/**
* Draws a frame where the electron beam has been stretched out into a thin white horizontal line
* that fades as it collapses inwards.
*
* @param stretch The stretch factor. 0.0 is maximum stretch / no fade, 1.0 is collapsed / maximum
* fade.
*/
private void drawHStretch(float stretch) {
// compute interpolation scale factor
final float ag = scurve(stretch, 8.0f);
if (DEBUG) {
Slog.d(TAG, "drawHStretch: stretch=" + stretch + ", ag=" + ag);
}
if (stretch < 1.0f) {
// bind vertex buffer
GLES10.glVertexPointer(2, GLES10.GL_FLOAT, 0, mVertexBuffer);
GLES10.glEnableClientState(GLES10.GL_VERTEX_ARRAY);
// draw narrow fading white line
setHStretchQuad(mVertexBuffer, mDisplayWidth, mDisplayHeight, ag, mSwapNeeded);
GLES10.glColor4f(1.0f - ag * 0.75f, 1.0f - ag * 0.75f, 1.0f - ag * 0.75f, 1.0f);
GLES10.glDrawArrays(GLES10.GL_TRIANGLE_FAN, 0, 4);
// clean up
GLES10.glDisableClientState(GLES10.GL_VERTEX_ARRAY);
}
}
/**
* Draws a frame where the content of the electron beam is collapsing inwards upon itself
* vertically with red / green / blue channels dispersing and eventually merging down to a single
* horizontal line.
*
* @param stretch The stretch factor. 0.0 is no collapse, 1.0 is full collapse.
*/
private void drawVStretch(float stretch) {
// compute interpolation scale factors for each color channel
final float ar = scurve(stretch, 7.5f);
final float ag = scurve(stretch, 8.0f);
final float ab = scurve(stretch, 8.5f);
if (DEBUG) {
Slog.d(TAG, "drawVStretch: stretch=" + stretch + ", ar=" + ar + ", ag=" + ag + ", ab=" + ab);
}
// set blending
GLES10.glBlendFunc(GLES10.GL_ONE, GLES10.GL_ONE);
GLES10.glEnable(GLES10.GL_BLEND);
// bind vertex buffer
GLES10.glVertexPointer(2, GLES10.GL_FLOAT, 0, mVertexBuffer);
GLES10.glEnableClientState(GLES10.GL_VERTEX_ARRAY);
// set-up texturing
GLES10.glDisable(GLES10.GL_TEXTURE_2D);
GLES10.glEnable(GLES11Ext.GL_TEXTURE_EXTERNAL_OES);
// bind texture and set blending for drawing planes
GLES10.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, mTexNames[0]);
GLES10.glTexEnvx(
GLES10.GL_TEXTURE_ENV,
GLES10.GL_TEXTURE_ENV_MODE,
mMode == MODE_WARM_UP ? GLES10.GL_MODULATE : GLES10.GL_REPLACE);
GLES10.glTexParameterx(
GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES10.GL_TEXTURE_MAG_FILTER, GLES10.GL_LINEAR);
GLES10.glTexParameterx(
GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES10.GL_TEXTURE_MIN_FILTER, GLES10.GL_LINEAR);
GLES10.glTexParameterx(
GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES10.GL_TEXTURE_WRAP_S, GLES10.GL_CLAMP_TO_EDGE);
GLES10.glTexParameterx(
GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES10.GL_TEXTURE_WRAP_T, GLES10.GL_CLAMP_TO_EDGE);
GLES10.glEnable(GLES11Ext.GL_TEXTURE_EXTERNAL_OES);
GLES10.glTexCoordPointer(2, GLES10.GL_FLOAT, 0, mTexCoordBuffer);
GLES10.glEnableClientState(GLES10.GL_TEXTURE_COORD_ARRAY);
// draw the red plane
setVStretchQuad(mVertexBuffer, mDisplayWidth, mDisplayHeight, ar, mSwapNeeded);
GLES10.glColorMask(true, false, false, true);
GLES10.glDrawArrays(GLES10.GL_TRIANGLE_FAN, 0, 4);
// draw the green plane
setVStretchQuad(mVertexBuffer, mDisplayWidth, mDisplayHeight, ag, mSwapNeeded);
GLES10.glColorMask(false, true, false, true);
GLES10.glDrawArrays(GLES10.GL_TRIANGLE_FAN, 0, 4);
// draw the blue plane
setVStretchQuad(mVertexBuffer, mDisplayWidth, mDisplayHeight, ab, mSwapNeeded);
GLES10.glColorMask(false, false, true, true);
GLES10.glDrawArrays(GLES10.GL_TRIANGLE_FAN, 0, 4);
// clean up after drawing planes
GLES10.glDisable(GLES11Ext.GL_TEXTURE_EXTERNAL_OES);
GLES10.glDisableClientState(GLES10.GL_TEXTURE_COORD_ARRAY);
GLES10.glColorMask(true, true, true, true);
// draw the white highlight (we use the last vertices)
if (mMode == MODE_COOL_DOWN) {
GLES10.glColor4f(ag, ag, ag, 1.0f);
GLES10.glDrawArrays(GLES10.GL_TRIANGLE_FAN, 0, 4);
}
// clean up
GLES10.glDisableClientState(GLES10.GL_VERTEX_ARRAY);
GLES10.glDisable(GLES10.GL_BLEND);
}