From cbad0a7684e07a62159a6a550e9546c8b6a6720e Mon Sep 17 00:00:00 2001
From: Paul McCarthy <pauld.mccarthy@gmail.com>
Date: Fri, 22 Jan 2016 11:37:18 +0000
Subject: [PATCH] GLSLShader.set keeps track of value changes, and returns True
or False so caller can tell whether shader state was actually changed.
GLVolume (for OpenGL 2.1) updated to use this feature.
---
fsl/fsleyes/gl/gl14/glvolume_funcs.py | 2 ++
fsl/fsleyes/gl/gl21/glvolume_funcs.py | 32 +++++++++++++++-----------
fsl/fsleyes/gl/glvolume.py | 5 ++--
fsl/fsleyes/gl/shaders/glsl/program.py | 20 +++++++++++++++-
4 files changed, 41 insertions(+), 18 deletions(-)
diff --git a/fsl/fsleyes/gl/gl14/glvolume_funcs.py b/fsl/fsleyes/gl/gl14/glvolume_funcs.py
index 3b1852abe..8fe4900c9 100644
--- a/fsl/fsleyes/gl/gl14/glvolume_funcs.py
+++ b/fsl/fsleyes/gl/gl14/glvolume_funcs.py
@@ -106,6 +106,8 @@ def updateShaderState(self):
self.shader.unload()
+ return True
+
def preDraw(self):
"""Prepares to draw a slice from the given :class:`.GLVolume` instance. """
diff --git a/fsl/fsleyes/gl/gl21/glvolume_funcs.py b/fsl/fsleyes/gl/gl21/glvolume_funcs.py
index 9fabd0001..0d437e29d 100644
--- a/fsl/fsleyes/gl/gl21/glvolume_funcs.py
+++ b/fsl/fsleyes/gl/gl21/glvolume_funcs.py
@@ -83,24 +83,28 @@ def updateShaderState(self):
self.colourTexture.getCoordinateTransform())
shader.load()
+
+ changed = False
- shader.set('useSpline', opts.interpolation == 'spline')
- shader.set('imageShape', self.image.shape[:3])
- shader.set('clipLow', clipLow)
- shader.set('clipHigh', clipHigh)
- shader.set('texZero', texZero)
- shader.set('invertClip', opts.invertClipping)
- shader.set('useNegCmap', opts.useNegativeCmap)
- shader.set('imageIsClip', opts.clipImage is None)
- shader.set('img2CmapXform', img2CmapXform)
-
- shader.set('imageTexture', 0)
- shader.set('colourTexture', 1)
- shader.set('negColourTexture', 2)
- shader.set('clipTexture', 3)
+ changed |= shader.set('useSpline', opts.interpolation == 'spline')
+ changed |= shader.set('imageShape', self.image.shape[:3])
+ changed |= shader.set('clipLow', clipLow)
+ changed |= shader.set('clipHigh', clipHigh)
+ changed |= shader.set('texZero', texZero)
+ changed |= shader.set('invertClip', opts.invertClipping)
+ changed |= shader.set('useNegCmap', opts.useNegativeCmap)
+ changed |= shader.set('imageIsClip', opts.clipImage is None)
+ changed |= shader.set('img2CmapXform', img2CmapXform)
+
+ changed |= shader.set('imageTexture', 0)
+ changed |= shader.set('colourTexture', 1)
+ changed |= shader.set('negColourTexture', 2)
+ changed |= shader.set('clipTexture', 3)
shader.unload()
+ return changed
+
def preDraw(self):
"""Sets up the GL state to draw a slice from the given :class:`.GLVolume`
diff --git a/fsl/fsleyes/gl/glvolume.py b/fsl/fsleyes/gl/glvolume.py
index 5e07775dc..261488e83 100644
--- a/fsl/fsleyes/gl/glvolume.py
+++ b/fsl/fsleyes/gl/glvolume.py
@@ -265,11 +265,10 @@ class GLVolume(globject.GLImageObject):
def update(*a):
self.notify()
-
def shaderUpdate(*a):
if self.ready():
- fslgl.glvolume_funcs.updateShaderState(self)
- self.notify()
+ if fslgl.glvolume_funcs.updateShaderState(self):
+ self.notify()
def colourUpdate(*a):
self.refreshColourTextures()
diff --git a/fsl/fsleyes/gl/shaders/glsl/program.py b/fsl/fsleyes/gl/shaders/glsl/program.py
index 49275d54e..9e3c381c7 100644
--- a/fsl/fsleyes/gl/shaders/glsl/program.py
+++ b/fsl/fsleyes/gl/shaders/glsl/program.py
@@ -149,6 +149,13 @@ class GLSLShader(object):
self.vertUniforms,
self.fragUniforms)
+ # We cache the most recent value for
+ # every uniform. When a call to set()
+ # is made, if the value is unchanged,
+ # we skip the GL call.
+ self.values = {n : None for n in self.positions.keys()}
+
+ # Buffers for vertex attributes
self.buffers = {}
for att in self.vertAttributes:
@@ -234,7 +241,16 @@ class GLSLShader(object):
def set(self, name, value):
- """Sets the value for the specified GLSL ``uniform`` variable. """
+ """Sets the value for the specified GLSL ``uniform`` variable.
+
+ The ``GLSLShader`` keeps a copy of the value of every uniform, to
+ avoid unnecessary GL calls.
+
+ :returns: ``True`` if the value was changed, ``False`` otherwise.
+ """
+
+ if self.values[name] == value:
+ return False
vPos = self.positions[name]
vType = self.types[ name]
@@ -250,6 +266,8 @@ class GLSLShader(object):
setfunc(vPos, value)
+ return True
+
def setAtt(self, name, value, divisor=None):
"""Sets the value for the specified GLSL ``attribute`` variable.
--
GitLab