Add normal map sample
This adds an example of an SkShader that does normal
mapping. It has a single directional light and an
ambient light.
Committed: https://skia.googlesource.com/skia/+/8e0da72ba890de395c9946ec6639c9e1e7b16027
Review URL: https://codereview.chromium.org/1212813009
diff --git a/gyp/SampleApp.gyp b/gyp/SampleApp.gyp
index 7ccda93..a1519e5 100644
--- a/gyp/SampleApp.gyp
+++ b/gyp/SampleApp.gyp
@@ -86,6 +86,7 @@
'../samplecode/SampleLayerMask.cpp',
'../samplecode/SampleLayers.cpp',
'../samplecode/SampleLCD.cpp',
+ '../samplecode/SampleLighting.cpp',
'../samplecode/SampleLines.cpp',
'../samplecode/SampleLua.cpp',
'../samplecode/SampleManyRects.cpp',
@@ -259,6 +260,11 @@
'android_deps.gyp:Android_SampleApp',
],
}],
+ [ 'skia_os == "chromeos"', {
+ 'sources!': [
+ '../samplecode/SampleLighting.cpp', #doesn't compile due to gpu dependencies
+ ],
+ }],
[ 'skia_gpu == 1', {
'dependencies': [
'gputest.gyp:skgputest',
diff --git a/resources/brickwork-texture.jpg b/resources/brickwork-texture.jpg
new file mode 100644
index 0000000..9a7dd11
--- /dev/null
+++ b/resources/brickwork-texture.jpg
Binary files differ
diff --git a/resources/brickwork_normal-map.jpg b/resources/brickwork_normal-map.jpg
new file mode 100644
index 0000000..4ff3c3a
--- /dev/null
+++ b/resources/brickwork_normal-map.jpg
Binary files differ
diff --git a/samplecode/SampleLighting.cpp b/samplecode/SampleLighting.cpp
new file mode 100755
index 0000000..40e6fbb
--- /dev/null
+++ b/samplecode/SampleLighting.cpp
@@ -0,0 +1,429 @@
+
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+#include "SampleCode.h"
+#include "Resources.h"
+
+#include "SkCanvas.h"
+#include "SkErrorInternals.h"
+#include "SkGr.h"
+#include "SkReadBuffer.h"
+#include "SkShader.h"
+#include "SkWriteBuffer.h"
+#include "GrFragmentProcessor.h"
+#include "GrCoordTransform.h"
+#include "gl/GrGLProcessor.h"
+#include "gl/builders/GrGLProgramBuilder.h"
+
+///////////////////////////////////////////////////////////////////////////////
+
+struct SkVector3 {
+ SkScalar fX, fY, fZ;
+
+ bool operator==(const SkVector3& other) const {
+ return fX == other.fX && fY == other.fY && fZ == other.fZ;
+ }
+
+ bool operator!=(const SkVector3& other) const {
+ return !(*this == other);
+ }
+};
+
+class LightingShader : public SkShader {
+public:
+ struct Light {
+ SkVector3 fDirection;
+ SkColor fColor; // assumed to be linear color
+ };
+
+ LightingShader(const SkBitmap& diffuse, const SkBitmap& normal, const Light& light,
+ const SkColor ambient)
+ : fDiffuseMap(diffuse)
+ , fNormalMap(normal)
+ , fLight(light)
+ , fAmbientColor(ambient) {}
+
+ SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(LightingShader);
+
+ void flatten(SkWriteBuffer& buf) const override {
+ buf.writeBitmap(fDiffuseMap);
+ buf.writeBitmap(fNormalMap);
+ buf.writeScalarArray(&fLight.fDirection.fX, 3);
+ buf.writeColor(fLight.fColor);
+ buf.writeColor(fAmbientColor);
+ }
+
