diff options
Diffstat (limited to 'android/source/src/java/org/mozilla/gecko/gfx/ScrollbarLayer.java')
| -rw-r--r-- | android/source/src/java/org/mozilla/gecko/gfx/ScrollbarLayer.java | 451 |
1 files changed, 451 insertions, 0 deletions
diff --git a/android/source/src/java/org/mozilla/gecko/gfx/ScrollbarLayer.java b/android/source/src/java/org/mozilla/gecko/gfx/ScrollbarLayer.java new file mode 100644 index 000000000..7ef8ff020 --- /dev/null +++ b/android/source/src/java/org/mozilla/gecko/gfx/ScrollbarLayer.java @@ -0,0 +1,451 @@ +/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*- + * 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/. */ + +package org.mozilla.gecko.gfx; + +import android.graphics.Bitmap; +import android.graphics.Canvas; +import android.graphics.Color; +import android.graphics.Paint; +import android.graphics.PorterDuff; +import android.graphics.Rect; +import android.graphics.RectF; +import android.opengl.GLES20; + +import org.libreoffice.kit.DirectBufferAllocator; +import org.mozilla.gecko.util.FloatUtils; + +import java.nio.ByteBuffer; +import java.nio.FloatBuffer; + +/** + * Draws a small rect. This is scaled to become a scrollbar. + */ +public class ScrollbarLayer extends TileLayer { + private static String LOGTAG = LayerView.class.getName(); + public static final long FADE_DELAY = 500; // milliseconds before fade-out starts + private static final float FADE_AMOUNT = 0.03f; // how much (as a percent) the scrollbar should fade per frame + + private static final int PADDING = 1; // gap between scrollbar and edge of viewport + private static final int BAR_SIZE = 6; + private static final int CAP_RADIUS = (BAR_SIZE / 2); + + private final boolean mVertical; + private final Bitmap mBitmap; + private final Canvas mCanvas; + private float mOpacity; + + private LayerRenderer mRenderer; + private int mProgram; + private int mPositionHandle; + private int mTextureHandle; + private int mSampleHandle; + private int mTMatrixHandle; + private int mOpacityHandle; + + // Fragment shader used to draw the scroll-bar with opacity + private static final String FRAGMENT_SHADER = + "precision mediump float;\n" + + "varying vec2 vTexCoord;\n" + + "uniform sampler2D sTexture;\n" + + "uniform float uOpacity;\n" + + "void main() {\n" + + " gl_FragColor = texture2D(sTexture, vec2(vTexCoord.x, 1.0 - vTexCoord.y));\n" + + " gl_FragColor.a *= uOpacity;\n" + + "}\n"; + + // Dimensions of the texture image + private static final float TEX_HEIGHT = 8.0f; + private static final float TEX_WIDTH = 8.0f; + + // Texture coordinates for the scrollbar's body + // We take a 1x1 pixel from the center of the image and scale it to become the bar + private static final float[] BODY_TEX_COORDS = { + // x, y + CAP_RADIUS/TEX_WIDTH, CAP_RADIUS/TEX_HEIGHT, + CAP_RADIUS/TEX_WIDTH, (CAP_RADIUS+1)/TEX_HEIGHT, + (CAP_RADIUS+1)/TEX_WIDTH, CAP_RADIUS/TEX_HEIGHT, + (CAP_RADIUS+1)/TEX_WIDTH, (CAP_RADIUS+1)/TEX_HEIGHT + }; + + // Texture coordinates for the top cap of the scrollbar + private static final float[] TOP_CAP_TEX_COORDS = { + // x, y + 0 , 1.0f - CAP_RADIUS/TEX_HEIGHT, + 0 , 1.0f, + BAR_SIZE/TEX_WIDTH, 1.0f - CAP_RADIUS/TEX_HEIGHT, + BAR_SIZE/TEX_WIDTH, 