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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 14:29:10 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 14:29:10 +0000
commit2aa4a82499d4becd2284cdb482213d541b8804dd (patch)
treeb80bf8bf13c3766139fbacc530efd0dd9d54394c /gfx/gl/DecomposeIntoNoRepeatTriangles.cpp
parentInitial commit. (diff)
downloadfirefox-2aa4a82499d4becd2284cdb482213d541b8804dd.tar.xz
firefox-2aa4a82499d4becd2284cdb482213d541b8804dd.zip
Adding upstream version 86.0.1.upstream/86.0.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'gfx/gl/DecomposeIntoNoRepeatTriangles.cpp')
-rw-r--r--gfx/gl/DecomposeIntoNoRepeatTriangles.cpp128
1 files changed, 128 insertions, 0 deletions
diff --git a/gfx/gl/DecomposeIntoNoRepeatTriangles.cpp b/gfx/gl/DecomposeIntoNoRepeatTriangles.cpp
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "DecomposeIntoNoRepeatTriangles.h"
+#include "gfxMatrix.h"
+
+namespace mozilla {
+namespace gl {
+
+void RectTriangles::AppendRectToCoordArray(nsTArray<coord>& array, GLfloat x0,
+ GLfloat y0, GLfloat x1, GLfloat y1) {
+ coord* v = array.AppendElements(6);
+
+ v[0].x = x0;
+ v[0].y = y0;
+ v[1].x = x1;
+ v[1].y = y0;
+ v[2].x = x0;
+ v[2].y = y1;
+ v[3].x = x0;
+ v[3].y = y1;
+ v[4].x = x1;
+ v[4].y = y0;
+ v[5].x = x1;
+ v[5].y = y1;
+}
+
+void RectTriangles::addRect(GLfloat x0, GLfloat y0, GLfloat x1, GLfloat y1,
+ GLfloat tx0, GLfloat ty0, GLfloat tx1, GLfloat ty1,
+ bool flip_y /* = false */) {
+ if (flip_y) {
+ std::swap(ty0, ty1);
+ }
+ AppendRectToCoordArray(mVertexCoords, x0, y0, x1, y1);
+ AppendRectToCoordArray(mTexCoords, tx0, ty0, tx1, ty1);
+}
+
+static GLfloat WrapTexCoord(GLfloat v) {
+ // This should return values in range [0, 1.0)
+ return v - floorf(v);
+}
+
+void DecomposeIntoNoRepeatTriangles(const gfx::IntRect& aTexCoordRect,
+ const gfx::IntSize& aTexSize,
+ RectTriangles& aRects,
+ bool aFlipY /* = false */) {
+ // normalize this
+ gfx::IntRect tcr(aTexCoordRect);
+ while (tcr.X() >= aTexSize.width) tcr.MoveByX(-aTexSize.width);
+ while (tcr.Y() >= aTexSize.height) tcr.MoveByY(-aTexSize.height);
+
+ // Compute top left and bottom right tex coordinates
+ GLfloat tl[2] = {GLfloat(tcr.X()) / GLfloat(aTexSize.width),
+ GLfloat(tcr.Y()) / GLfloat(aTexSize.height)};
+ GLfloat br[2] = {GLfloat(tcr.XMost()) / GLfloat(aTexSize.width),
+ GLfloat(tcr.YMost()) / GLfloat(aTexSize.height)};
+
+ // then check if we wrap in either the x or y axis; if we do,
+ // then also use fmod to figure out the "true" non-wrapping
+ // texture coordinates.
+
+ bool xwrap = false, ywrap = false;
+ if (tcr.X() < 0 || tcr.X() > aTexSize.width || tcr.XMost() < 0 ||
+ tcr.XMost() > aTexSize.width) {
+ xwrap = true;
+ tl[0] = WrapTexCoord(tl[0]);
+ br[0] = WrapTexCoord(br[0]);
+ }
+
+ if (tcr.Y() < 0 || tcr.Y() > aTexSize.height || tcr.YMost() < 0 ||
+ tcr.YMost() > aTexSize.height) {
+ ywrap = true;
+ tl[1] = WrapTexCoord(tl[1]);
+ br[1] = WrapTexCoord(br[1]);
+ }
+
+ NS_ASSERTION(tl[0] >= 0.0f && tl[0] <= 1.0f && tl[1] >= 0.0f &&
+ tl[1] <= 1.0f && br[0] >= 0.0f && br[0] <= 1.0f &&
+ br[1] >= 0.0f && br[1] <= 1.0f,
+ "Somehow generated invalid texture coordinates");
+
+ // If xwrap is false, the texture will be sampled from tl[0]
+ // .. br[0]. If xwrap is true, then it will be split into tl[0]
+ // .. 1.0, and 0.0 .. br[0]. Same for the Y axis. The
+ // destination rectangle is also split appropriately, according
+ // to the calculated xmid/ymid values.
+
+ // There isn't a 1:1 mapping between tex coords and destination coords;
+ // when computing midpoints, we have to take that into account. We
+ // need to map the texture coords, which are (in the wrap case):
+ // |tl->1| and |0->br| to the |0->1| range of the vertex coords. So
+ // we have the length (1-tl)+(br) that needs to map into 0->1.
+ // These are only valid if there is wrap involved, they won't be used
+ // otherwise.
+ GLfloat xlen = (1.0f - tl[0]) + br[0];
+ GLfloat ylen = (1.0f - tl[1]) + br[1];
+
+ NS_ASSERTION(!xwrap || xlen > 0.0f, "xlen isn't > 0, what's going on?");
+ NS_ASSERTION(!ywrap || ylen > 0.0f, "ylen isn't > 0, what's going on?");
+ NS_ASSERTION(aTexCoordRect.Width() <= aTexSize.width &&
+ aTexCoordRect.Height() <= aTexSize.height,
+ "tex coord rect would cause tiling!");
+
+ if (!xwrap && !ywrap) {
+ aRects.addRect(0.0f, 0.0f, 1.0f, 1.0f, tl[0], tl[1], br[0], br[1], aFlipY);
+ } else if (!xwrap && ywrap) {
+ GLfloat ymid = (1.0f - tl[1]) / ylen;
+ aRects.addRect(0.0f, 0.0f, 1.0f, ymid, tl[0], tl[1], br[0], 1.0f, aFlipY);
+ aRects.addRect(0.0f, ymid, 1.0f, 1.0f, tl[0], 0.0f, br[0], br[1], aFlipY);
+ } else if (xwrap && !ywrap) {
+ GLfloat xmid = (1.0f - tl[0]) / xlen;
+ aRects.addRect(0.0f, 0.0f, xmid, 1.0f, tl[0], tl[1], 1.0f, br[1], aFlipY);
+ aRects.addRect(xmid, 0.0f, 1.0f, 1.0f, 0.0f, tl[1], br[0], br[1], aFlipY);
+ } else {
+ GLfloat xmid = (1.0f - tl[0]) / xlen;
+ GLfloat ymid = (1.0f - tl[1]) / ylen;
+ aRects.addRect(0.0f, 0.0f, xmid, ymid, tl[0], tl[1], 1.0f, 1.0f, aFlipY);
+ aRects.addRect(xmid, 0.0f, 1.0f, ymid, 0.0f, tl[1], br[0], 1.0f, aFlipY);
+ aRects.addRect(0.0f, ymid, xmid, 1.0f, tl[0], 0.0f, 1.0f, br[1], aFlipY);
+ aRects.addRect(xmid, ymid, 1.0f, 1.0f, 0.0f, 0.0f, br[0], br[1], aFlipY);
+ }
+}
+
+} // namespace gl
+} // namespace mozilla