+ bool asFragmentProcessor(GrContext*, const SkPaint& paint, const SkMatrix& viewM,
+ const SkMatrix* localMatrix, GrColor* color,
+ GrProcessorDataManager*, GrFragmentProcessor** fp) const override;
+
+ SkShader::BitmapType asABitmap(SkBitmap* bitmap, SkMatrix* matrix,
+ SkShader::TileMode* xy) const override {
+ if (bitmap) {
+ *bitmap = fDiffuseMap;
+ }
+ if (matrix) {
+ matrix->reset();
+ }
+ if (xy) {
+ xy[0] = kClamp_TileMode;
+ xy[1] = kClamp_TileMode;
+ }
+ return kDefault_BitmapType;
+ }
+
+#ifndef SK_IGNORE_TO_STRING
+ void toString(SkString* str) const override {
+ str->appendf("LightingShader: ()");
+ }
+#endif
+
+ void setLight(const Light& light) { fLight = light; }
+
+private:
+ SkBitmap fDiffuseMap;
+ SkBitmap fNormalMap;
+ Light fLight;
+ SkColor fAmbientColor;
+};
+
+SkFlattenable* LightingShader::CreateProc(SkReadBuffer& buf) {
+ SkBitmap diffuse;
+ if (!buf.readBitmap(&diffuse)) {
+ return NULL;
+ }
+ diffuse.setImmutable();
+
+ SkBitmap normal;
+ if (!buf.readBitmap(&normal)) {
+ return NULL;
+ }
+ normal.setImmutable();
+
+ Light light;
+ if (!buf.readScalarArray(&light.fDirection.fX, 3)) {
+ return NULL;
+ }
+ light.fColor = buf.readColor();
+
+ SkColor ambient = buf.readColor();
+
+ return SkNEW_ARGS(LightingShader, (diffuse, normal, light, ambient));
+}
+
+////////////////////////////////////////////////////////////////////////////
+
+class LightingFP : public GrFragmentProcessor {
+public:
+ LightingFP(GrTexture* diffuse, GrTexture* normal, const SkMatrix& matrix,
+ SkVector3 lightDir, GrColor lightColor, GrColor ambientColor)
+ : fDeviceTransform(kDevice_GrCoordSet, matrix)
+ , fDiffuseTextureAccess(diffuse)
+ , fNormalTextureAccess(normal)
+ , fLightDir(lightDir)
+ , fLightColor(lightColor)
+ , fAmbientColor(ambientColor) {
+ this->addCoordTransform(&fDeviceTransform);
+ this->addTextureAccess(&fDiffuseTextureAccess);
+ this->addTextureAccess(&fNormalTextureAccess);
+
+ this->initClassID<LightingFP>();
+ }
+
+ class LightingGLFP : public GrGLFragmentProcessor {
+ public:
+ LightingGLFP() : fLightColor(GrColor_ILLEGAL) {
+ fLightDir.fX = 10000.0f;
+ }
+
+ void emitCode(GrGLFPBuilder* builder,
+ const GrFragmentProcessor& fp,
+ const char* outputColor,
+ const char* inputColor,
+ const TransformedCoordsArray& coords,
+ const TextureSamplerArray& samplers) override {
+
+ GrGLFragmentBuilder* fpb = builder->getFragmentShaderBuilder();
+
+ // add uniforms
+ const char* lightDirUniName = NULL;
+ fLightDirUni = builder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
+ kVec3f_GrSLType, kDefault_GrSLPrecision,
+ "LightDir", &lightDirUniName);
+
+ const char* lightColorUniName = NULL;
+ fLightColorUni = builder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
+ kVec4f_GrSLType, kDefault_GrSLPrecision,
+ "LightColor", &lightColorUniName);
+
+ const char* ambientColorUniName = NULL;
+ fAmbientColorUni = builder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
