Initial text support in new reorderer/renderer

Removes obsolete drawPosText codepath, and unifies text decoration behavior.

Change-Id: I9c563249ab688a3394445a0e7fe1b9d0661f6f7c
diff --git a/libs/hwui/BakedOpRenderer.cpp b/libs/hwui/BakedOpRenderer.cpp
index d2d3285..d13d7ef 100644
--- a/libs/hwui/BakedOpRenderer.cpp
+++ b/libs/hwui/BakedOpRenderer.cpp
@@ -24,6 +24,9 @@
 #include "utils/GLUtils.h"
 #include "VertexBuffer.h"
 
+#include <algorithm>
+#include <math.h>
+
 namespace android {
 namespace uirenderer {
 
@@ -183,6 +186,10 @@
     renderer.renderGlop(state, glop);
 }
 
+void BakedOpDispatcher::onLinesOp(BakedOpRenderer& renderer, const LinesOp& op, const BakedOpState& state) {
+    LOG_ALWAYS_FATAL("todo");
+}
+
 void BakedOpDispatcher::onRectOp(BakedOpRenderer& renderer, const RectOp& op, const BakedOpState& state) {
     Glop glop;
     GlopBuilder(renderer.renderState(), renderer.caches(), &glop)
@@ -270,6 +277,91 @@
     renderer.renderGlop(state, glop);
 }
 
+static void renderTextShadow(BakedOpRenderer& renderer, FontRenderer& fontRenderer,
+        const TextOp& op, const BakedOpState& state) {
+    renderer.caches().textureState().activateTexture(0);
+
+    PaintUtils::TextShadow textShadow;
+    if (!PaintUtils::getTextShadow(op.paint, &textShadow)) {
+        LOG_ALWAYS_FATAL("failed to query shadow attributes");
+    }
+
+    renderer.caches().dropShadowCache.setFontRenderer(fontRenderer);
+    ShadowTexture* texture = renderer.caches().dropShadowCache.get(
+            op.paint, (const char*) op.glyphs,
+            op.glyphCount, textShadow.radius, op.positions);
+    // If the drop shadow exceeds the max texture size or couldn't be
+    // allocated, skip drawing
+    if (!texture) return;
+    const AutoTexture autoCleanup(texture);
+
+    const float sx = op.x - texture->left + textShadow.dx;
+    const float sy = op.y - texture->top + textShadow.dy;
+
+    Glop glop;
+    GlopBuilder(renderer.renderState(), renderer.caches(), &glop)
+            .setRoundRectClipState(state.roundRectClipState)
+            .setMeshTexturedUnitQuad(nullptr)
+            .setFillShadowTexturePaint(*texture, textShadow.color, *op.paint, state.alpha)
+            .setTransform(state.computedState.transform, TransformFlags::None)
+            .setModelViewMapUnitToRect(Rect(sx, sy, sx + texture->width, sy + texture->height))
+            .build();
+    renderer.renderGlop(state, glop);
+}
+
+void BakedOpDispatcher::onTextOp(BakedOpRenderer& renderer, const TextOp& op, const BakedOpState& state) {
+    FontRenderer& fontRenderer = renderer.caches().fontRenderer.getFontRenderer();
+
+    if (CC_UNLIKELY(PaintUtils::hasTextShadow(op.paint))) {
+        fontRenderer.setFont(op.paint, SkMatrix::I());
+        renderTextShadow(renderer, fontRenderer, op, state);
+    }
+
+    float x = op.x;
+    float y = op.y;
+    const Matrix4& transform = state.computedState.transform;
+    const bool pureTranslate = transform.isPureTranslate();
+    if (CC_LIKELY(pureTranslate)) {
+        x = floorf(x + transform.getTranslateX() + 0.5f);
+        y = floorf(y + transform.getTranslateY() + 0.5f);
+        fontRenderer.setFont(op.paint, SkMatrix::I());
+        fontRenderer.setTextureFiltering(false);
+    } else if (CC_UNLIKELY(transform.isPerspective())) {
+        fontRenderer.setFont(op.paint, SkMatrix::I());
+        fontRenderer.setTextureFiltering(true);
+    } else {
+        // We only pass a partial transform to the font renderer. That partial
+        // matrix defines how glyphs are rasterized. Typically we want glyphs
+        // to be rasterized at their final size on screen, which means the partial
+        // matrix needs to take the scale factor into account.
+        // When a partial matrix is used to transform glyphs during rasterization,
+        // the mesh is generated with the inverse transform (in the case of scale,
+        // the mesh is generated at 1.0 / scale for instance.) This allows us to
+        // apply the full transform matrix at draw time in the vertex shader.
+        // Applying the full matrix in the shader is the easiest way to handle
+        // rotation and perspective and allows us to always generated quads in the
+        // font renderer which greatly simplifies the code, clipping in particular.
+        float sx, sy;
+        transform.decomposeScale(sx, sy);
+        fontRenderer.setFont(op.paint, SkMatrix::MakeScale(
+                roundf(std::max(1.0f, sx)),
+                roundf(std::max(1.0f, sy))));
+        fontRenderer.setTextureFiltering(true);
+    }
+
+    // TODO: Implement better clipping for scaled/rotated text
+    const Rect* clip = !pureTranslate ? nullptr : &state.computedState.clipRect;
+    Rect layerBounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
+
+    int alpha = PaintUtils::getAlphaDirect(op.paint) * state.alpha;
+    SkXfermode::Mode mode = PaintUtils::getXfermodeDirect(op.paint);
+    TextDrawFunctor functor(&renderer, &state, x, y, pureTranslate, alpha, mode, op.paint);
+
+    bool hasActiveLayer = false; // TODO
+    fontRenderer.renderPosText(op.paint, clip, (const char*) op.glyphs, op.glyphCount, x, y,
+            op.positions, hasActiveLayer ? &layerBounds : nullptr, &functor, true); // TODO: merging
+}
+
 void BakedOpDispatcher::onLayerOp(BakedOpRenderer& renderer, const LayerOp& op, const BakedOpState& state) {
     OffscreenBuffer* buffer = *op.layerHandle;