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JavaGraphicsAlgorithms

alt text

This project started as an intermediate level of developing my other project ConcreteView which uses OpenGL-ES but i had no experience and knowledge about Computer Graphics so i started from the book "Computer Graphics for Java Programmers" by Leen Ammeraal. The book explains gradually every basic aspect of computer graphics such as coordinate systems and transformations from one to another, orthographic and perspective projection, data modelling, triangulation of polygons etc. It presents three algorithms for representing 3D objects which are :

 -Painter Algorithm
-zBuffer Algorithm
-Hidden Line Algorithm

Note: zBuffer in most cases shows the same result as Painter, but in some cases zBuffer is better. Painter Algorithm sorts all triangles by the average depth value of three vertices and start painting triangels from farther to nearer, so it paints nearer triangles over the farther. There is a problem with painter algorithm when you have intersecting triangles with similar depth values. For these occasions zBuffer takes care of this problem by having an array in which it holds for every pixel the minimum depth of the elements that were drew in it and every time it tries to draw something in this pixel checks if it is nearer, if yes it paints it and if no it proceeds to the next element.

I added some features such as controling the view with mouse instead of clicking the menu and painting the back buffer before showing it instead of repainting every time you change point of view. My final goal was to create a 3D model of steel that is contained in reinforced concrete beams. To achieve that i took the torus that you see in the picture above, rotate it and moved each quarter by some distance to achieve the result you see in the picture below.

alt text

Below are some photos of steel and torus objects as shown by Hidden Line Algorithm:

alt text

alt text

, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
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}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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JavaGraphicsAlgorithms
alt text
This project started as an intermediate level of developing my other project ConcreteView which uses OpenGL-ES but i had no experience and knowledge about Computer Graphics so i started from the book "Computer Graphics for Java Programmers" by Leen Ammeraal. The book explains gradually every basic aspect of computer graphics such as coordinate systems and transformations from one to another, orthographic and perspective projection, data modelling, triangulation of polygons etc. It presents three algorithms for representing 3D objects which are :
 -Painter Algorithm
-zBuffer Algorithm
-Hidden Line Algorithm

Note: zBuffer in most cases shows the same result as Painter, but in some cases zBuffer is better. Painter Algorithm sorts all triangles by the average depth value of three vertices and start painting triangels from farther to nearer, so it paints nearer triangles over the farther. There is a problem with painter algorithm when you have intersecting triangles with similar depth values. For these occasions zBuffer takes care of this problem by having an array in which it holds for every pixel the minimum depth of the elements that were drew in it and every time it tries to draw something in this pixel checks if it is nearer, if yes it paints it and if no it proceeds to the next element.
I added some features such as controling the view with mouse instead of clicking the menu and painting the back buffer before showing it instead of repainting every time you change point of view. My final goal was to create a 3D model of steel that is contained in reinforced concrete beams. To achieve that i took the torus that you see in the picture above, rotate it and moved each quarter by some distance to achieve the result you see in the picture below.
alt text
Below are some photos of steel and torus objects as shown by Hidden Line Algorithm:
alt text
alt text

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
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} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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JavaGraphicsAlgorithms
alt text
This project started as an intermediate level of developing my other project ConcreteView which uses OpenGL-ES but i had no experience and knowledge about Computer Graphics so i started from the book "Computer Graphics for Java Programmers" by Leen Ammeraal. The book explains gradually every basic aspect of computer graphics such as coordinate systems and transformations from one to another, orthographic and perspective projection, data modelling, triangulation of polygons etc. It presents three algorithms for representing 3D objects which are :
 -Painter Algorithm
-zBuffer Algorithm
-Hidden Line Algorithm