1.0f + }; + + // Texture coordinates for the bottom cap of the scrollbar + private static final float[] BOT_CAP_TEX_COORDS = { + // x, y + 0 , 1.0f - BAR_SIZE/TEX_HEIGHT, + 0 , 1.0f - CAP_RADIUS/TEX_HEIGHT, + BAR_SIZE/TEX_WIDTH, 1.0f - BAR_SIZE/TEX_HEIGHT, + BAR_SIZE/TEX_WIDTH, 1.0f - CAP_RADIUS/TEX_HEIGHT + }; + + // Texture coordinates for the left cap of the scrollbar + private static final float[] LEFT_CAP_TEX_COORDS = { + // x, y + 0 , 1.0f - BAR_SIZE/TEX_HEIGHT, + 0 , 1.0f, + CAP_RADIUS/TEX_WIDTH, 1.0f - BAR_SIZE/TEX_HEIGHT, + CAP_RADIUS/TEX_WIDTH, 1.0f + }; + + // Texture coordinates for the right cap of the scrollbar + private static final float[] RIGHT_CAP_TEX_COORDS = { + // x, y + CAP_RADIUS/TEX_WIDTH, 1.0f - BAR_SIZE/TEX_HEIGHT, + CAP_RADIUS/TEX_WIDTH, 1.0f, + BAR_SIZE/TEX_WIDTH , 1.0f - BAR_SIZE/TEX_HEIGHT, + BAR_SIZE/TEX_WIDTH , 1.0f + }; + + private ScrollbarLayer(LayerRenderer renderer, CairoImage image, boolean vertical, ByteBuffer buffer) { + super(image, TileLayer.PaintMode.NORMAL); + mVertical = vertical; + mRenderer = renderer; + + IntSize size = image.getSize(); + mBitmap = Bitmap.createBitmap(size.width, size.height, Bitmap.Config.ARGB_8888); + mCanvas = new Canvas(mBitmap); + + // Paint a spot to use as the scroll indicator + Paint foregroundPaint = new Paint(); + foregroundPaint.setAntiAlias(true); + foregroundPaint.setStyle(Paint.Style.FILL); + foregroundPaint.setColor(Color.argb(127, 0, 0, 0)); + + mCanvas.drawColor(Color.argb(0, 0, 0, 0), PorterDuff.Mode.CLEAR); + mCanvas.drawCircle(CAP_RADIUS, CAP_RADIUS, CAP_RADIUS, foregroundPaint); + + mBitmap.copyPixelsToBuffer(buffer.asIntBuffer()); + } + + public static ScrollbarLayer create(LayerRenderer renderer, boolean vertical) { + // just create an empty image for now, it will get drawn + // on demand anyway + int imageSize = IntSize.nextPowerOfTwo(BAR_SIZE); + ByteBuffer buffer = DirectBufferAllocator.allocate(imageSize * imageSize * 4); + CairoImage image = new BufferedCairoImage(buffer, imageSize, imageSize, + CairoImage.FORMAT_ARGB32); + return new ScrollbarLayer(renderer, image, vertical, buffer); + } + + private void createProgram() { + int vertexShader = LayerRenderer.loadShader(GLES20.GL_VERTEX_SHADER, + LayerRenderer.DEFAULT_VERTEX_SHADER); + int fragmentShader = LayerRenderer.loadShader(GLES20.GL_FRAGMENT_SHADER, + FRAGMENT_SHADER); + + mProgram = GLES20.glCreateProgram(); + GLES20.glAttachShader(mProgram, vertexShader); // add the vertex shader to program + GLES20.glAttachShader(mProgram, fragmentShader); // add the fragment shader to program + GLES20.glLinkProgram(mProgram); // creates OpenGL program executables + + // Get handles to the shaders' vPosition, aTexCoord, sTexture, and uTMatrix members. + mPositionHandle = GLES20.glGetAttribLocation(mProgram, "vPosition"); + mTextureHandle = GLES20.glGetAttribLocation(mProgram, "aTexCoord"); + mSampleHandle = GLES20.glGetUniformLocation(mProgram, "sTexture"); + mTMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uTMatrix"); + mOpacityHandle = GLES20.glGetUniformLocation(mProgram, "uOpacity"); + } + + private void activateProgram() { + // Add the program to the OpenGL environment + GLES20.glUseProgram(mProgram); + + // Set the transformation matrix + GLES20.glUniformMatrix4fv(mTMatrixHandle, 1, false, + LayerRenderer.DEFAULT_TEXTURE_MATRIX, 0); + + // Enable the arrays from which we get the vertex and texture coordinates + GLES20.glEnableVertexAttribArray(mPositionHandle); + GLES20.glEnableVertexAttribArray(mTextureHandle); + + GLES20.glUniform1i(mSampleHandle, 0); + GLES20.glUniform1f(mOpacityHandle, mOpacity); + } + + private void deactivateProgram() { + GLES20.glDisableVertexAttribArray(mTextureHandle); + GLES20.glDisableVertexAttribArray(mPositionHandle); + GLES20.glUseProgram(0); + } + + /** + * Decrease the opacity of the scrollbar by one frame's worth. + * Return true if the opacity was decreased, or false if the scrollbars + * are already fully faded out. + */ + public boolean fade() { + if (FloatUtils.fuzzyEquals(mOpacity, 0.0f)) { + return false; + } + beginTransaction(); // called on compositor thread + mOpacity = Math.max(mOpacity - FADE_AMOUNT, 0.0f); + endTransaction(); + return true; + } + + /** + * Restore the opacity of the scrollbar to fully opaque. + * Return true if the opacity was changed, or false if the scrollbars + * are already fully opaque. + */ + public boolean unfade() { + if (FloatUtils.fuzzyEquals(mOpacity, 1.0f)) { + return false; + } + beginTransaction(); // called on compositor thread + mOpacity = 1.0f; + endTransaction(); + + return true; + } + + @Override + public void draw(RenderContext context) { + if (!initialized()) + return; + + // Create the shader program, if necessary + if (mProgram == 0) { + createProgram(); + } + + // Enable the shader program + mRenderer.deactivateDefaultProgram(); + activateProgram(); + + GLES20.glEnable(GLES20.GL_BLEND); + GLES20.glBlendFunc(GLES20.GL_SRC_ALPHA, GLES20.GL_ONE_MINUS_SRC_ALPHA); + + Rect rect = RectUtils.round(mVertical + ? getVerticalRect(context) + : getHorizontalRect(context)); + GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, getTextureID()); + + float viewWidth = context.viewport.width(); + float viewHeight = context.viewport.height(); + + float top = viewHeight - rect.top; + float bot = viewHeight - rect.bottom; + + // Coordinates for the scrollbar's body combined with the texture coordinates + float[] bodyCoords = { + // x, y, z, texture_x, texture_y + rect.left/viewWidth, bot/viewHeight, 0, + BODY_TEX_COORDS[0], BODY_TEX_COORDS[1], + + rect.left/viewWidth, (bot+rect.height())/viewHeight, 0, + BODY_TEX_COORDS[2], BODY_TEX_COORDS[3], + + (rect.left+rect.width())/viewWidth, bot/viewHeight, 0, + BODY_TEX_COORDS[4], BODY_TEX_COORDS[5], + + (rect.left+rect.width())/viewWidth, (bot+rect.height())/viewHeight, 0, + BODY_TEX_COORDS[6], BODY_TEX_COORDS[7] + }; + + // Get the buffer and handles from the context + FloatBuffer coordBuffer = context.coordBuffer; + int positionHandle = mPositionHandle; + int textureHandle = mTextureHandle; + + // Make sure we are at position zero in the buffer in case other draw methods did not + // clean up after themselves + coordBuffer.position(0); + coordBuffer.put(bodyCoords); + + // Unbind any the current array buffer so we can use client side buffers + GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, 0); + + // Vertex coordinates are x,y,z starting at position 0 into the buffer. + coordBuffer.position(0); + GLES20.glVertexAttribPointer(positionHandle, 3, GLES20.GL_FLOAT, false, 20, + coordBuffer); + + // Texture coordinates are texture_x, texture_y starting at position 3 into the buffer. + coordBuffer.position(3); + GLES20.glVertexAttribPointer(textureHandle, 2, GLES20.GL_FLOAT, false, 20, + coordBuffer); + + GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4); + + // Reset the position in the buffer for the next set of vertex and texture coordinates. + coordBuffer.position(0); + + if (mVertical) { + // top endcap + float[] topCap = { + // x, y, z, texture_x, texture_y + rect.left/viewWidth, top/viewHeight, 0, + TOP_CAP_TEX_COORDS[0], TOP_CAP_TEX_COORDS[1], + + rect.left/viewWidth, (top+CAP_RADIUS)/viewHeight, 0, + TOP_CAP_TEX_COORDS[2], TOP_CAP_TEX_COORDS[3], + + (rect.left+BAR_SIZE)/viewWidth, top/viewHeight, 0, + TOP_CAP_TEX_COORDS[4], TOP_CAP_TEX_COORDS[5], + + (rect.left+BAR_SIZE)/viewWidth, (top+CAP_RADIUS)/viewHeight, 0, + TOP_CAP_TEX_COORDS[6], TOP_CAP_TEX_COORDS[7] + }; + + coordBuffer.put(topCap); + + // Vertex coordinates are x,y,z starting at position 0 into the buffer. + coordBuffer.position(0); + GLES20.glVertexAttribPointer(positionHandle, 3, GLES20.GL_FLOAT, false, 20, + coordBuffer); + + // Texture coordinates are texture_x, texture_y starting at position 3 into the + // buffer. + coordBuffer.position(3); + GLES20.glVertexAttribPointer(textureHandle, 2, GLES20.GL_FLOAT, false, 20, + coordBuffer); + + GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4); + + // Reset the position in the buffer for the next set of vertex and texture + // coordinates. + coordBuffer.position(0); + + // bottom endcap + float[] botCap = { + // x, y, z, texture_x, texture_y + rect.left/viewWidth, (bot-CAP_RADIUS)/viewHeight, 0, + BOT_CAP_TEX_COORDS[0], BOT_CAP_TEX_COORDS[1], + + rect.left/viewWidth, (bot)/viewHeight, 0, + BOT_CAP_TEX_COORDS[2], BOT_CAP_TEX_COORDS[3], + + (rect.left+BAR_SIZE)/viewWidth, (bot-CAP_RADIUS)/viewHeight, 0, + BOT_CAP_TEX_COORDS[4], BOT_CAP_TEX_COORDS[5], + + (rect.left+BAR_SIZE)/viewWidth, (bot)/viewHeight, 0, + BOT_CAP_TEX_COORDS[6], BOT_CAP_TEX_COORDS[7] + }; + + coordBuffer.put(botCap); + + // Vertex coordinates are x,y,z starting at position 0 into the buffer. + coordBuffer.position(0); + GLES20.glVertexAttribPointer(positionHandle, 3, GLES20.GL_FLOAT, false, 20, + coordBuffer); + + // Texture coordinates are texture_x, texture_y starting at position 3 into the + // buffer. + coordBuffer.position(3); + GLES20.glVertexAttribPointer(textureHandle, 2, GLES20.GL_FLOAT, false, 20, + coordBuffer); + + GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4); + + // Reset the position in the buffer for the next set of vertex and texture + // coordinates. + coordBuffer.position(0); + } else { + // left endcap + float[] leftCap = { + // x, y, z, texture_x, texture_y + (rect.left-CAP_RADIUS)/viewWidth, bot/viewHeight, 0, + LEFT_CAP_TEX_COORDS[0], LEFT_CAP_TEX_COORDS[1], + (rect.left-CAP_RADIUS)/viewWidth, (bot+BAR_SIZE)/viewHeight, 