[1.8] Drawing enchantment glint over a regular quad

[TheNuclearDuck]

I've been able to draw the enchantment effect over a quad in 1.7.10, using the following method:

/** Bits which are modified while rendering item glints, so must be pushed/popped.
     * @see #drawTexturedGlintRect(int, int, int, int, int, int) */
    public static final int GL_GLINT_BITS =
            GL_ENABLE_BIT | GL_TEXTURE_BIT | GL_TRANSFORM_BIT |
            GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT | GL_CURRENT_BIT;

    /** Render an 'item glint' over the specified quad with the currently bound texture for clipping.
     * @param x X coordinate of the top-left
     * @param y Y coordinate of the top-left
     * @param u Texture X coordinate, in pixels
     * @param v Texture Y coordinate, in pixels
     * @param width The width of the quad to draw, in pixels
     * @param height The height of the quad to draw, in pixels
     * @see ItemRenderer#renderItem(net.minecraft.entity.EntityLivingBase, ItemStack, int, net.minecraftforge.client.IItemRenderer.ItemRenderType) */
    public void drawTexturedGlintRect(int x, int y, int u, int v, int width, int height) {
        mc.mcProfiler.startSection("glint");
        // Push bits we modify to restore later on
        glPushAttrib(GL_GLINT_BITS);

        glDepthFunc(GL_EQUAL);
        glDisable(GL_LIGHTING);
        glEnable(GL_BLEND);
        // Mapped OpenGL constants from [768, 1, 1, 0]
        OpenGlHelper.glBlendFunc(GL_SRC_COLOR, GL_ONE, GL_ONE, GL_ZERO);

        glColor4f(0.38F, 0.19F, 0.608F, 1.0F); // #61309B, light purple tint
        mc.getTextureManager().bindTexture(RES_ITEM_GLINT);

        glMatrixMode(GL_TEXTURE);

        long time = Minecraft.getSystemTime();

        // Rect #1
        glPushMatrix();
        glScalef(0.125F, 0.125F, 0.125F);
        glTranslatef((float) (time % 3000L) / 3000.0F * 8.0F, 0.0F, 0.0F);
        glRotatef(-50.0F, 0.0F, 0.0F, 1.0F);
        this.drawTexturedModalRect(x, y, u, v, width, height);
        glPopMatrix();

        // Rect #2
        glPushMatrix();
        glScalef(0.125F, 0.125F, 0.125F);
        glTranslatef((float) (time % 4873L) / 4873.0F * -8.0F, 0.0F, 0.0F);
        glRotatef(10.0F, 0.0F, 0.0F, 1.0F);
        this.drawTexturedModalRect(x, y, u, v, width, height);
        glPopMatrix();

        glPopAttrib();
        mc.mcProfiler.endSection();
    }

 

This works perfectly, if I run it after drawTexturedModalRect. It was ripped and slightly modified from vanilla's method for rendering over items, but since item rendering has changed a lot between 1.7.10 and 1.8 it no longer works. The new method of rendering items seems to be so complicated that I can't find any new method of doing this.

 

In 1.8, this code sort of works correctly, for the first quad I draw it over. Any further quads cause the texture to remain blank for most of the time, then very quickly the entire enchantment texture moves across the quad and disappears again for a second or two. Any ideas on how this same effect can be achieved in 1.8?

[RANKSHANK]

In 1.8, this code sort of works correctly, for the first quad I draw it over. Any further quads cause the texture to remain blank for most of the time, then very quickly the entire enchantment texture moves across the quad and disappears again for a second or two. Any ideas on how this same effect can be achieved in 1.8?

Not directly a solution, but the error on the additional quads sounds like an undersized UV area. I've messed around previously with the Glint for a shield esque overlay and when its UV coords aren't displaced enough you get gaps akin to what you've described because it 'zooms' in on the textures.

[TheNuclearDuck]

In 1.8, this code sort of works correctly, for the first quad I draw it over. Any further quads cause the texture to remain blank for most of the time, then very quickly the entire enchantment texture moves across the quad and disappears again for a second or two. Any ideas on how this same effect can be achieved in 1.8?

Not directly a solution, but the error on the additional quads sounds like an undersized UV area. I've messed around previously with the Glint for a shield esque overlay and when its UV coords aren't displaced enough you get gaps akin to what you've described because it 'zooms' in on the textures.

Why would the UVs have changed at all between me rendering these two quads (the only thing inbetween is a regular quad, drawTexturedModalRect). I wouldn't thought it was some OpenGL state that's now changed in 1.8... Hmm. I wish I could say I had any ideas.

[RANKSHANK]

I couldn't tell you with certainty, but if you're seeing the artifacts of the texture then it's likely a uv scaling/ timing issue... do you mind showing where/how you're invoking this?

[TheNuclearDuck]

I couldn't tell you with certainty, but if you're seeing the artifacts of the texture then it's likely a uv scaling/ timing issue... do you mind showing where/how you're invoking this?

GitHub. This is for 1.7.10, but none of the code has changed apart from things like replacing .addVertexWithUV from Tessellator to WorldRenderer.

[RANKSHANK]

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Got this from snagging RenderItem.renderEffect(IBakedModel) and replacing model rendering with

Minecraft.getMinecraft().ingameGUI.drawTexturedModalRect(0,0,0,0,scaledWidth, scaledHeight);

and it worked fine as far as speed and such goes.... So comparing against this and looking at your code I *think* I see the culprit:

 

this.drawTexturedGlintRect(left + this.left, this.top, (int) uv.x, (int) uv.y, 5, 9);

your UV is set to a specific slot... try forcing it to use the full Glint texture instead of a portion of it.

[TheNuclearDuck]

FIXED! The solution wasn't exactly what you said, but your findings did cause me to look into a few things. First, I rendered the whole texture so I could see better, then I looked into RenderItem#renderEffect(). I found that some of my calculations were weirdly flipped (*8 instead of /8, for example). I think this was actually part of a previous attempt to fix the problem, someone suggested using the reciprocal. Either way, that caused the animation to work properly again (did have to mess around with the bound texture, though...)

 

Thank you RANKSHANK!