/**
* Creates a 2D texture of the given format and dimensions and returns the
* texture object identifier. This method is typically used to create a
* temporary texture for intermediate work, such as in the
* OGLContext_InitBlitTileTexture() method below.
*/
GLuint
OGLContext_CreateBlitTexture(GLenum internalFormat, GLenum pixelFormat,
GLuint width, GLuint height)
{
GLuint texID;
GLint sp, sr, rl, align;
GLclampf priority = 1.0f;
J2dTraceLn(J2D_TRACE_INFO, "OGLContext_CreateBlitTexture");
j2d_glGenTextures(1, &texID);
j2d_glBindTexture(GL_TEXTURE_2D, texID);
j2d_glPrioritizeTextures(1, &texID, &priority);
j2d_glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
j2d_glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
OGLSD_RESET_TEXTURE_WRAP(GL_TEXTURE_2D);
// save pixel store parameters (since this method could be invoked after
// the caller has already set up its pixel store parameters)
j2d_glGetIntegerv(GL_UNPACK_SKIP_PIXELS, &sp);
j2d_glGetIntegerv(GL_UNPACK_SKIP_ROWS, &sr);
j2d_glGetIntegerv(GL_UNPACK_ROW_LENGTH, &rl);
j2d_glGetIntegerv(GL_UNPACK_ALIGNMENT, &align);
// set pixel store parameters to default values
j2d_glPixelStorei(GL_UNPACK_SKIP_PIXELS, 0);
j2d_glPixelStorei(GL_UNPACK_SKIP_ROWS, 0);
j2d_glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
j2d_glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
j2d_glTexImage2D(GL_TEXTURE_2D, 0, internalFormat,
width, height, 0,
pixelFormat, GL_UNSIGNED_BYTE, NULL);
// restore pixel store parameters
j2d_glPixelStorei(GL_UNPACK_SKIP_PIXELS, sp);
j2d_glPixelStorei(GL_UNPACK_SKIP_ROWS, sr);
j2d_glPixelStorei(GL_UNPACK_ROW_LENGTH, rl);
j2d_glPixelStorei(GL_UNPACK_ALIGNMENT, align);
return texID;
}
/**
* Returns JNI_TRUE only if all of the following conditions are met:
* - the GL_ARB_fragment_shader extension is available
* - the LCD text shader codepath has been enabled via the system property
* - the hardware supports the minimum number of texture units
*/
static jboolean
OGLContext_IsLCDShaderSupportAvailable(JNIEnv *env,
jboolean fragShaderAvailable)
{
jboolean isLCDShaderEnabled = JNI_FALSE;
GLint maxTexUnits;
J2dTraceLn(J2D_TRACE_INFO, "OGLContext_IsLCDShaderSupportAvailable");
// first see if the fragment shader extension is available
if (!fragShaderAvailable) {
return JNI_FALSE;
}
// next see if the lcdshader system property has been enabled
isLCDShaderEnabled =
JNU_GetStaticFieldByName(env, NULL,
"sun/java2d/opengl/OGLSurfaceData",
"isLCDShaderEnabled", "Z").z;
if (!isLCDShaderEnabled) {
J2dRlsTraceLn(J2D_TRACE_INFO,
"OGLContext_IsLCDShaderSupportAvailable: disabled via flag");
return JNI_FALSE;
}
// finally, check to see if the hardware supports the required number
// of texture units
j2d_glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS_ARB, &maxTexUnits);
if (maxTexUnits < 2) {
J2dRlsTraceLn1(J2D_TRACE_INFO,
"OGLContext_IsLCDShaderSupportAvailable: not enough tex units (%d)",
maxTexUnits);
}
J2dRlsTraceLn(J2D_TRACE_INFO,
"OGLContext_IsLCDShaderSupportAvailable: LCD text shader supported");
return JNI_TRUE;
}
/**
* Initializes an OpenGL texture object.
*
* If the isOpaque parameter is JNI_FALSE, then the texture will have a
* full alpha channel; otherwise, the texture will be opaque (this can
* help save VRAM when translucency is not needed).
*
* If the GL_ARB_texture_non_power_of_two extension is present (texNonPow2
* is JNI_TRUE), the actual texture is allowed to have non-power-of-two
* dimensions, and therefore width==textureWidth and height==textureHeight.
*
* Failing that, if the GL_ARB_texture_rectangle extension is present
* (texRect is JNI_TRUE), the actual texture is allowed to have
* non-power-of-two dimensions, except that instead of using the usual
* GL_TEXTURE_2D target, we need to use the GL_TEXTURE_RECTANGLE_ARB target.
* Note that the GL_REPEAT wrapping mode is not allowed with this target,
* so if that mode is needed (e.g. as is the case in the TexturePaint code)
* one should pass JNI_FALSE to avoid using this extension. Also note that
* when the texture target is GL_TEXTURE_RECTANGLE_ARB, texture coordinates
* must be specified in the range [0,width] and [0,height] rather than
* [0,1] as is the case with the usual GL_TEXTURE_2D target (so take care)!