Note: zBuffer in most cases shows the same result as Painter, but in some cases zBuffer is better. Painter Algorithm sorts all triangles by the average depth value of three vertices and start painting triangels from farther to nearer, so it paints nearer triangles over the farther. There is a problem with painter algorithm when you have intersecting triangles with similar depth values. For these occasions zBuffer takes care of this problem by having an array in which it holds for every pixel the minimum depth of the elements that were drew in it and every time it tries to draw something in this pixel checks if it is nearer, if yes it paints it and if no it proceeds to the next element.
I added some features such as controling the view with mouse instead of clicking the menu and painting the back buffer before showing it instead of repainting every time you change point of view. My final goal was to create a 3D model of steel that is contained in reinforced concrete beams. To achieve that i took the torus that you see in the picture above, rotate it and moved each quarter by some distance to achieve the result you see in the picture below.
alt text
Below are some photos of steel and torus objects as shown by Hidden Line Algorithm:
alt text
alt text

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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JavaGraphicsAlgorithms
alt text
This project started as an intermediate level of developing my other project ConcreteView which uses OpenGL-ES but i had no experience and knowledge about Computer Graphics so i started from the book "Computer Graphics for Java Programmers" by Leen Ammeraal. The book explains gradually every basic aspect of computer graphics such as coordinate systems and transformations from one to another, orthographic and perspective projection, data modelling, triangulation of polygons etc. It presents three algorithms for representing 3D objects which are :
 -Painter Algorithm
-zBuffer Algorithm
-Hidden Line Algorithm

Note: zBuffer in most cases shows the same result as Painter, but in some cases zBuffer is better. Painter Algorithm sorts all triangles by the average depth value of three vertices and start painting triangels from farther to nearer, so it paints nearer triangles over the farther. There is a problem with painter algorithm when you have intersecting triangles with similar depth values. For these occasions zBuffer takes care of this problem by having an array in which it holds for every pixel the minimum depth of the elements that were drew in it and every time it tries to draw something in this pixel checks if it is nearer, if yes it paints it and if no it proceeds to the next element.
I added some features such as controling the view with mouse instead of clicking the menu and painting the back buffer before showing it instead of repainting every time you change point of view. My final goal was to create a 3D model of steel that is contained in reinforced concrete beams. To achieve that i took the torus that you see in the picture above, rotate it and moved each quarter by some distance to achieve the result you see in the picture below.
alt text
Below are some photos of steel and torus objects as shown by Hidden Line Algorithm:
alt text
alt text

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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JavaGraphicsAlgorithms
alt text
This project started as an intermediate level of developing my other project ConcreteView which uses OpenGL-ES but i had no experience and knowledge about Computer Graphics so i started from the book "Computer Graphics for Java Programmers" by Leen Ammeraal. The book explains gradually every basic aspect of computer graphics such as coordinate systems and transformations from one to another, orthographic and perspective projection, data modelling, triangulation of polygons etc. It presents three algorithms for representing 3D objects which are :
 -Painter Algorithm
-zBuffer Algorithm
-Hidden Line Algorithm

Note: zBuffer in most cases shows the same result as Painter, but in some cases zBuffer is better. Painter Algorithm sorts all triangles by the average depth value of three vertices and start painting triangels from farther to nearer, so it paints nearer triangles over the farther. There is a problem with painter algorithm when you have intersecting triangles with similar depth values. For these occasions zBuffer takes care of this problem by having an array in which it holds for every pixel the minimum depth of the elements that were drew in it and every time it tries to draw something in this pixel checks if it is nearer, if yes it paints it and if no it proceeds to the next element.
I added some features such as controling the view with mouse instead of clicking the menu and painting the back buffer before showing it instead of repainting every time you change point of view. My final goal was to create a 3D model of steel that is contained in reinforced concrete beams. To achieve that i took the torus that you see in the picture above, rotate it and moved each quarter by some distance to achieve the result you see in the picture below.
alt text
Below are some photos of steel and torus objects as shown by Hidden Line Algorithm:
alt text
alt text

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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JavaGraphicsAlgorithms
alt text
This project started as an intermediate level of developing my other project ConcreteView which uses OpenGL-ES but i had no experience and knowledge about Computer Graphics so i started from the book "Computer Graphics for Java Programmers" by Leen Ammeraal. The book explains gradually every basic aspect of computer graphics such as coordinate systems and transformations from one to another, orthographic and perspective projection, data modelling, triangulation of polygons etc. It presents three algorithms for representing 3D objects which are :
 -Painter Algorithm
-zBuffer Algorithm
-Hidden Line Algorithm

