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Copyright (c) 2019 The Khronos Group Inc.
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Test if mipmap incomplete textures can be used as FBO attachments, and mipmap generation on a texture filled by an FBO works correctly</title>
<link rel="stylesheet" href="../../../resources/js-test-style.css"/>
<script src="../../../js/js-test-pre.js"></script>
<script src="../../../js/webgl-test-utils.js"></script>
</head>
<body>
<canvas id="example" width="24" height="24"></canvas>
<div id="description"></div>
<div id="console"></div>
<script>
"use strict";

var wtu = WebGLTestUtils;
description();

var gl = wtu.create3DContext("example");

function testMipmapGeneration() {
    // setup render target texture //
    var texture = gl.createTexture();
    gl.bindTexture(gl.TEXTURE_2D, texture);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
    gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR_MIPMAP_LINEAR);
    gl.texImage2D(gl.TEXTURE_2D, 0, gl.RGBA, 32, 32, 0, gl.RGBA, gl.UNSIGNED_BYTE, null);
    gl.bindTexture(gl.TEXTURE_2D, null);

    // setup framebuffer //
    var fbo = gl.createFramebuffer();
    gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
    gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0);
    gl.bindFramebuffer(gl.FRAMEBUFFER, null);

    // fill the framebuffer //
    gl.bindFramebuffer(gl.FRAMEBUFFER, fbo);
    gl.viewport(0, 0, 32, 32);
    gl.clearColor(1, 0, 1, 1);
    gl.clear(gl.COLOR_BUFFER_BIT);
    gl.bindFramebuffer(gl.FRAMEBUFFER, null);

    // generate mipmap //
    gl.bindTexture(gl.TEXTURE_2D, texture);
    gl.generateMipmap(gl.TEXTURE_2D);

    var program = wtu.setupTexturedQuad(gl);
    gl.viewport(0, 0, gl.canvas.width, gl.canvas.height);
    gl.drawArrays(gl.TRIANGLES, 0, 6);

    // readback //
    wtu.checkCanvas(gl, [255, 0, 255, 255]);
}

var testCubemapFaceWithIncompleteMipmapInFBO = function() {
    // Create a cube map texture that's not mipmap complete.
    var tex2 = gl.createTexture();
    gl.bindTexture(gl.TEXTURE_CUBE_MAP, tex2);
    gl.texParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
    gl.texParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_MIN_FILTER, gl.LINEAR_MIPMAP_LINEAR);

    var cube_map_faces = [
        gl.TEXTURE_CUBE_MAP_POSITIVE_X,
        gl.TEXTURE_CUBE_MAP_NEGATIVE_X,
        gl.TEXTURE_CUBE_MAP_POSITIVE_Y,
        gl.TEXTURE_CUBE_MAP_NEGATIVE_Y,
        gl.TEXTURE_CUBE_MAP_POSITIVE_Z,
        gl.TEXTURE_CUBE_MAP_NEGATIVE_Z
    ];
    for (var i = 0; i < cube_map_faces.length; ++i) {
        gl.texImage2D(cube_map_faces[i], 0, gl.RGBA, 32, 32, 0, gl.RGBA, gl.UNSIGNED_BYTE, null);
    }

    var fb2 = gl.createFramebuffer();
    gl.bindFramebuffer(gl.FRAMEBUFFER, fb2);
    gl.framebufferTexture2D(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_CUBE_MAP_POSITIVE_X, tex2, 0);
    wtu.glErrorShouldBe(gl, gl.NO_ERROR, "Should be no errors after attaching cube map face.");
    shouldBe("gl.checkFramebufferStatus(gl.FRAMEBUFFER)", "gl.FRAMEBUFFER_COMPLETE");
    gl.bindTexture(gl.TEXTURE_CUBE_MAP, null);

    var colorProgram = wtu.setupColorQuad(gl);
    var colorLocation = gl.getUniformLocation(colorProgram, 'u_color');
    gl.uniform4f(colorLocation, 0.0, 1.0, 0.0, 1.0);
    gl.viewport(0, 0, 32, 32);
    wtu.drawUnitQuad(gl);
    // Read what's in the framebuffer - note that we need to use checkCanvasRect since the
    // FB dimensions are different from canvas dimensions.
    wtu.checkCanvasRect(gl, 0, 0, 32, 32, [0, 255, 0, 255],
                        "Framebuffer with a non-mipmap complete cube map attachment should be green");
}

testMipmapGeneration();
debug("");
testCubemapFaceWithIncompleteMipmapInFBO();

var successfullyParsed = true;
</script>
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