = Math.sin(rad) * r;
 
	var vMatrix = m.identity(m.create());
	var mvpMatrix = m.identity(m.create());
	m.lookAt([x, y, z], [0, 0, 0], [0, 1, 0], vMatrix);
	m.multiply(pMatrix, vMatrix, mvpMatrix);
	m.multiply(mvpMatrix, mMatrix, mvpMatrix);
 
	gl.clearColor(0x64 / 0xff, 0x95 / 0xff, 0xed / 0xff, 1);
	gl.clearDepth(1);
	gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
 
	gl.bindTexture(gl.TEXTURE_2D, texture);
	gl.uniformMatrix4fv(uniLocation[0], false, mvpMatrix);
	gl.uniform1i(uniLocation[1], 0);
	gl.drawElements(gl.TRIANGLES, index.length, gl.UNSIGNED_SHORT, 0);
	gl.flush();
}
 
function createShader(id) {
	var element = document.getElementById(id);
	if (! element) return;
 
	const types = {
		"text/x-vertex": gl.VERTEX_SHADER,
		"text/x-fragment": gl.FRAGMENT_SHADER,
	};
	var shader = gl.createShader(types[element.type]);
	gl.shaderSource(shader, element.text);
	gl.compileShader(shader);
 
	if (! gl.getShaderParameter(shader, gl.COMPILE_STATUS)) {
		alert(gl.getShaderInfoLog(shader));
		return;
	}
	return shader;
}
 
function createProgram(vs, fs) {
	var program = gl.createProgram();
	gl.attachShader(program, vs);
	gl.attachShader(program, fs);
	gl.linkProgram(program);
 
	if (! gl.getProgramParameter(program, gl.LINK_STATUS)) {
		alert(gl.getProgramInfoLog(program));
		return;
	}
	gl.useProgram(program);
	return program;
}
 
function createTexture(src) {
	var img = new Image();
	img.onload = function() {
		var tex = gl.createTexture();
		gl.bindTexture(gl.TEXTURE_2D, tex);
		gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.RGBA, gl.UNSIGNED_BYTE, img);
		gl.generateMipmap(gl.TEXTURE_2D);
		gl.bindTexture(gl.TEXTURE_2D, null);
		texture = tex;
	};
	img.src = src;
}
 
function setAttribute(program, name, data, stride) {
	var vbo = gl.createBuffer();
	gl.bindBuffer(gl.ARRAY_BUFFER, vbo);
	gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(data), gl.STATIC_DRAW);
 
	var location = gl.getAttribLocation(program, name);
	gl.enableVertexAttribArray(location);
	gl.vertexAttribPointer(location, stride, gl.FLOAT, false, 0, 0);
	gl.bindBuffer(gl.ARRAY_BUFFER, null);
}
 
</script>
</body>
 
最終更新:2016年02月15日 09:52