Note: zBuffer in most cases shows the same result as Painter, but in some cases zBuffer is better. Painter Algorithm sorts all triangles by the average depth value of three vertices and start painting triangels from farther to nearer, so it paints nearer triangles over the farther. There is a problem with painter algorithm when you have intersecting triangles with similar depth values. For these occasions zBuffer takes care of this problem by having an array in which it holds for every pixel the minimum depth of the elements that were drew in it and every time it tries to draw something in this pixel checks if it is nearer, if yes it paints it and if no it proceeds to the next element.
I added some features such as controling the view with mouse instead of clicking the menu and painting the back buffer before showing it instead of repainting every time you change point of view. My final goal was to create a 3D model of steel that is contained in reinforced concrete beams. To achieve that i took the torus that you see in the picture above, rotate it and moved each quarter by some distance to achieve the result you see in the picture below.
alt text
Below are some photos of steel and torus objects as shown by Hidden Line Algorithm:
alt text
alt text

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
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} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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JavaGraphicsAlgorithms
alt text
This project started as an intermediate level of developing my other project ConcreteView which uses OpenGL-ES but i had no experience and knowledge about Computer Graphics so i started from the book "Computer Graphics for Java Programmers" by Leen Ammeraal. The book explains gradually every basic aspect of computer graphics such as coordinate systems and transformations from one to another, orthographic and perspective projection, data modelling, triangulation of polygons etc. It presents three algorithms for representing 3D objects which are :
 -Painter Algorithm
-zBuffer Algorithm
-Hidden Line Algorithm

Note: zBuffer in most cases shows the same result as Painter, but in some cases zBuffer is better. Painter Algorithm sorts all triangles by the average depth value of three vertices and start painting triangels from farther to nearer, so it paints nearer triangles over the farther. There is a problem with painter algorithm when you have intersecting triangles with similar depth values. For these occasions zBuffer takes care of this problem by having an array in which it holds for every pixel the minimum depth of the elements that were drew in it and every time it tries to draw something in this pixel checks if it is nearer, if yes it paints it and if no it proceeds to the next element.
I added some features such as controling the view with mouse instead of clicking the menu and painting the back buffer before showing it instead of repainting every time you change point of view. My final goal was to create a 3D model of steel that is contained in reinforced concrete beams. To achieve that i took the torus that you see in the picture above, rotate it and moved each quarter by some distance to achieve the result you see in the picture below.
alt text
Below are some photos of steel and torus objects as shown by Hidden Line Algorithm:
alt text
alt text

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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JavaGraphicsAlgorithms
alt text
This project started as an intermediate level of developing my other project ConcreteView which uses OpenGL-ES but i had no experience and knowledge about Computer Graphics so i started from the book "Computer Graphics for Java Programmers" by Leen Ammeraal. The book explains gradually every basic aspect of computer graphics such as coordinate systems and transformations from one to another, orthographic and perspective projection, data modelling, triangulation of polygons etc. It presents three algorithms for representing 3D objects which are :
 -Painter Algorithm
-zBuffer Algorithm
-Hidden Line Algorithm

Note: zBuffer in most cases shows the same result as Painter, but in some cases zBuffer is better. Painter Algorithm sorts all triangles by the average depth value of three vertices and start painting triangels from farther to nearer, so it paints nearer triangles over the farther. There is a problem with painter algorithm when you have intersecting triangles with similar depth values. For these occasions zBuffer takes care of this problem by having an array in which it holds for every pixel the minimum depth of the elements that were drew in it and every time it tries to draw something in this pixel checks if it is nearer, if yes it paints it and if no it proceeds to the next element.
I added some features such as controling the view with mouse instead of clicking the menu and painting the back buffer before showing it instead of repainting every time you change point of view. My final goal was to create a 3D model of steel that is contained in reinforced concrete beams. To achieve that i took the torus that you see in the picture above, rotate it and moved each quarter by some distance to achieve the result you see in the picture below.
alt text
Below are some photos of steel and torus objects as shown by Hidden Line Algorithm:
alt text
alt text