SptFromCode()

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Syntax

SptFromCode(dwBmpAlias As dwTftLibParameter1, bBuffer As bTftLibParameter1, bTransparent As bTftLibParameter2, wAlphaColor As wTftLibParameter1, bOverlay As bTftLibParameter3), Byte

Overview

Load a BMP image stored in flash program memory into a sprite buffer for further processing or for later rendering to the TFT screen.

- If transparent mode is enabled, any pixels matching the specified Alpha Color are omitted, thereby preserving the existing pixels already present in the sprite buffer.

- If an overlay function is selected, it is applied in accordance with the transparency rule.

Parameters

Parameter

Description

dwBmpAlias

Name of the BMP image table stored in flash memory

bBuffer

Sprite buffer index where the image data will be loaded

bTransparent

0 = Normal load (no transparency)

1 = Transparent load (pixels matching the alpha color are skipped)

wAlphaColor — Alpha color value used when transparent loading is enabled

bOverlay — Pixel overlay effect to apply during the load operation:

0 = NONE – No overlay; direct pixel replacement

1 = OR – Lightens overlapping areas (adds bits); merges bright regions

2 = AND – Keeps only common bits; intersection-style effect

3 = XOR – Highlights differences; toggles pixels where colors differ

4 = NAND – Inverts the intersection; brightens overlap zones

5 = NOR – Inverts the union; creates darker overlays

6 = XNOR – Keeps pixels unchanged where both match; strong masking effect

7 = ADD – Adds color values; brightens overlapping regions (light addition)

8 = SUB – Subtracts color values; darkens overlaps (shadow-like effect)

9 = AVG – Averages colors; produces a soft blending effect

10 = SCR – Screen blend (inverse multiply); brightens highlights

11 = MUL – Multiply blend; darkens overlapping areas (similar to Photoshop “Multiply”)

12 = CON – Contrast blend; enhances midtones with a non-linear mix

Return value

Value

Meaning

0

Operation completed successfully

1

Invalid buffer index

2

Buffer is not fully within the allowed RAM space

3

Buffer size is smaller than the image area to be copied

Created with the Personal Edition of HelpNDoc: Easily convert your WinHelp HLP help files to CHM with HelpNDoc's step-by-step guide