+ kVec4f_GrSLType, kDefault_GrSLPrecision,
+ "AmbientColor", &ambientColorUniName);
+
+ fpb->codeAppend("vec4 diffuseColor = ");
+ fpb->appendTextureLookupAndModulate(inputColor, samplers[0],
+ coords[0].c_str(), coords[0].getType());
+ fpb->codeAppend(";");
+
+ fpb->codeAppend("vec4 normalColor = ");
+ fpb->appendTextureLookup(samplers[1], coords[0].c_str(), coords[0].getType());
+ fpb->codeAppend(";");
+
+ fpb->codeAppend("vec3 normal = normalize(2.0*(normalColor.rgb - vec3(0.5)));");
+ fpb->codeAppendf("vec3 lightDir = normalize(%s);", lightDirUniName);
+ fpb->codeAppend("float NdotL = dot(normal, lightDir);");
+ // diffuse light
+ fpb->codeAppendf("vec3 result = %s.rgb*diffuseColor.rgb*NdotL;", lightColorUniName);
+ // ambient light
+ fpb->codeAppendf("result += %s.rgb;", ambientColorUniName);
+ fpb->codeAppendf("%s = vec4(result.rgb, diffuseColor.a);", outputColor);
+ }
+
+ void setData(const GrGLProgramDataManager& pdman, const GrProcessor& proc) override {
+ const LightingFP& lightingFP = proc.cast<LightingFP>();
+
+ SkVector3 lightDir = lightingFP.lightDir();
+ if (lightDir != fLightDir) {
+ pdman.set3fv(fLightDirUni, 1, &lightDir.fX);
+ fLightDir = lightDir;
+ }
+
+ GrColor lightColor = lightingFP.lightColor();
+ if (lightColor != fLightColor) {
+ GrGLfloat c[4];
+ GrColorToRGBAFloat(lightColor, c);
+ pdman.set4fv(fLightColorUni, 1, c);
+ fLightColor = lightColor;
+ }
+
+ GrColor ambientColor = lightingFP.ambientColor();
+ if (ambientColor != fAmbientColor) {
+ GrGLfloat c[4];
+ GrColorToRGBAFloat(ambientColor, c);
+ pdman.set4fv(fAmbientColorUni, 1, c);
+ fAmbientColor = ambientColor;
+ }
+ }
+
+ static void GenKey(const GrProcessor& proc, const GrGLSLCaps&,
+ GrProcessorKeyBuilder* b) {
+// const LightingFP& lightingFP = proc.cast<LightingFP>();
+ // only one shader generated currently
+ b->add32(0x0);
+ }
+
+ private:
+ SkVector3 fLightDir;
+ GrGLProgramDataManager::UniformHandle fLightDirUni;
+
+ GrColor fLightColor;
+ GrGLProgramDataManager::UniformHandle fLightColorUni;
+
+ GrColor fAmbientColor;
+ GrGLProgramDataManager::UniformHandle fAmbientColorUni;
+ };
+
+ GrGLFragmentProcessor* createGLInstance() const override { return SkNEW(LightingGLFP); }
+
+ void getGLProcessorKey(const GrGLSLCaps& caps, GrProcessorKeyBuilder* b) const override {
+ LightingGLFP::GenKey(*this, caps, b);
+ }
+
+ const char* name() const override { return "LightingFP"; }
+
+ void onComputeInvariantOutput(GrInvariantOutput* inout) const override {
+ inout->mulByUnknownFourComponents();
+ }
+
+ SkVector3 lightDir() const { return fLightDir; }
+ GrColor lightColor() const { return fLightColor; }
+ GrColor ambientColor() const { return fAmbientColor; }
+
+private:
+ bool onIsEqual(const GrFragmentProcessor& proc) const override {
+ const LightingFP& lightingFP = proc.cast<LightingFP>();
+ return fDeviceTransform == lightingFP.fDeviceTransform &&
+ fDiffuseTextureAccess == lightingFP.fDiffuseTextureAccess &&
+ fNormalTextureAccess == lightingFP.fNormalTextureAccess &&
+ fLightDir == lightingFP.fLightDir &&
+ fLightColor == lightingFP.fLightColor &&
+ fAmbientColor == lightingFP.fAmbientColor;
+ }
+
+ GrCoordTransform fDeviceTransform;
+ GrTextureAccess fDiffuseTextureAccess;
+ GrTextureAccess fNormalTextureAccess;
+ SkVector3 fLightDir;
+ GrColor fLightColor;
+ GrColor fAmbientColor;
+};
+
+bool LightingShader::asFragmentProcessor(GrContext* context, const SkPaint& paint,
+ const SkMatrix& viewM, const SkMatrix* localMatrix,
+ GrColor* color, GrProcessorDataManager*,
+ GrFragmentProcessor** fp) const {
+ // we assume diffuse and normal maps have same width and height
+ // TODO: support different sizes
+ SkASSERT(fDiffuseMap.width() == fNormalMap.width() &&
+ fDiffuseMap.height() == fNormalMap.height());
+ SkMatrix matrix;
+ matrix.setIDiv(fDiffuseMap.width(), fDiffuseMap.height());
+
+ SkMatrix lmInverse;
+ if (!this->getLocalMatrix().invert(&lmInverse)) {
+ return false;
+ }
+ if (localMatrix) {
+ SkMatrix inv;
+ if (!localMatrix->invert(&inv)) {
+ return false;
+ }
+ lmInverse.postConcat(inv);
+ }
+ matrix.preConcat(lmInverse);
+
+ // Must set wrap and filter on the sampler before requesting a texture. In two places below
+ // we check the matrix scale factors to determine how to interpret the filter quality setting.
+ // This completely ignores the complexity of the drawVertices case where explicit local coords
+ // are provided by the caller.
+ GrTextureParams::FilterMode textureFilterMode = GrTextureParams::kBilerp_FilterMode;
+ switch (paint.getFilterQuality()) {
+ case kNone_SkFilterQuality:
+ textureFilterMode = GrTextureParams::kNone_FilterMode;
+ break;
+ case kLow_SkFilterQuality:
+ textureFilterMode = GrTextureParams::kBilerp_FilterMode;
+ break;
+ case kMedium_SkFilterQuality:{
+ SkMatrix matrix;
+ matrix.setConcat(viewM, this->getLocalMatrix());
+ if (matrix.getMinScale() < SK_Scalar1) {
+ textureFilterMode = GrTextureParams::kMipMap_FilterMode;
+ } else {
+ // Don't trigger MIP level generation unnecessarily.
+ textureFilterMode = GrTextureParams::kBilerp_FilterMode;
+ }
+ break;
+ }
+ case kHigh_SkFilterQuality:
+ default:
+ SkErrorInternals::SetError(kInvalidPaint_SkError,
+ "Sorry, I don't understand the filtering "
+ "mode you asked for. Falling back to "
+ "MIPMaps.");
+ textureFilterMode = GrTextureParams::kMipMap_FilterMode;
+ break;
+
+ }
+
+ // TODO: support other tile modes
+ GrTextureParams params(kClamp_TileMode, textureFilterMode);
+ SkAutoTUnref<GrTexture> diffuseTexture(GrRefCachedBitmapTexture(context, fDiffuseMap, ¶ms));
+ if (!diffuseTexture) {
+ SkErrorInternals::SetError(kInternalError_SkError,
+ "Couldn't convert bitmap to texture.");
+ return false;
+ }
+
+ SkAutoTUnref<GrTexture> normalTexture(GrRefCachedBitmapTexture(context, fNormalMap, ¶ms));
+ if (!normalTexture) {
+ SkErrorInternals::SetError(kInternalError_SkError,
+ "Couldn't convert bitmap to texture.");
+ return false;
+ }
+
+ GrColor lightColor = GrColorPackRGBA(SkColorGetR(fLight.fColor), SkColorGetG(fLight.fColor),
+ SkColorGetB(fLight.fColor), SkColorGetA(fLight.fColor));
+ GrColor ambientColor = GrColorPackRGBA(SkColorGetR(fAmbientColor), SkColorGetG(fAmbientColor),
+ SkColorGetB(fAmbientColor), SkColorGetA(fAmbientColor));
+
+ *fp = SkNEW_ARGS(LightingFP, (diffuseTexture, normalTexture, matrix,
+ fLight.fDirection, lightColor, ambientColor));
+ *color = GrColorPackA4(paint.getAlpha());
+ return true;
+}
+
+////////////////////////////////////////////////////////////////////////////
+
+class LightingView : public SampleView {
+public:
+ SkAutoTUnref<LightingShader> fShader;
+ SkBitmap fDiffuseBitmap;
+ SkBitmap fNormalBitmap;
+ SkScalar fLightAngle;
+ int fColorFactor;
+
+ LightingView() {
+ SkString diffusePath = GetResourcePath("brickwork-texture.jpg");
+ SkImageDecoder::DecodeFile(diffusePath.c_str(), &fDiffuseBitmap);
+ SkString normalPath = GetResourcePath("brickwork_normal-map.jpg");
+ SkImageDecoder::DecodeFile(normalPath.c_str(), &fNormalBitmap);
+
+ fLightAngle = 0.0f;
+ fColorFactor = 0;
+
+ LightingShader::Light light;
+ light.fColor = SkColorSetRGB(0xff, 0xff, 0xff);
+ light.fDirection.fX = SkScalarSin(fLightAngle)*SkScalarSin(SK_ScalarPI*0.25f);
+ light.fDirection.fY = SkScalarCos(fLightAngle)*SkScalarSin(SK_ScalarPI*0.25f);
+ light.fDirection.fZ = SkScalarCos(SK_ScalarPI*0.25f);
+
+ SkColor ambient = SkColorSetRGB(0x1f, 0x1f, 0x1f);
+
+ fShader.reset(SkNEW_ARGS(LightingShader, (fDiffuseBitmap, fNormalBitmap, light, ambient)));
+ }
+
+ virtual ~LightingView() {}
+
+protected:
+ // overrides from SkEventSink
+ bool onQuery(SkEvent* evt) override {
+ if (SampleCode::TitleQ(*evt)) {
+ SampleCode::TitleR(evt, "Lighting");
+ return true;
+ }
+ return this->INHERITED::onQuery(evt);
+ }
+
+ void onDrawContent(SkCanvas* canvas) override {
+ fLightAngle += 0.015f;
+ fColorFactor++;
+
+ LightingShader::Light light;
+ light.fColor = SkColorSetRGB(0xff, 0xff, (fColorFactor >> 1) & 0xff);
+ light.fDirection.fX = SkScalarSin(fLightAngle)*SkScalarSin(SK_ScalarPI*0.25f);
+ light.fDirection.fY = SkScalarCos(fLightAngle)*SkScalarSin(SK_ScalarPI*0.25f);
+ light.fDirection.fZ = SkScalarCos(SK_ScalarPI*0.25f);
+
+ fShader.get()->setLight(light);
+
+ SkPaint paint;
+ paint.setShader(fShader);
+ paint.setColor(SK_ColorBLACK);
+
+ SkRect r = SkRect::MakeWH((SkScalar)fDiffuseBitmap.width(),
+ (SkScalar)fDiffuseBitmap.height());
+ canvas->drawRect(r, paint);
+
+ // so we're constantly updating
+ this->inval(NULL);
+ }
+
+ SkView::Click* onFindClickHandler(SkScalar x, SkScalar y, unsigned modi) override {
+ this->inval(NULL);
+ return this->INHERITED::onFindClickHandler(x, y, modi);
+ }
+
+private:
+ typedef SampleView INHERITED;
+};
+
+//////////////////////////////////////////////////////////////////////////////
+
+static SkView* MyFactory() { return new LightingView; }
+static SkViewRegister reg(MyFactory);