*
* Otherwise, the actual texture must have power-of-two dimensions, and
* therefore the textureWidth and textureHeight will be the next
* power-of-two greater than (or equal to) the requested width and height.
*/
static jboolean
OGLSD_InitTextureObject(OGLSDOps *oglsdo,
jboolean isOpaque,
jboolean texNonPow2, jboolean texRect,
jint width, jint height)
{
GLenum texTarget, texProxyTarget;
GLint format = isOpaque ? GL_RGB : GL_RGBA;
GLuint texID;
GLsizei texWidth, texHeight, realWidth, realHeight;
GLint texMax;
J2dTraceLn4(J2D_TRACE_INFO,
"OGLSD_InitTextureObject: w=%d h=%d opq=%d nonpow2=%d",
width, height, isOpaque, texNonPow2);
if (oglsdo == NULL) {
J2dRlsTraceLn(J2D_TRACE_ERROR,
"OGLSD_InitTextureObject: ops are null");
return JNI_FALSE;
}
if (texNonPow2) {
// use non-pow2 dimensions with GL_TEXTURE_2D target
j2d_glGetIntegerv(GL_MAX_TEXTURE_SIZE, &texMax);
texWidth = (width <= texMax) ? width : 0;
texHeight = (height <= texMax) ? height : 0;
texTarget = GL_TEXTURE_2D;
texProxyTarget = GL_PROXY_TEXTURE_2D;
} else if (texRect) {
// use non-pow2 dimensions with GL_TEXTURE_RECTANGLE_ARB target
j2d_glGetIntegerv(GL_MAX_RECTANGLE_TEXTURE_SIZE_ARB, &texMax);
texWidth = (width <= texMax) ? width : 0;
texHeight = (height <= texMax) ? height : 0;
texTarget = GL_TEXTURE_RECTANGLE_ARB;
texProxyTarget = GL_PROXY_TEXTURE_RECTANGLE_ARB;
} else {
// find the appropriate power-of-two dimensions
j2d_glGetIntegerv(GL_MAX_TEXTURE_SIZE, &texMax);
texWidth = OGLSD_NextPowerOfTwo(width, texMax);
texHeight = OGLSD_NextPowerOfTwo(height, texMax);
texTarget = GL_TEXTURE_2D;
texProxyTarget = GL_PROXY_TEXTURE_2D;
}
J2dTraceLn3(J2D_TRACE_VERBOSE,
" desired texture dimensions: w=%d h=%d max=%d",
texWidth, texHeight, texMax);
// if either dimension is 0, we cannot allocate a texture with the
// requested dimensions
if ((texWidth == 0) || (texHeight == 0)) {
J2dRlsTraceLn(J2D_TRACE_ERROR,
"OGLSD_InitTextureObject: texture dimensions too large");
return JNI_FALSE;
}
// now use a proxy to determine whether we can create a texture with
// the calculated power-of-two dimensions and the given internal format
j2d_glTexImage2D(texProxyTarget, 0, format,
texWidth, texHeight, 0,
format, GL_UNSIGNED_BYTE, NULL);
j2d_glGetTexLevelParameteriv(texProxyTarget, 0,
GL_TEXTURE_WIDTH, &realWidth);
j2d_glGetTexLevelParameteriv(texProxyTarget, 0,
GL_TEXTURE_HEIGHT, &realHeight);
// if the requested dimensions and proxy dimensions don't match,
// we shouldn't attempt to create the texture
if ((realWidth != texWidth) || (realHeight != texHeight)) {
J2dRlsTraceLn2(J2D_TRACE_ERROR,
"OGLSD_InitTextureObject: actual (w=%d h=%d) != requested",
realWidth, realHeight);
return JNI_FALSE;
}
// initialize the texture with some dummy data (this allows us to create
// a texture object once with 2^n dimensions, and then use
// glTexSubImage2D() to provide further updates)
j2d_glGenTextures(1, &texID);
j2d_glBindTexture(texTarget, texID);
j2d_glTexImage2D(texTarget, 0, format,
texWidth, texHeight, 0,
format, GL_UNSIGNED_BYTE, NULL);
oglsdo->isOpaque = isOpaque;
oglsdo->xOffset = 0;
oglsdo->yOffset = 0;
oglsdo->width = width;
oglsdo->height = height;
oglsdo->textureID = texID;
oglsdo->textureWidth = texWidth;
oglsdo->textureHeight = texHeight;
oglsdo->textureTarget = texTarget;
OGLSD_INIT_TEXTURE_FILTER(oglsdo, GL_NEAREST);
OGLSD_RESET_TEXTURE_WRAP(texTarget);
J2dTraceLn3(J2D_TRACE_VERBOSE, " created texture: w=%d h=%d id=%d",
width, height, texID);
return JNI_TRUE;
}