0, + LEFT_CAP_TEX_COORDS[2], LEFT_CAP_TEX_COORDS[3], + (rect.left)/viewWidth, bot/viewHeight, 0, LEFT_CAP_TEX_COORDS[4], + LEFT_CAP_TEX_COORDS[5], + (rect.left)/viewWidth, (bot+BAR_SIZE)/viewHeight, 0, + LEFT_CAP_TEX_COORDS[6], LEFT_CAP_TEX_COORDS[7] + }; + + coordBuffer.put(leftCap); + + // Vertex coordinates are x,y,z starting at position 0 into the buffer. + coordBuffer.position(0); + GLES20.glVertexAttribPointer(positionHandle, 3, GLES20.GL_FLOAT, false, 20, + coordBuffer); + + // Texture coordinates are texture_x, texture_y starting at position 3 into the + // buffer. + coordBuffer.position(3); + GLES20.glVertexAttribPointer(textureHandle, 2, GLES20.GL_FLOAT, false, 20, + coordBuffer); + + GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4); + + // Reset the position in the buffer for the next set of vertex and texture + // coordinates. + coordBuffer.position(0); + + // right endcap + float[] rightCap = { + // x, y, z, texture_x, texture_y + rect.right/viewWidth, (bot)/viewHeight, 0, + RIGHT_CAP_TEX_COORDS[0], RIGHT_CAP_TEX_COORDS[1], + + rect.right/viewWidth, (bot+BAR_SIZE)/viewHeight, 0, + RIGHT_CAP_TEX_COORDS[2], RIGHT_CAP_TEX_COORDS[3], + + (rect.right+CAP_RADIUS)/viewWidth, (bot)/viewHeight, 0, + RIGHT_CAP_TEX_COORDS[4], RIGHT_CAP_TEX_COORDS[5], + + (rect.right+CAP_RADIUS)/viewWidth, (bot+BAR_SIZE)/viewHeight, 0, + RIGHT_CAP_TEX_COORDS[6], RIGHT_CAP_TEX_COORDS[7] + }; + + coordBuffer.put(rightCap); + + // Vertex coordinates are x,y,z starting at position 0 into the buffer. + coordBuffer.position(0); + GLES20.glVertexAttribPointer(positionHandle, 3, GLES20.GL_FLOAT, false, 20, + coordBuffer); + + // Texture coordinates are texture_x, texture_y starting at position 3 into the + // buffer. + coordBuffer.position(3); + GLES20.glVertexAttribPointer(textureHandle, 2, GLES20.GL_FLOAT, false, 20, + coordBuffer); + + GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4); + } + + // Enable the default shader program again + deactivateProgram(); + mRenderer.activateDefaultProgram(); + } + + private RectF getVerticalRect(RenderContext context) { + RectF viewport = context.viewport; + RectF pageRect = context.pageRect; + float barStart = ((viewport.top - pageRect.top) * (viewport.height() / pageRect.height())) + CAP_RADIUS; + float barEnd = ((viewport.bottom - pageRect.top) * (viewport.height() / pageRect.height())) - CAP_RADIUS; + if (barStart > barEnd) { + float middle = (barStart + barEnd) / 2.0f; + barStart = barEnd = middle; + } + float right = viewport.width() - PADDING; + return new RectF(right - BAR_SIZE, barStart, right, barEnd); + } + + private RectF getHorizontalRect(RenderContext context) { + RectF viewport = context.viewport; + RectF pageRect = context.pageRect; + float barStart = ((viewport.left - pageRect.left) * (viewport.width() / pageRect.width())) + CAP_RADIUS; + float barEnd = ((viewport.right - pageRect.left) * (viewport.width() / pageRect.width())) - CAP_RADIUS; + if (barStart > barEnd) { + float middle = (barStart + barEnd) / 2.0f; + barStart = barEnd = middle; + } + float bottom = viewport.height() - PADDING; + return new RectF(barStart, bottom - BAR_SIZE, barEnd, bottom); + } +} + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |