Shadow mapping implementation

Partially works, but mostly doesn't.

Change-Id: I415833d07148d2aeae64c0c311e14766ab29ad5e
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@digia.com>

5 files changed, 32 insertions, 27 deletions

diff --git a/src/datavis3d/utils/camerahelper.cpp b/src/datavis3d/utils/camerahelper.cpp
index 7e9b7def..2e868cac 100644
--- a/src/datavis3d/utils/camerahelper.cpp
+++ b/src/datavis3d/utils/camerahelper.cpp
@@ -54,12 +54,12 @@ QVector3D m_up = QVector3D(0, 1, 0);
 
 QPoint m_previousMousePos(0, 0);
 
-float m_xRotation = 0;
-float m_yRotation = 0;
-float m_defaultXRotation = 0;
-float m_defaultYRotation = 0;
+GLfloat m_xRotation = 0;
+GLfloat m_yRotation = 0;
+GLfloat m_defaultXRotation = 0;
+GLfloat m_defaultYRotation = 0;
 
-float m_rotationSpeed = 100;
+GLfloat m_rotationSpeed = 100;
 
 // FUNCTIONS
 void CameraHelper::setRotationSpeed(int speed)
@@ -91,9 +91,9 @@ QMatrix4x4 CameraHelper::calculateViewMatrix(const QPoint &mousePos, int zoom,
     QMatrix4x4 viewMatrix;
 
     // Calculate mouse movement since last frame
-    float mouseMoveX = float(m_previousMousePos.x() - mousePos.x())
+    GLfloat mouseMoveX = GLfloat(m_previousMousePos.x() - mousePos.x())
             / (screenWidth / m_rotationSpeed);
-    float mouseMoveY = float(m_previousMousePos.y() - mousePos.y())
+    GLfloat mouseMoveY = GLfloat(m_previousMousePos.y() - mousePos.y())
             / (screenHeight / m_rotationSpeed);
     // Apply to rotations
     m_xRotation -= mouseMoveX;
@@ -117,7 +117,7 @@ QMatrix4x4 CameraHelper::calculateViewMatrix(const QPoint &mousePos, int zoom,
     // y rotation is always "clean"
     viewMatrix.rotate(m_yRotation, 1.0f, 0.0f, 0.0f);
     // handle zoom by scaling
-    viewMatrix.scale((float)zoom / 100.0f);
+    viewMatrix.scale((GLfloat)zoom / 100.0f);
     // Compensate for translation (if m_target is off origin)
     viewMatrix.translate(-m_target.x(), -m_target.y(), -m_target.z());
     //qDebug() << m_xRotation << m_yRotation;
@@ -131,12 +131,14 @@ QMatrix4x4 CameraHelper::calculateViewMatrix(const QPoint &mousePos, int zoom,
     return viewMatrix;
 }
 
-QVector3D CameraHelper::calculateLightPosition(const QVector3D &lightPosition, float fixedRotation)
+QVector3D CameraHelper::calculateLightPosition(const QVector3D &lightPosition,
+                                               GLfloat fixedRotation, GLfloat distanceModifier)
 {
     // Move light with camera
     QVector3D newLightPosition;
-    float xAngle;
-    float yAngle;
+    GLfloat radiusFactor = lightPosition.z() * (1.5f + distanceModifier); // for making sure light is outside the scene at its lowest point
+    GLfloat xAngle;
+    GLfloat yAngle;
     if (!fixedRotation) {
         xAngle = m_xRotation * m_pi / 180.0f;
         yAngle = m_yRotation * m_pi / 180.0f;
@@ -144,10 +146,10 @@ QVector3D CameraHelper::calculateLightPosition(const QVector3D &lightPosition, f
         xAngle = fixedRotation * m_pi / 180.0f;
         yAngle = 0;
     }
-    float radius = lightPosition.y() * 2.0f; // set radius to match the highest height of the light
-    float zPos = radius * cos(xAngle) * cos(yAngle);
-    float xPos = radius * sin(xAngle) * cos(yAngle);
-    float yPos = lightPosition.y() * sin(yAngle);
+    GLfloat radius = (radiusFactor + lightPosition.y()); // set radius to match the highest height of the light
+    GLfloat zPos = radius * cos(xAngle) * cos(yAngle);
+    GLfloat xPos = radius * sin(xAngle) * cos(yAngle);
+    GLfloat yPos = (radiusFactor + lightPosition.y()) * sin(yAngle);
     // Keep light in the set position in relation to camera
     // TODO: Does not work perfectly yet; Light seems wrong when viewing scene from sides (or isometrically)
     newLightPosition = QVector3D(-xPos + lightPosition.x(),
diff --git a/src/datavis3d/utils/camerahelper_p.h b/src/datavis3d/utils/camerahelper_p.h
index e63061a2..68e7e5a2 100644
--- a/src/datavis3d/utils/camerahelper_p.h
+++ b/src/datavis3d/utils/camerahelper_p.h
@@ -82,7 +82,8 @@ class CameraHelper
     // Calcluate light position based on rotation. Call after calling calculateViewMatrix to get
     // up-to-date position
     static QVector3D calculateLightPosition(const QVector3D &lightPosition,
-                                            float fixedRotation = 0.0f);
+                                            GLfloat fixedRotation = 0.0f,
+                                            GLfloat distanceModifier = 0.0f);
     static void updateMousePos(const QPoint &mousePos);
     static void setCameraPreset(CameraPreset preset);
 };
diff --git a/src/datavis3d/utils/shaderhelper.cpp b/src/datavis3d/utils/shaderhelper.cpp
index 86b3d964..f08daff0 100644
--- a/src/datavis3d/utils/shaderhelper.cpp
+++ b/src/datavis3d/utils/shaderhelper.cpp
@@ -92,7 +92,7 @@ void ShaderHelper::initialize()
     m_viewMatrixUniform = m_program->uniformLocation("V");
     m_modelMatrixUniform = m_program->uniformLocation("M");
     m_invTransModelMatrixUniform = m_program->uniformLocation("itM");
-    m_depthBiasMatrixUniform = m_program->uniformLocation("depthBiasMVP");
+    m_depthMatrixUniform = m_program->uniformLocation("depthMVP");
     m_lightPositionUniform = m_program->uniformLocation("lightPosition_wrld");
     m_lightStrengthUniform = m_program->uniformLocation("lightStrength");
     m_ambientStrengthUniform = m_program->uniformLocation("ambientStrength");
@@ -169,7 +169,7 @@ GLuint ShaderHelper::depth()
 {
     if (!m_initialized)
         qFatal("Shader not initialized");
-    return m_depthBiasMatrixUniform;
+    return m_depthMatrixUniform;
 }
 
 GLuint ShaderHelper::lightP()
diff --git a/src/datavis3d/utils/shaderhelper_p.h b/src/datavis3d/utils/shaderhelper_p.h
index 42c5e9af..d1c72ba5 100644
--- a/src/datavis3d/utils/shaderhelper_p.h
+++ b/src/datavis3d/utils/shaderhelper_p.h
@@ -114,7 +114,7 @@ class ShaderHelper
     GLuint m_viewMatrixUniform;
     GLuint m_modelMatrixUniform;
     GLuint m_invTransModelMatrixUniform;
-    GLuint m_depthBiasMatrixUniform;
+    GLuint m_depthMatrixUniform;
     GLuint m_mvpMatrixUniform;
     GLuint m_lightPositionUniform;
     GLuint m_lightStrengthUniform;
diff --git a/src/datavis3d/utils/texturehelper.cpp b/src/datavis3d/utils/texturehelper.cpp
index 4007953f..808ac309 100644
--- a/src/datavis3d/utils/texturehelper.cpp
+++ b/src/datavis3d/utils/texturehelper.cpp
@@ -195,23 +195,25 @@ GLuint TextureHelper::createDepthTexture(const QSize &size, GLuint &frameBuffer)
 {
     GLuint depthtextureid;
 
-    // Create frame buffer
-    glGenFramebuffers(1, &frameBuffer);
-    glBindFramebuffer(GL_FRAMEBUFFER, frameBuffer);
-
     // Create depth texture for the shadow mapping
     glGenTextures(1, &depthtextureid);
     glBindTexture(GL_TEXTURE_2D, depthtextureid);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
-    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    //glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    //glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_FUNC, GL_LEQUAL);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE, GL_COMPARE_R_TO_TEXTURE);
-    glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT16, size.width(), size.height(), 0,
-                 GL_DEPTH_COMPONENT, GL_FLOAT, NULL);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, size.width(), size.height(), 0,
+                 GL_DEPTH_COMPONENT, GL_UNSIGNED_BYTE, NULL);
     glBindTexture(GL_TEXTURE_2D, 0);
 
+    // Create frame buffer
+    glGenFramebuffers(1, &frameBuffer);
+    glBindFramebuffer(GL_FRAMEBUFFER, frameBuffer);
+
     // Attach texture to depth attachment
     glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depthtextureid, 0);